tag:theconversation.com,2011:/us/topics/neurological-disease-63948/articlesNeurological disease – The Conversation2024-02-07T17:30:26Ztag:theconversation.com,2011:article/2224582024-02-07T17:30:26Z2024-02-07T17:30:26ZThe brain is the most complicated object in the universe. This is the story of scientists’ quest to decode it – and read people’s minds<figure><img src="https://images.theconversation.com/files/573721/original/file-20240206-26-8guoy5.jpg?ixlib=rb-1.1.0&rect=299%2C119%2C3586%2C2874&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">HuthLab researchers (l-r) Alex Huth, Shailee Jain and Jerry Tang behind an fMRI scanner in the University of Texas's Biomedical Imaging Center.</span> <span class="attribution"><a class="source" href="https://cns.utexas.edu/news/podcast/brain-activity-decoder-can-reveal-stories-peoples-minds">Nolan Zunk/UT Austin</a></span></figcaption></figure><p>In the middle of 2023, a <a href="https://news.utexas.edu/2023/05/01/brain-activity-decoder-can-reveal-stories-in-peoples-minds/">study</a> conducted by the HuthLab at the University of Texas sent shockwaves through the realms of neuroscience and technology. For the first time, the thoughts and impressions of people unable to communicate with the outside world were translated into continuous natural language, using a combination of artificial intelligence (AI) and brain imaging technology.</p>
<p>This is the closest science has yet come to reading someone’s mind. While advances in neuroimaging over the past two decades have enabled non-responsive and minimally conscious patients to control a computer cursor with their brain, HuthLab’s research is a significant step closer towards accessing people’s actual thoughts. As Alexander Huth, the neuroscientist who co-led the research, <a href="https://www.nytimes.com/2023/05/01/science/ai-speech-language.html">told the New York Times</a>:</p>
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<p>This isn’t just a language stimulus. We’re getting at meaning – something about the idea of what’s happening. And the fact that’s possible is very exciting.</p>
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<p>Combining AI and brain-scanning technology, the team created a non-invasive brain decoder capable of <a href="https://www.biorxiv.org/content/10.1101/2022.09.29.509744v1">reconstructing continuous natural language</a> among people otherwise unable to communicate with the outside world. The development of such technology – and the parallel development of <a href="https://iopscience.iop.org/article/10.1088/2516-1091/ac23e6/meta">brain-controlled motor prosthetics</a> that enable paralysed patients to achieve some renewed mobility – holds tremendous prospects for people suffering from neurological diseases including <a href="https://www.ninds.nih.gov/health-information/disorders/locked-syndrome#:%7E:text=Locked%2Din%20syndrome%20is%20a,communicate%20with%20blinking%20eye%20movements">locked-in syndrome</a> and <a href="https://www.britannica.com/science/quadriplegia">quadriplegia</a>.</p>
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<figcaption><span class="caption">Report on HuthLab’s ‘mind reading’ research by CBS Austin.</span></figcaption>
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<p>In the longer term, this could lead to wider public applications such as fitbit-style <a href="https://insider.fitt.co/a-50k-fitbit-for-your-brain/">health monitors for the brain</a> and <a href="https://link.springer.com/chapter/10.1007/978-3-319-94544-6_4">brain-controlled smartphones</a>. On January 29, Elon Musk <a href="https://twitter.com/elonmusk/status/1752098683024220632">announced</a> that his Neuralink tech startup had implanted a chip in a human brain for the first time. He had previously told followers that Neuralink’s first product, <a href="https://twitter.com/elonmusk/status/1752118131579867417">Telepathy</a>, would one day allow people to control their phones or computers “just by thinking”.</p>
<p>But alongside such technological developments come major <a href="https://theconversation.com/mri-scans-and-ai-technology-really-could-read-what-were-thinking-the-implications-are-terrifying-205503">ethical and legal concerns</a>. It’s not only privacy but the <a href="https://theconversation.com/freedom-of-thought-is-being-threatened-by-states-big-tech-and-even-ourselves-heres-what-we-can-do-to-protect-it-220266">very identity of people</a> that may be at risk. As we enter this new era of so-called <a href="https://www.newscientist.com/article/2408019-mind-reading-ai-can-translate-brainwaves-into-written-text/#:%7E:text=Using%20only%20a%20sensor%2Dfilled,person's%20thoughts%20into%20written%20words.">mind-reading technology</a>, we will also need to consider how to prevent its potential to help people being outweighed by its potential to do harm.</p>
<h2>Humanity’s greatest mapping challenge</h2>
<p>The brain is the <a href="https://today.uconn.edu/2018/03/complicated-object-universe/">most complicated object in the universe</a>. It contains more than 89 billion neurons, each connected to around 7,000 other neurons that send between ten and 100 signals every second. The development of AI was based on the brain and the <a href="https://theconversation.com/ai-will-soon-become-impossible-for-humans-to-comprehend-the-story-of-neural-networks-tells-us-why-199456">concept of neurons working together</a>. Now, the way AI works with deep learning is helping us understand much more clearly how the brain works.</p>
<p>By fully mapping the structure and function of a healthy human brain, we can determine with great precision what goes awry in diseases of the brain and mind. In 2009, <a href="https://humanconnectome.org/">the Human Connectome Project</a> was launched by the US National Institute of Health with the goal of building a map of the structure and function of a healthy human brain. Similar initiatives were launched in Europe in 2013 (<a href="http://www.humanbrainproject.eu/">the Human Brain Project</a>) and China in 2016 (<a href="https://www.sciencedirect.com/science/article/pii/S0896627316308005?via%3Dihub">the China Brain Project</a>).</p>
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<figcaption><span class="caption">Human Connectome video by BrainFacts.org.</span></figcaption>
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<p>This daunting endeavour may still take generations to complete – but the scientific ambition of mapping and reading people’s brains dates back more than two centuries. With the world having been circumnavigated many times over, Antarctica discovered and much of the planet charted, humanity was ready for a new (and even more complicated) mapping challenge – the human brain.</p>
<p>These efforts began in earnest in the late 18th century with the development of a systematic framework for scientists to ask how the brain and its regions produce psychological experiences – our thoughts, feelings and behaviour. One of the earliest attempts was <a href="https://www.britannica.com/topic/phrenology">phrenology</a>, pioneered by the Austrian physician and anatomist Franz Joseph Gall.</p>
<p>While this long-discredited science may now be best known for the <a href="https://artsci.case.edu/dittrick/online-exhibits/explore-the-artifacts/phrenology-bust-1850/">decorative busts</a> sold in flea markets, it was all the rage by the early 19th century. Gall and his assistant Johann Spurzheim suggested that the brain was organised along 35 psychological functions, each linked to a different underlying region.</p>
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<p><em>Across the world, we’re seeing unprecedented levels of mental illness at all ages, from children to the very old – with huge costs to families, communities and economies. <a href="https://theconversation.com/uk/topics/tackling-the-mental-health-crisis-147216?utm_source=TCUK&utm_medium=ArticleTop&utm_campaign=MentalHealthSeries">In this series</a>, we investigate what’s causing this crisis, and report on the latest research to improve people’s mental health at all stages of life.</em></p>
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<p>Just as you might start lifting dumbbells if you want larger biceps, phrenology argued that the more you use a particular psychological function, the more the brain region underlying it should grow – leading to a corresponding lump in your skull. <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1445-2197.2005.03426.x">According to Gall and Spurzheim</a>, some of these functions (including memory, love of offspring and the instinct to kill) were shared with animals, whereas others (such as wit, poetic ability and morality) were uniquely human.</p>
<p>Throughout the British empire and later in the US, phrenology was used to justify classism, colonialism, slavery and white supremacy. Queen Victoria had readings done on her children, but Napoleon Bonaparte was not a fan. When Gall moved to Paris in 1807 to perform much of his phrenological theorising, France’s emperor pronounced: “It is an ingenious fable which might seduce the <em>gens du monde</em>, but could not stand the scrutiny of the anatomist.”</p>
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<a href="https://images.theconversation.com/files/572529/original/file-20240131-15-j86pu0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An old shop window with a large phrenology sign" src="https://images.theconversation.com/files/572529/original/file-20240131-15-j86pu0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572529/original/file-20240131-15-j86pu0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=470&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572529/original/file-20240131-15-j86pu0.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=470&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572529/original/file-20240131-15-j86pu0.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=470&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572529/original/file-20240131-15-j86pu0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=591&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572529/original/file-20240131-15-j86pu0.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=591&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572529/original/file-20240131-15-j86pu0.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=591&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">A phrenology shop in New Orleans in 1936.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Phrenology_Shop_in_New_Orleans_1936_by_Peter_Sekaer.jpg">Peter Sekaer/Wikimedia Commons</a></span>
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<p>In the 1860s, “locationist” views of how the brain worked made a comeback – though the scientists leading this research were keen to distinguish their theories from phrenology. French anatomist Paul Broca discovered a region of the left hemisphere responsible for producing speech – thanks in part to his patient, Louis Victor Leborgne, who at age 30 <a href="https://blogs.scientificamerican.com/literally-psyched/the-man-who-couldnt-speakand-how-he-revolutionized-psychology/">lost the ability to say anything</a> other than the syllable “tan”. Today, <a href="https://link.springer.com/referenceworkentry/10.1007/978-0-387-79948-3_655">Patient Tan</a> remains one of psychology’s most famous case studies, and <a href="https://www.hopkinsmedicine.org/news/media/releases/brocas_area_is_the_brains_scriptwriter_shaping_speech_study_finds">Broca’s area</a>, in the frontal cortex, is one of the most important language regions of the brain, playing a critical part in putting our thoughts into words.</p>
<p>Similarly, German neuroanatomist Korbinian Brodmann’s <a href="https://www.nature.com/articles/461884a#:%7E:text=Korbinian%20Brodmann's%20Localisation%20in%20the,cell%20type%20and%20laminar%20structure.">map of 52 distinct regions of the cerebral cortex</a>, first published in 1909, is still an important tool of contemporary neuroscience – and today’s neuroscientists continue to ask <a href="https://psu.pb.unizin.org/psych425/chapter/locationist-and-one-network-views-of-emotions-in-the-brain/">some of the same questions</a> as these pioneers: are our thoughts, feelings and behaviour produced by the collective action of the brain, or specific brain regions?</p>
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<a href="https://images.theconversation.com/files/572528/original/file-20240131-15-6poatr.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A map of different areas of the brain" src="https://images.theconversation.com/files/572528/original/file-20240131-15-6poatr.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/572528/original/file-20240131-15-6poatr.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=763&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572528/original/file-20240131-15-6poatr.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=763&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572528/original/file-20240131-15-6poatr.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=763&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572528/original/file-20240131-15-6poatr.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=959&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572528/original/file-20240131-15-6poatr.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=959&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572528/original/file-20240131-15-6poatr.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=959&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Brodmann’s brain map.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Brodmann_areas.jpg">Vysha/Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>In modern neuroscience studies, hi-tech scanning tools such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) allow researchers to map the brain by measuring changes in local blood flow that are linked to changes in local neural activity. This approach depends on <a href="https://academic.oup.com/brain/article-abstract/51/3/310/309681?redirectedFrom=fulltext">the findings</a> of American physiologist John Fulton almost a century ago. Fulton was treating Walter K, a 26-year-old sailor suffering from headaches and vision failure. When using his eyes after leaving a dark room, the patient sensed a noise in the back of his head, located over the visual cortex. This stronger pulse of activity was not replicated by other sensory inputs, for example when smelling tobacco or vanilla.</p>
<p>Over the remainder of the 20th century, this first observation of the link between local cerebral blood flow and brain function was built on by neuroscientists including American <a href="https://dm5migu4zj3pb.cloudfront.net/manuscripts/101000/101994/JCI48101994.pdf">Seymour Kety</a> and Swedish collaborators <a href="https://karger.com/ced/article-pdf/11/1/71/2335730/000047614.pdf">David Ingvar</a> and <a href="https://www.jstor.org/stable/24955823">Neils Lassen</a>. Their pioneering work paved the way for modern brain mapping, led by the ground-breaking work of <a href="https://www.braingate.org/about-braingate/">BrainGate</a> – a multidisciplinary research unit originating in the neuroscience department at Brown University in the US state of Rhode Island.</p>
<h2>The first clinical trial</h2>
<p>Prototype brain-computer interfaces (BCIs) record and decode a patient’s brain activity, translating it into actions that can be carried out by a <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8979628/">neural cursor, prosthetic limb or powered exoskeleton</a>. The ultimate goal is wireless, non-invasive devices that help patients communicate and move with precision in the real world. AI is critical to this goal, and is <a href="https://www.cell.com/trends/cognitive-sciences/fulltext/S1364-6613(21)00096-6#secst0015">already being used to help BCI systems</a> produce finely controlled, rapid <a href="https://iopscience.iop.org/article/10.1088/1741-2552/abfaaa/meta">motor movements</a>.</p>
<p>In 2004, <a href="https://www.braingate.org/about-braingate/">BrainGate</a> began the first clinical trial using BCIs to enable patients with impaired motor systems (including spinal cord injuries, <a href="https://pubmed.ncbi.nlm.nih.gov/32809731/#:%7E:text=Brainstem%20infarction%20is%20an%20area,provide%20precise%20diagnosis%20and%20management.">brainstem infarctions</a>, locked-in syndrome and muscular dystrophy) control a computer cursor with their thoughts.</p>
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<img alt="" src="https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/288776/original/file-20190820-170910-8bv1s7.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><strong><em>This article is part of Conversation Insights</em></strong>
<br><em>The Insights team generates <a href="https://theconversation.com/uk/topics/insights-series-71218">long-form journalism</a> derived from interdisciplinary research. The team is working with academics from different backgrounds who have been engaged in projects aimed at tackling societal and scientific challenges.</em></p>
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<p><a href="https://www.patientcareonline.com/view/paralyzed-man-thinks-robotic-devices-motion">Patient MN</a>, a quadriplegic since being stabbed in the neck in 2001, was the trial’s first patient. After neuroscientist Leigh Hochberg’s team implanted electrodes over the hand-arm region of the patient’s primary motor cortex, they <a href="https://www.nature.com/articles/nature04970">reported</a> that Patient MN was able to open emails, draw figures using a paint program, and operate a television using a cursor. In addition, brain activity was linked to the patient’s prosthetic hand and robotic arm, enabling rudimentary actions including grasping and transporting an object. What’s more, these tasks could be done while the patient was having a conversation, suggesting they did not even demand the full concentration of the patient.</p>
<p>Other quadriplegic patients subsequently used BCI devices connected to multi-joint robotic arms to <a href="https://www.nature.com/articles/nature11076">pick up and drink from a cup</a> – and in <a href="https://journals.sagepub.com/doi/10.1177/1545968314554624">2015</a>, a patient with locked-in syndrome was shown operating a point-and-click keyboard five years after the device’s implantation. Advanced decoding algorithms saw their cursor control <a href="https://www.nature.com/articles/nm.3953">improve</a> such that patients went from typing <a href="https://www.science.org/doi/10.1126/scitranslmed.aac7328">24 characters per minute</a> in 2015 to <a href="https://elifesciences.org/articles/18554">39 characters per minute</a> two years later.</p>
<p>Also in 2017, BrainGate clinical trials reported the first evidence that BCIs could be used to <a href="https://www.sciencedirect.com/science/article/abs/pii/S0140673617306013?via%3Dihub">help patients regain movement</a> of their own limbs by bypassing the damaged portion of the spinal cord. One patient with a <a href="https://www.spinalinjury101.org/details/levels-of-injury">high-cervical</a> spinal cord injury was able to reach and grasp a cup eight years after sustaining his injury.</p>
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<figcaption><span class="caption">BrainGate breakthrough video by Brown University.</span></figcaption>
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<p>Then in 2021, the Braingate team reported that quadriplegic patients were now using a <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8218873/">wireless system in their own homes</a> to control a tablet computer – an important first step toward a future where BCI devices can help people move and communicate outside the confines of the hospital or laboratory. Furthermore, the researchers said they anticipate “significant advances and paradigm shifts in neural signal processing, decoding algorithms and control frameworks” in the quest to make such devices available to the wider public.</p>
<p>Beyond Braingate’s successes, another team led by American neurosurgeon Edward Chang <a href="https://www.nature.com/articles/s41586-023-06443-4">recently reported</a> using surgically implanted <a href="https://www.jneurosci.org/content/jneuro/39/22/4299.full.pdf">electrocorticogram</a> electrodes to create a “digital avatar” that could convey what a paralysed patient wants to say. With the help of AI, the BCI decoded muscle movements related to speech the patients were thinking in their minds (as opposed to decoding the actual semantic content).</p>
<p>Activity patterns emerging from the specific brain region that is critical for speech are the key focus for this type of BCI. One expert not involved in the research <a href="https://www.theguardian.com/society/2023/aug/23/paralysed-woman-able-to-speak-through-digital-avatar-for-first-time">told the Guardian</a>: “This is quite a jump from previous results. We’re at a tipping point.”</p>
<h2>A new era of ‘mind reading’ technology</h2>
<p>Brain activity has long been recorded by non-invasive imaging methods such as fMRI and electroencephalography (EEG). But having been primarily envisaged as a tool for diagnostics and monitoring, it is now also a core element of the latest neural communication and prosthetic devices.</p>
<p>A landmark moment came in 2012, when a team led by Canada-based neuroscientist <a href="https://www.youtube.com/watch?v=lvUvY_JrUgA">Adrian Owen</a> used neuroimaging to establish a <a href="https://cris.maastrichtuniversity.nl/ws/portalfiles/portal/75999517/Sorger_2012_Brain_computer_interfaces_for_communcication_with.pdf">line of communication</a> with people suffering from <a href="https://www.nhs.uk/conditions/disorders-of-consciousness/">disorders of consciousness</a>. Despite being behaviourally non-responsive and minimally conscious, these patients were able to answer yes-or-no questions just by using their minds. For patients unable to communicate via facial or eye movements (methods that had been available to locked-in patients for many years), this was a very promising evolution.</p>
<p>Now, a decade on, the <a href="https://www.biorxiv.org/content/10.1101/2022.09.29.509744v1.full">HuthLab research</a> at the University of Texas constitutes a paradigmatic shift in the evolution of communication-enabling neuroimaging systems.</p>
<p>In the study’s first stage, participants were placed in an fMRI scanner and their brain activity was recorded while they listened to 16 hours of podcasts (the model training dataset consisted of 82 five to 15-minute stories taken from the <a href="https://themoth.org/radio-hour">Moth Radio Hour</a> and <a href="https://www.nytimes.com/column/modern-love-podcast">Modern Love)</a>. This brain activity data was then linked to audio fragments the participants were listening to, in order to map what their brain activity patterns looked like when they had specific semantic content in their minds.</p>
<p>Next, the same participants were exposed to new audio fragments they had never heard before, or alternatively were asked to imagine a story. The decoder was then applied to this new set of brain activity data, to “reconstruct” the stories the participants had been listening to or imagining – with some <a href="https://www.biorxiv.org/content/10.1101/2022.09.29.509744v1.full">striking results</a>. For instance, when a patient was played this audio:</p>
<blockquote>
<p>I don’t have my driver’s licence yet and I just jumped out right when I needed to, and she says: ‘Well, why don’t you come back to my house and I’ll give you a ride?’ I say OK.</p>
</blockquote>
<p>… the decoder reconstructed it as follows:</p>
<blockquote>
<p>She is not ready – she has not even started to learn to drive, yet I had to push her out of the car. I said: ‘We will take her home now’ and she agreed.</p>
</blockquote>
<p>While there were also a considerable number of mistakes over the entirety of the trial, the reconstruction of continuous language solely on the base of brain activity patterns, including some exact word matches, is arguably the closest we have yet come to truly reading someone’s thoughts.</p>
<p>Whereas the brain’s capacity to produce motor intentions is shared across species, the ability to produce and perceive language is uniquely human. Thus, decoding actual semantic content from brain activity in regions used in language perception (primarily the <a href="https://www.ncbi.nlm.nih.gov/books/NBK11109/#:%7E:text=The%20association%20cortices%20include%20most,and%20the%20generation%20of%20behavior.">association</a> and <a href="https://www.ncbi.nlm.nih.gov/books/NBK499919/">prefrontal</a> regions of the brain’s cortex) seems more fundamental to what makes us human.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/572526/original/file-20240131-19-2rcmmf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Columns of text comparing actual words with those decoded by the HuthLab brain technology" src="https://images.theconversation.com/files/572526/original/file-20240131-19-2rcmmf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572526/original/file-20240131-19-2rcmmf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=201&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572526/original/file-20240131-19-2rcmmf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=201&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572526/original/file-20240131-19-2rcmmf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=201&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572526/original/file-20240131-19-2rcmmf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=252&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572526/original/file-20240131-19-2rcmmf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=252&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572526/original/file-20240131-19-2rcmmf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=252&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Semantic examples from the HuthLab study.</span>
<span class="attribution"><span class="source">UT Austin</span></span>
</figcaption>
</figure>
<p>Also, the HuthLab study used non-invasive fMRI technology – a form of neuroimaging that measures oxygen levels of blood in the brain in order to make inferences on brain activity. The disadvantage of fMRI is that it can only take slow measurements of brain signals (typically, one brain volume every two or three seconds). The study overcame this by using <a href="https://en.wikipedia.org/wiki/Generative_artificial_intelligence">generative AI</a> language models (akin to ChatGPT) that predict the probability of word sequences, and thus what words are most likely to come next in someone’s thoughts.</p>
<p>The researchers also worked with patients watching silent short film clips. They demonstrated that the system could be used not only to decode semantic content entertained through auditive perception, but also through visual perception.</p>
<p>Importantly, they also explicitly addressed the potential threat to a person’s mental privacy posed by this kind of technology. Jerry Tang, one of the study’s lead researchers, <a href="https://cns.utexas.edu/news/podcast/brain-activity-decoder-can-reveal-stories-peoples-minds">stated</a>:</p>
<blockquote>
<p>We take very seriously the concerns that it could be used for bad purposes and have worked to avoid that. We want to make sure people only use these types of technologies when they want to and that it helps them.</p>
</blockquote>
<p>The very fact this semantic decoder has to be trained on each person separately, with their cooperation over a long period of time, constitutes a robust safeguard. In other words, one of the major hurdles in the development of language decoders – the fact they are not universally applicable – constitutes one of the strongest safeguards against privacy violations.</p>
<p>However, while there is no risk of a malevolent company being able to read the thoughts of a random person in the street any time soon, there are nonetheless important ethical, legal and data protection concerns that must be considered as this technology develops.</p>
<p>We have already seen the <a href="https://www.nytimes.com/2018/04/04/us/politics/cambridge-analytica-scandal-fallout.html">consequences</a> of unfettered corporate access to personal data and online behaviour. Although we are a long way off from neural data being collected and processed at such scale, it is important to consider burgeoning ethical questions in the early stages of technological progress.</p>
<h2>The ethical implications are immense</h2>
<p>Losing the ability to communicate is a <a href="https://www.tandfonline.com/doi/abs/10.1080/17483107.2022.2146217">deep cut to one’s sense of self</a>. Restoring this ability gives the patient greater control over their lives and their ability to navigate the world – but it could also give other entities, such as corporations, researchers and other third parties, an uncomfortable degree of insight into, or even control over, the lives of patients.</p>
<p>Even other types of intimate biological data, such as that about our genomes or our biometrics, do not come as close to approximating our private inner lives as neural data. The ethical implications of providing access to such data to scientific and corporate entities are potentially immense.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/572536/original/file-20240131-25-g07hqb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Text of UN resolution 51/3" src="https://images.theconversation.com/files/572536/original/file-20240131-25-g07hqb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/572536/original/file-20240131-25-g07hqb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=532&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572536/original/file-20240131-25-g07hqb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=532&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572536/original/file-20240131-25-g07hqb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=532&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572536/original/file-20240131-25-g07hqb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=668&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572536/original/file-20240131-25-g07hqb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=668&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572536/original/file-20240131-25-g07hqb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=668&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">UN resolution 51/3.</span>
<span class="attribution"><a class="source" href="https://documents-dds-ny.un.org/doc/UNDOC/GEN/G22/525/01/PDF/G2252501.pdf?OpenElement">UNHRC</a></span>
</figcaption>
</figure>
<p>This is reflected in <a href="https://www.ohchr.org/en/calls-for-input/2023/call-inputs-study-human-rights-council-advisory-committee-neurotechnology-and#:%7E:text=At%20its%20fifty%2Dfirst%20session,promotion%20and%20protection%20of%20all">Resolution 51/3</a> of the UN Human Rights Council, which commissioned a study on “the impact, opportunities and challenges of neurotechnology with regard to the promotion and protection of all human rights” in time for the council’s 57th session in September 2024. However, whether the introduction of novel human rights is warranted to address the challenges posed by neurotechnology remains a hotly debated issue among human rights experts and advocacy groups.</p>
<p>The <a href="https://neurorightsfoundation.org/mission">NeuroRights Foundation</a>, based at Columbia University in New York, argues that novel rights surrounding neurotechnologies will be needed for all humans to preserve their privacy, identity, and free will. The potential vulnerability of disabled patients makes this a particularly important problem. For example, Parkinson’s disease, a neurodegenerative disease that affects movement, is co-morbid with dementia, which affects the ability to reason and think clearly.</p>
<p>In line with this approach, <a href="https://spectrum.ieee.org/neurotech-neurorights">Chile was the first country</a> that adopted legislation to address the risks inherent to neurotechnology. It not only <a href="https://courier.unesco.org/en/articles/chile-pioneering-protection-neurorights">introduced a new constitutional right</a> to mental integrity, but is also in the process of adopting a bill that bans selling neurodata, and subjects all neurotech devices to be regulated as medical devices, even those intended for the general consumer. The proposed legislation recognises the intensely personal nature of neural data and considers it <a href="https://restofworld.org/2021/chile-neuro-rights/">akin to organ tissue</a> which cannot be bought or sold, only donated. But this legislation has also faced criticism, with legal scholars <a href="https://www.sciencedirect.com/science/article/abs/pii/S2589295921000059?casa_token=A9_9ASQthlMAAAAA:FXJiHZARnjPp6IjA7jHBqHzrHCAxoTY0s9um1nWWi9rE5so52ssahLBwwwkb5YTQGKR-sznGAg">questioning</a> the need for new rights and <a href="https://link.springer.com/article/10.1007/s12152-022-09504-z#Sec1">pointing out</a> that this regime could stifle beneficial BCI research for disabled patients.</p>
<p>While the legal action taken by Chile is the most impactful and far-reaching to date, <a href="https://spanish-presidency.consilium.europa.eu/en/news/leon-declaracion-european-neurotechnology-human-rights/">other countries</a> are considering following suit by updating existing laws to address the developments in neurotechnologies.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/ybUnmQ05vX4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Chile’s pioneering neurotechnology regulation – report by Al Jazeera English.</span></figcaption>
</figure>
<p>One of the cornerstones of ethical research is the <a href="https://www.ncbi.nlm.nih.gov/books/NBK430827/#:%7E:text=Introduction,undergo%20the%20procedure%20or%20intervention.">principle of informed consent</a>. <a href="https://pubmed.ncbi.nlm.nih.gov/26497727/">Particular attention</a> must be paid to the capacity of paralysed patients and their family members to understand and consent to novel experimental therapies. Patients with a very limited ability to communicate may not be able to answer more extensive questions associated with the obtaining of informed consent, which is often more complex than a simple opt-in procedure. Also, not all potential risks and side-effects (both physical and mental) can be foreseen, making it difficult for physicians to adequately inform their patients.</p>
<p>At the same time, it is important <a href="https://link.springer.com/article/10.1007/s11948-015-9712-7">to keep in mind</a> that denying treatment to a patient whose only hope may be communicating through BCI presents a significant opportunity cost, such as a lifetime without communication, that may be very well greater than the costs of participation in experimental treatments. The appropriate balance to strike for clinicians and researchers will be challenging to determine.</p>
<p>In a burgeoning new era of big (brain) data, longstanding ethical concerns about the hacking, leaking, unauthorised use or commercial exploitation of personal data will be amplified in the case of sensitive data on a person’s thoughts or movements (as controlled through neuroprosthetics). Paralysed patients may be particularly vulnerable to neurodata theft given their reliance on caregivers, and increasingly, the BCI technologies themselves, to communicate and move around the world. Care must be taken to ensure that information disclosed by a BCI represents a patient’s true and consensual thoughts.</p>
<p>And while it is likely that the first advances in neurotech will be therapeutic in nature, such as for disabled and neurodivergent patients, future advances are likely to involve consumer applications such as <a href="https://bci.games/">entertainment</a>, as well as for <a href="https://theconversation.com/brain-computer-interfaces-could-allow-soldiers-to-control-weapons-with-their-thoughts-and-turn-off-their-fear-but-the-ethics-of-neurotechnology-lags-behind-the-science-194017#:%7E:text=For%20example%2C%20a%20soldier%20in,more%20rapid%20response%20to%20threats.">military and security</a> purposes. The growing availability of neurotechnology in a commercial context that is generally subject to far less regulation only amplifies these ethical and legal concerns.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/freedom-of-thought-is-being-threatened-by-states-big-tech-and-even-ourselves-heres-what-we-can-do-to-protect-it-220266">Freedom of thought is being threatened by states, big tech and even ourselves. Here’s what we can do to protect it</a>
</strong>
</em>
</p>
<hr>
<p>Data protection laws should be assessed on their ability to account for the new risks arising from increasing access to and collection of neurodata by organisations and entities of different types. Take the example – for the time being completely hypothetical – of using BCI to infer the thoughts of suspects in police interrogations.</p>
<p>One might say that BCI cannot be used in police interrogations as the error rate of misinterpreting a person’s neural data is currently unacceptably high, although accuracy could improve in the future. Or, one might say that BCI should never be used to “read” a person’s brain without their consent, regardless of the technology’s accuracy. Or, one might say that using BCI for interrogations is justified under certain extreme circumstances, such as when crucial information is needed to save someone’s life, and the suspect is refusing to cooperate.</p>
<p>Different people, societies, and cultures will disagree on where to draw the line. We are at an early stage of technological development and as we begin to uncover the great potential of BCI, both for therapeutic applications and beyond, the need to consider these ethical questions and their implications for legal action becomes more pressing.</p>
<h2>Decoding our neuro future</h2>
<p>This is a groundbreaking moment in our quest to understand the inner workings of our brains and minds. In the past year alone, neuroscientists have <a href="https://www.nature.com/articles/s41586-023-06094-5">reversed spinal disabilities</a>, translated MRI data into text to <a href="https://www.nature.com/articles/s41593-023-01304-%209.epdf">understand what someone is thinking</a>, and begun to <a href="https://twitter.com/neuralink/status/1661857379460468736?cxt=HHwWgMDSoeqejZAuAAAA">conduct clinical trials</a> to help people interact with objects using thoughts alone, something already seen in <a href="https://www.youtube.com/watch?v=Zcz-Hq1NP98">trials with monkeys</a> two years ago. Such developments could all lead to transformative impacts on people’s lives.</p>
<p>At the same time, it’s important to note that research such as the HuthLab study uses a very small sample, and that the training process for its semantic decoder is complex, time-consuming and expensive. Add to this the fact that fMRI, although non-invasive, is a non-wearable neuro-imaging technique, and it is clear these methods are not set to leave a strictly organised laboratory setting any time soon.</p>
<p>However, the HuthLab researchers <a href="https://cns.utexas.edu/news/podcast/brain-activity-decoder-can-reveal-stories-peoples-minds">suggest</a> that in time, fMRI could be replaced by functional near-infrared spectroscopy (fNRIS) which, by “measuring where there’s more or less blood flow in the brain at different points in time”, could give similar results to fMRI using a wearable device.</p>
<p>Certainly, the <a href="https://www.neurotech.com/investment-digest">exponential global investment</a> in the development of neurotechnologies such as this, by governments and private actors alike, shows that the world is eager to create accessible BCIs that are suited to function as medical devices, but also as commercial consumer goods. By the middle of 2021, the total investment in neurotechnology companies amounted to just over US$33 billion (around £26 billion).</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/M-slagG1OKE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Neuralink’s first human brain implant – report by Sky News.</span></figcaption>
</figure>
<p>One of the most high-profile companies is Musk’s <a href="https://neuralink.com/">Neuralink</a>. “Initial results show promising neuron spike detection,” Musk tweeted on January 29, of his neurotech startup’s <a href="https://www.npr.org/2024/01/30/1227850900/elon-musk-neuralink-implant-clinical-trial">first implanted chip in a human brain</a>. The implant is said to include 1,024 electrodes, yet is only slightly larger than the diameter of a red blood cell. <a href="https://twitter.com/neuralink/status/1716973591684653555">According to Neuralink</a>: “Its small size allows threads to be inserted with minimal damage to the [brain] cortex.”</p>
<p>While this wireless implant is currently being developed as a medical device, aiming at enhancing the quality of life for patients suffering from various neurological diseases (Neuralink’s clinical trial has enlisted people aged 22 and above living with quadriplegia), Musk <a href="https://twitter.com/elonmusk/status/1752119586470949056">stated on X-Twitter</a> that the ultimate aim is to create a device that “enables control of your phone or computer, and through them almost any device, just by thinking”.</p>
<p>Indeed, commercial neuro-imaging devices are already on the market. The <a href="https://www.spiedigitallibrary.org/journals/journal-of-biomedical-optics/volume-27/issue-07/074710/Kernel-Flow--a-high-channel-count-scalable-time-domain/10.1117/1.JBO.27.7.074710.full?webSyncID=cc96715c-8678-b272-ce9d-a31d41322dc9&sessionGUID=467762ac-1ce5-a61d-96e9-9042d3bc6d99&_ga=2.177093349.1194737154.1696754253-1060044912.1696754253&cm_mc_uid=86756417056816967542535&cm_mc_sid_50300000=84585101696754253521&SSO=1">Kernel Flow</a>, for example, is a commercially available, wearable headset that uses fNRIS technology to monitor brain activity. Another prominent player in commercial neuro-imaging, Emotiv, has developed <a href="https://www.emotiv.com/?campaignid=17057185126&adgroupid=138768698289&network=g&device=c&utm_term=emotiv%20eeg&utm_source=google&utm_medium=ppc&utm_content=644974459432&utm_campaign=Brand&hsa_acc=5401365090&hsa_cam=17057185126&hsa_grp=138768698289&hsa_ad=644974459432&hsa_src=g&hsa_tgt=kwd-343485221404&hsa_kw=emotiv%20eeg&hsa_mt=p&hsa_net=adwords&hsa_ver=3&gad=1&gclid=Cj0KCQjwpompBhDZARIsAFD_Fp9Pf4GC78tnxQw2h90QpHzibYCJenjkzWEsTArqRrXxCWkfdVmK1VkaAjeREALw_wcB">earpods incorporating EEG technology</a> that are able to monitor brain activity for signs of focus, attention and stress – with the stated ambition of boosting the wearer’s productivity at work.</p>
<p>While the era of big data has enabled increasingly personalised and complex approximations of people’s inner lives through our biometrics, genetics and online presence, nothing has been so powerful as to capture the inner workings of our minds – yet.</p>
<p>But as HuthLab’s research suggests, and Musk’s pronouncements claim, this may now not be so very far away. The dawn of a new era of brain-computer interfaces should be treated with great care and great respect – in acknowledgement of its immense potential to both help, and harm, our future generations.</p>
<hr>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=112&fit=crop&dpr=1 600w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=112&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=112&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=140&fit=crop&dpr=1 754w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=140&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/313478/original/file-20200204-41481-1n8vco4.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=140&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em>For you: more from our <a href="https://theconversation.com/uk/topics/insights-series-71218?utm_source=TCUK&utm_medium=linkback&utm_campaign=TCUKengagement&utm_content=InsightsUK">Insights series</a>:</em></p>
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<p class="fine-print"><em><span>Stephanie Sheir received funding from the EPSRC (grant number EP/V026518/1). </span></em></p><p class="fine-print"><em><span>Timo Istace receives funding from Fonds Wetenschappelijk Onderzoek Vlaanderen.</span></em></p><p class="fine-print"><em><span>Nicholas J. Kelley does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>As Elon Musk’s Neuralink begins inserting chips into human brains, we trace the history of ‘mind reading’ technology and assess the potential risks and rewardsNicholas J. Kelley, Assistant Professor in Social Psychology, University of SouthamptonStephanie Sheir, Research Associate, Trustworthy Autonomous Systems Hub, University of BristolTimo Istace, PhD Researcher in Neurotechnology and the Law, University of AntwerpLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2129552023-09-17T12:07:36Z2023-09-17T12:07:36ZWhat Canadians need to know about West Nile virus, a mosquito-borne infection that can be life-threatening<iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/what-canadians-need-to-know-about-west-nile-virus-a-mosquito-borne-infection-that-can-be-life-threatening" width="100%" height="400"></iframe>
<p>During the late summer of 1999, New York City recorded an <a href="https://doi.org/10.2105%2Fajph.92.8.1218">unusual number of cases of encephalitis</a> (inflammation of the brain). At the same time, the <a href="https://www.nationalgeographic.com/science/article/west-nile-virus-the-stranger-that-came-to-stay">Bronx Zoo</a> reported a massive death of birds and mammals. </p>
<p>The human encephalitis cases might have been attributed to a flare-up of an endemic arbovirus (<a href="https://ndc.services.cdc.gov/case-definitions/arboviral-diseases-neuroinvasive-and-non-neuroinvasive-2015/">a virus transmitted by a tick or mosquito bite</a>) such as <a href="https://www.cdc.gov/sle/index.html">St. Louis encephalitis</a>, but the concurrent bird and mammal deaths suggested the human illnesses warranted further investigation. </p>
<p>Scientists eventually identified these as the first confirmed cases of West Nile virus (WNV) in North America.</p>
<h2>West Nile virus in North America</h2>
<p>WNV was first reported in a woman with a fever in Uganda in 1937. An <a href="https://doi.org/10.2214/ajr.184.3.01840957">outbreak in Israel in 1957</a> established WNV as a cause of <a href="https://doi.org/10.3201/eid0704.017416">severe meningoencephalitis</a> (inflammation of the spinal cord and brain) in elderly patients. </p>
<p>Several clusters or medium-range outbreaks were reported from Asia, Europe and Africa in the 20th century. Finally, the virus managed to cross the Atlantic and landed in North America in 1999.</p>
<figure class="align-center ">
<img alt="Round blue particles nestled in a red matrix" src="https://images.theconversation.com/files/548213/original/file-20230914-19-x6rm98.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/548213/original/file-20230914-19-x6rm98.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=454&fit=crop&dpr=1 600w, https://images.theconversation.com/files/548213/original/file-20230914-19-x6rm98.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=454&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/548213/original/file-20230914-19-x6rm98.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=454&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/548213/original/file-20230914-19-x6rm98.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=570&fit=crop&dpr=1 754w, https://images.theconversation.com/files/548213/original/file-20230914-19-x6rm98.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=570&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/548213/original/file-20230914-19-x6rm98.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=570&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Microscopic view of West Nile virus particles in a cell.</span>
<span class="attribution"><span class="source">(NIAID)</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>In 1999, the <a href="https://www.cdc.gov/westnile/statsmaps/historic-data.html">case number</a> was limited to 62 in New York City, and there was concern about a huge surge in 2000. Fortunately, the case number in 2000 was 21, which is exceedingly low, but it had spread to New Jersey and Connecticut. The case number remained in a similar low range (only 66 cases) in 2001. </p>
<p>However, the virus hit hard the following year. In 2002, the case number rose to over 4,000 in the United States. The same year, <a href="https://www.canada.ca/en/public-health/services/diseases/west-nile-virus/surveillance-west-nile-virus.html">Canada experienced its first cases</a> in Ontario.</p>
<p>The U.S. has reported a <a href="https://www.cdc.gov/westnile/statsmaps/historic-data.html">cumulative total</a> of 56,569 cases and 2,773 deaths, while <a href="https://www.canada.ca/en/public-health/services/diseases/west-nile-virus/surveillance-west-nile-virus.html#a1">Canada has reported 6,683 cases</a> and about 150 deaths (I’m told by the Centre for Food-borne, Environmental & Zoonotic Infectious Diseases, Public Health Agency of Canada), with the highest number of cases observed in the U.S. in 2003 and in Canada in 2007.</p>
<p>This virus spread across the entire continent very quickly, and covered most of North America by 2005. However, it took almost 10 years for the virus to <a href="https://doi.org/10.1089/vbz.2010.0062">show up in British Columbia</a>. In Canada, most of the cases were found in the Prairie region (Alberta, Saskatchewan and Manitoba). <a href="https://www.cdc.gov/westnile/statsmaps/historic-data.html">In the U.S.</a>, Midwestern states have been most affected.</p>
<p>West Nile virus is an RNA virus, a close cousin of <a href="https://www.who.int/news-room/fact-sheets/detail/dengue-and-severe-dengue">Dengue</a>, <a href="http://www.bccdc.ca/health-info/diseases-conditions/yellow-fever">Yellow fever</a>, St. Louis encephalitis and <a href="http://www.bccdc.ca/health-info/diseases-conditions/zika-virus">Zika virus</a>, to name a few. It belongs to the family Flaviviridae. </p>
<h2>Symptoms and transmission</h2>
<p><a href="https://www.cdc.gov/westnile/symptoms/index.html">Approximately 80 per cent of people</a> exposed to WNV are asymptomatic. <a href="https://doi.org/10.14745/ccdr.v40i10a01">The incubation period</a> in humans is about a week; however, this ranges from two to 15 days after the virus enters the body.</p>
<p>Among symptomatic individuals, all of them experience fever, and many also experience headaches, body aches, a mild rash and swollen lymph glands to varying degrees. </p>
<p>Although most cases go unnoticed, the virus still has deadly potential. <a href="https://nccid.ca/debrief/west-nile-virus/">A small number of people</a> (around one per cent) experience severe symptoms, including encephalitis. However, over the years, the <a href="https://doi.org/10.1038/ncpneuro0176">number of neurological cases has been increasing</a>.</p>
<p>This virus is mostly <a href="https://www.who.int/news-room/fact-sheets/detail/west-nile-virus">transmitted via mosquito bites</a>; however, very rarely it could transmit via blood transfusion, organ or tissue transplants, from mother to unborn babies and through exposure to infected animals. </p>
<p>A number of birds, predominantly corvids such as crows, jays and magpies, act as reservoirs as well as <a href="https://www.biologyonline.com/dictionary/amplifier-host">amplifying hosts</a>. When an uninfected mosquito feeds on an infected bird and then bites a healthy human, the human becomes infected. </p>
<p>Humans are considered dead-end hosts, meaning that even if a mosquito feeds on an infected individual, that mosquito cannot transmit the virus to another individual <a href="https://www.who.int/news-room/questions-and-answers/item/dengue-and-severe-dengue">as can happen with the dengue virus</a>.</p>
<p>Once people are severely infected with West Nile virus, they <a href="https://www.cdc.gov/westnile/symptoms/index.html">acquire longer immunity</a>. Older people are usually at high risk for severe infection due to underlying health conditions. People with diabetes and uncontrolled hypertension <a href="https://www.canada.ca/en/public-health/services/diseases/west-nile-virus/risks-west-nile-virus.html">have a greater risk</a> of developing severe neurological disease from the West Nile virus. </p>
<h2>Diagnosis</h2>
<p>Patients who become ill with a fever and severe headache within a few days of a mosquito bite should visit their family physician or any health-care facility.</p>
<p>Because WNV is closely related to other pathogens, diagnosis is often challenging.
Patient signs and symptoms, history of mosquito bites and laboratory tests are all important when assessing patients for possible infection with West Nile virus.</p>
<p>The most common <a href="https://www.publichealthontario.ca/en/Laboratory-Services/Test-Information-Index/West-Nile-Virus-Serology">laboratory test</a> is to detect antibodies against WNV in the blood. However, WNV antibodies cross-react with dengue, Zika or other flaviviruses, so if this test is positive, an additional test is required to confirm the diagnosis. </p>
<p>This additional test is called the Plaque Reduction Neutralization Test or PRNT for short. It requires a live virus, so it must be done in a containment level 3 (CL3) laboratory. </p>
<p>The laboratory can also diagnose viral RNA using molecular tests, but interestingly, the virus often disappears from the blood when people exhibit symptoms. For encephalitic patients, cerebrospinal fluid can be used to detect the virus using molecular methods such as a polymerase chain reaction (PCR) test.</p>
<h2>Preventive measures</h2>
<p>There is no human vaccine for the West Nile virus. The most important preventive measure to avoid West Nile virus infection is to avoid mosquito bites. This seems simple but is often very challenging. </p>
<figure class="align-center ">
<img alt="Close-up view of a mosquito held with tweezers" src="https://images.theconversation.com/files/548224/original/file-20230914-17-vsdb54.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/548224/original/file-20230914-17-vsdb54.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/548224/original/file-20230914-17-vsdb54.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/548224/original/file-20230914-17-vsdb54.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/548224/original/file-20230914-17-vsdb54.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/548224/original/file-20230914-17-vsdb54.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/548224/original/file-20230914-17-vsdb54.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A Culex tarsalis mosquito, a species that can transmit West Nile virus to humans, and is found across Canada.</span>
<span class="attribution"><span class="source">(AP Photo/Rick Bowmer)</span></span>
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</figure>
<p>People should use common sense during outdoor and indoor activities. Mosquito bites can be prevented by using bug spray, wearing protective clothing and avoiding areas that may have mosquitoes during the times when the species is most active, typically dusk and dawn. </p>
<p>A few species of mosquitoes can transmit WNV to humans. Among these, two of the most common species — the Culex pipiens and Culex tarsalis — are found across Canada, and their habitat is <a href="https://ncceh.ca/resources/evidence-reviews/impacts-canadas-changing-climate-west-nile-virus-vectors">predicted to expand with climate change</a>. Mosquitoes not only transmit WNV, but also transmit <a href="https://www.canada.ca/en/public-health/services/laboratory-biosafety-biosecurity/pathogen-safety-data-sheets-risk-assessment/california-serogroup-pathogen-safety-data-sheet.html">California serogroup viruses</a>, which cause encephalitis, as well as <a href="https://www.canada.ca/en/public-health/services/laboratory-biosafety-biosecurity/pathogen-safety-data-sheets-risk-assessment/eastern-equine-encephalitis.html">eastern equine encephalitis</a> viruses. </p>
<p>There is also no specific treatment for West Nile virus; medical management is supportive. Patients with severe symptoms often require pain control for headaches and medication and rehydration to treat nausea and vomiting. </p>
<p><a href="https://www.canada.ca/en/public-health/services/diseases/west-nile-virus/surveillance-west-nile-virus/west-nile-virus-weekly-surveillance-monitoring.html">So far in 2023</a>, only a <a href="https://www.cbc.ca/news/canada/hamilton/hamilton-west-nile-virus-2023-1.6957260">few human cases</a> have been identified in Ontario. However, a few mosquito pools in Manitoba and Ontario also tested positive, and also a few WNV-positive birds were found in Saskatchewan, Manitoba, Ontario and Québec.</p>
<p>No matter how many cases we are seeing, everyone is advised to take precautions against mosquito bites to avoid these life-threatening diseases.</p><img src="https://counter.theconversation.com/content/212955/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Muhammad Morshed does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>West Nile virus arrived in North America in 1999 and spread across the continent by 2005. Here’s what you need to know about this mosquito-borne pathogen.Muhammad Morshed, Clinical Professor, Department of Pathology and Laboratory Medicine, University of British ColumbiaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2082812023-08-17T01:00:49Z2023-08-17T01:00:49ZWhat is sudden unexpected death in epilepsy, and what causes it?<figure><img src="https://images.theconversation.com/files/541171/original/file-20230804-17-ze86rg.jpg?ixlib=rb-1.1.0&rect=20%2C20%2C6689%2C4446&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>When 20-year-old Disney Channel star Cameron Boyce died of “sudden unexpected death in epilepsy” (known as <a href="https://www.epilepsy.com/complications-risks/early-death-sudep">SUDEP</a>) in 2019, his parents had not even heard of the condition.</p>
<p>“We didn’t know about SUDEP. We have family members who are doctors who never heard of SUDEP,” Cameron’s father Victor said in an <a href="https://www.healthline.com/health/epilepsy/cameron-boyce-foundation-interview">interview</a>. </p>
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<p>We were clueless, completely clueless. The first time we heard [of] SUDEP is when the coroner told us that’s what took our son.</p>
</blockquote>
<p>Most of us have heard of <a href="https://www.epilepsy.com/what-is-epilepsy">epilepsy</a>, a brain condition that causes recurrent and spontaneous seizures. Lesser known to the public is that seizures can lead to an uncommon but fatal complication known as sudden unexpected death in epilepsy.</p>
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<h2>What is sudden unexpected death in epilepsy?</h2>
<p>Sudden unexpected death in epilepsy is when someone with epilepsy dies without any warning and there is no other cause found. It often occurs immediately after a night-time convulsive seizure. Victims are often found in bed and lying face down. </p>
<p>While this can occur at any age, it particularly affects young people – the average age at death is only <a href="https://n.neurology.org/content/93/3/e227">26 years</a>.</p>
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<p>The risk of sudden unexpected death in epilepsy is highest in those who have <a href="https://www.epilepsy.com/what-is-epilepsy/seizure-types/tonic-clonic-seizures">convulsive or “tonic-clonic” seizures</a>. With these types of seizures, the muscles stiffen, there is loss of consciousness, and the body starts jerking rhythmically. </p>
<p>This can cause a fast heart rate, as well as long pauses to breathing, which decrease oxygen levels. These seizures can place a lot of stress on the body.</p>
<p>Even one convulsive seizure in the past year can increase the risk of sudden unexpected death in epilepsy. In one Swedish study, having one convulsive seizure and not sharing a bedroom (meaning no-one is there to intervene if a seizure occurs in the night) made the condition <a href="https://n.neurology.org/content/94/4/e419">67 times more likely</a> than those who do not have convulsive seizures and share a bedroom. As the number of convulsive seizures increase, the risk of sudden unexpected death also increases.</p>
<p>Sudden unexpected death in epilepsy is the leading cause of death from epilepsy and accounts for over <a href="https://n.neurology.org/content/98/3/e213">80% of epilepsy deaths</a>. </p>
<p>While the overall risk of SUDEP is low, with about 1 in 1,000 people with epilepsy affected each year, this risk increases to 1 in 150 in those with poorly controlled <a href="https://www.thelancet.com/journals/laneur/article/PIIS1474-4422(08)70202-3/fulltext">seizures</a>. The <a href="https://www.nejm.org/doi/full/10.1056/nejmoa0911610">risk</a> increases with time, as epilepsy is often a lifelong condition, and the longer the exposure, the higher the risk. </p>
<p>But these figures are thought to be an underestimate. Because deaths commonly occur at night, they aren’t often witnessed, limiting what information there is about the time of death – for instance, whether there a seizure right before death. Often, victims are found deceased in bed and a history of epilepsy is overlooked as the cause of death.</p>
<p>People with epilepsy often have other serious medical problems such as <a href="https://www.ahajournals.org/doi/10.1161/JAHA.121.021170">heart disease</a>, which can make identifying the cause of death difficult. </p>
<p>Autopsy findings are often inconclusive or <a href="https://n.neurology.org/content/89/9/878">attributed to heart issues</a>, as even among forensic specialists there is <a href="https://n.neurology.org/content/89/9/886">limited awareness</a> that epilepsy can cause sudden death.</p>
<h2>Do we know what causes sudden unexpected death in epilepsy?</h2>
<p>It’s still unclear why one person can have hundreds of convulsive seizures in their lifetime and won’t die of sudden unexpected death in epilepsy, and yet another can die after only a handful. </p>
<p>We think this is because there are <a href="https://www.epilepsy.com/complications-risks/early-death-sudep/how-sudep-occurs">many different causes</a>. </p>
<p>Looking at sudden unexpected death in epilepsy cases <a href="https://www.thelancet.com/journals/laneur/article/PIIS1474-4422(13)70214-X/fulltext">that happened in hospital</a>, researchers found that in all cases, a convulsive seizure caused a “flat-lining” of brain activity, which stopped the heart beat and breathing – all within minutes, causing rapid death. Survivors in this study all received prompt resuscitation within minutes.</p>
<p>But in some people, seizures can trigger dangerous irregular heart <a href="https://n.neurology.org/content/98/19/e1923.long">rhythms</a> – which may be <a href="https://cp.neurology.org/content/11/5/e747">another cause</a> of the sudden death.</p>
<p>Some genetic conditions can impair how molecules responsible for electrical conduction in the heart and brain function. This can increase the risk of sudden unexpected death in epilepsy by making <a href="https://onlinelibrary.wiley.com/doi/10.1002/ana.24596">epilepsy and abnormal heart conditions</a> more likely to occur together, heightening the risk of death.</p>
<p>Seizures can deprive the major organs of oxygen. Over time, repeated decreases in oxygen levels can cause damage to not only the heart, but also to the brain. </p>
<p>In people who died of sudden unexpected death in epilepsy, areas of the brain that control breathing and heart function had <a href="https://onlinelibrary.wiley.com/doi/10.1111/epi.14689">shrunk</a>. Over time, this may increase the risk of sudden unexpected death in epilepsy by lowering the brain’s ability to control vital functions.</p>
<h2>I or a loved one have epilepsy. What can we do?</h2>
<p>Unfortunately, people with epilepsy and their families are often not <a href="https://www.ilae.org/files/ilaeGuideline/AES_SUDEP_Position_Statement_2019.pdf">counselled</a> on sudden unexpected death in epilepsy and its risks. All newly diagnosed epilepsy patients should be informed about these risks at the time of diagnosis or shortly afterwards.</p>
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<p>Individual risk varies. For most people with epilepsy, the overall risk will be low. Control of convulsive seizures is associated with the most significant risk reduction. </p>
<p>Most of the time this is achieved with the use of one or more <a href="https://www.epilepsy.com/stories/summary-anti-seizure-medications">epilepsy medications</a>. </p>
<p>In people who don’t respond to epilepsy medications, <a href="https://www.mayoclinic.org/tests-procedures/epilepsy-surgery/about/pac-20393981">brain surgery</a>, <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/epi.17329#pane-pcw-references">implantable neurostimulators</a>, or <a href="https://www.epilepsy.com/treatment/dietary-therapies/ketogenic-diet">dietary therapies</a> may offer some people hope in decreasing seizure frequency.</p>
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Read more:
<a href="https://theconversation.com/what-are-ketogenic-diets-can-they-treat-epilepsy-and-brain-cancer-83401">What are ketogenic diets? Can they treat epilepsy and brain cancer?</a>
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<p>It’s important to remember sudden unexpected death in epilepsy can happen to anyone with epilepsy – even those with well-controlled epilepsy. </p>
<p>Taking medications as prescribed and not missing doses, getting a good night’s sleep, avoiding alcohol and recreational drugs, and managing stress may reduce the risk of sudden unexpected death in epilepsy by making <a href="https://www.epilepsy.com/what-is-epilepsy/seizure-triggers">seizures less likely</a>. </p>
<p>For some people who continue to have convulsive seizures, <a href="https://n.neurology.org/content/94/4/e419">sharing a bedroom</a>, or <a href="https://epilepsyfoundation.org.au/understanding-epilepsy/epilepsy-and-seizure-management-tools/seizure-monitors-devices/">night-time monitoring devices</a> may offer peace of mind and help with sudden unexpected death in epilepsy risk.</p>
<p>The causes of sudden unexpected death in epilepsy are many – understanding these will help develop targeted treatments. We need to develop tests that can identify people at high risk so we can optimise prevention strategies. </p>
<p>The development of night-time monitoring systems to identify dangerous seizures in the home and alert caregivers or emergency services is currently underway, and are sorely needed.</p><img src="https://counter.theconversation.com/content/208281/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Shobi Sivathamboo receives funding from the National Institutes of Health. She is affiliated with The International League Against Epilepsy SUDEP Task Force.</span></em></p>Most of us have heard of epilepsy. Lesser known to the public is that seizures can lead to an uncommon but fatal complication known as sudden unexpected death in epilepsy.Shobi Sivathamboo, Research Fellow, Monash UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1982202023-02-22T12:54:26Z2023-02-22T12:54:26ZPeople produce endocannabinoids – similar to compounds found in marijuana – that are critical to many bodily functions<figure><img src="https://images.theconversation.com/files/510907/original/file-20230217-380-5ni8j3.jpg?ixlib=rb-1.1.0&rect=30%2C38%2C5077%2C3339&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A healthy endocannabinoid system is critical to the human body’s immune functions.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/older-hispanic-woman-lifting-weights-in-living-room-royalty-free-image/546825853?phrase=energy%20exercise&adppopup=true">Jose Luis Pelaez Inc/Digital Vision via Getty Images</a></span></figcaption></figure><p>Over the past two decades, a great deal of attention has been given to marijuana – also known as pot or weed. As of early 2023, marijuana has been <a href="https://www.usnews.com/news/best-states/articles/where-is-marijuana-legal-a-guide-to-marijuana-legalization">legalized for recreational use in 21 states</a> and Washington, D.C., and the use of <a href="https://www.mayoclinic.org/healthy-lifestyle/consumer-health/in-depth/medical-marijuana/art-20137855">marijuana for medical purposes</a> has grown significantly during the <a href="https://nap.nationalacademies.org/catalog/24625/the-health-effects-of-cannabis-and-cannabinoids-the-current-state">last 20 or so years</a>. </p>
<p>But few people know that the human body naturally produces chemicals that are very similar to delta-9-tetrahydrocannabinol, or THC, the psychoactive compound in marijuana, which comes from the <a href="https://doi.org/10.3389/fpls.2016.00019"><em>Cannabis sativa</em> plant</a>. These substances are called endocannabinoids, and they’re <a href="https://doi.org/10.3390%2Fani9090686">found across all vertebrate species</a>. </p>
<p>Evolutionarily, the appearance of endocannabinoids in vertebrate animals predates that of <em>Cannabis sativa</em> by <a href="https://doi.org/10.1300/J175v02n01_04">about 575 million years</a>. </p>
<p>It is as if the human body has its own version of a marijuana seedling inside, constantly producing small amounts of endocannabinoids.</p>
<p>The similarity of endocannabinoids to THC, and their importance in maintaining human health, have raised significant interest among scientists to further study their role in health and disease, and potentially use them as therapeutic targets to treat human diseases.</p>
<p>THC <a href="https://doi.org/10.1038/sj.bjp.0706406">was first identified</a> in 1964, and is just one of more than 100 compounds found in marijuana that are <a href="https://www.cdc.gov/marijuana/health-effects/index.html">called cannabinoids</a>.</p>
<p><a href="https://doi.org/10.1016/j.tips.2015.02.008">Endocannabinoids were not discovered</a> until 1992. Since then, research has revealed that they are critical for many important physiological functions that <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3997295/">regulate human health</a>. An imbalance in the production of endocannabinoids, or in the body’s responsiveness to them, <a href="https://doi.org/10.1111%2Ffebs.12260">can lead to major clinical disorders</a>, including obesity as well as neurodegenerative, cardiovascular and inflammatory diseases. </p>
<p>We <a href="https://scholar.google.com/citations?user=jJVj3sUAAAAJ&hl=en">are immunologists</a> who have been <a href="https://scholar.google.com/citations?user=af7TahQAAAAJ&hl=en">studying the effects of marijuana cannabinoids and vertebrate endocannabinoids</a> on inflammation and cancer for more than two decades. <a href="https://doi.org/10.1016%2Fj.phrs.2009.03.019">Research in our laboratory</a> has shown that endocannabinoids <a href="https://theconversation.com/what-is-inflammation-two-immunologists-explain-how-the-body-responds-to-everything-from-stings-to-vaccination-and-why-it-sometimes-goes-wrong-193503">regulate inflammation</a> and other immune functions. </p>
<h2>What is the endocannabinoid system?</h2>
<p>A variety of tissues in the body, including brain, muscle, fatty tissue and immune cells, <a href="https://pubmed.ncbi.nlm.nih.gov/19675519/">produce small quantities of endocannabinoids</a>. There are <a href="https://doi.org/10.1016/j.phrs.2009.03.019">two main types of endocannabinoids</a>: anandamide, or AEA, and 2-arachidonoyl glycerol, known as 2-AG. Both of them can activate the body’s cannabinoid receptors, which receive and process chemical signals in cells. </p>
<p>One of these receptors, called CB1, is <a href="https://doi.org/10.3390%2Fijms19030833">found predominantly in the brain</a>. The other, called CB2, is <a href="https://doi.org/10.4155/fmc.09.93">found mainly in immune cells</a>. It is primarily through the activation of these two receptors that endocannabinoids control many bodily functions.</p>
<p>The receptors can be compared to a “lock” and the endocannabinoids a “key” that can open the lock and gain entry into the cells. All these endocannabinoid receptors and molecules together are referred to as the endocannabinoid system. </p>
<p>The cannabis plant contains another compound called cannabidiol, or CBD, which has <a href="https://theconversation.com/cbd-is-not-a-cure-all-heres-what-science-says-about-its-real-health-benefits-186901">become popular</a> for its medicinal properties. Unlike THC, CBD doesn’t have psychoactive properties because it <a href="https://doi.org/10.1146%2Fannurev-neuro-070815-014038">does not activate CB1 receptors in the brain</a>. Nor does it <a href="https://doi.org/10.1038/sj.bjp.0707442">activate the CB2 receptors</a>, meaning that its action on immune cells is independent of CB2 receptors. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/511480/original/file-20230221-2556-95l7i5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Textbook illustration of the human endocannabinoid system, highlighting the role of CB1 and CB2 receptors." src="https://images.theconversation.com/files/511480/original/file-20230221-2556-95l7i5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/511480/original/file-20230221-2556-95l7i5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=960&fit=crop&dpr=1 600w, https://images.theconversation.com/files/511480/original/file-20230221-2556-95l7i5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=960&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/511480/original/file-20230221-2556-95l7i5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=960&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/511480/original/file-20230221-2556-95l7i5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1206&fit=crop&dpr=1 754w, https://images.theconversation.com/files/511480/original/file-20230221-2556-95l7i5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1206&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/511480/original/file-20230221-2556-95l7i5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1206&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Endocannabinoid receptors are found throughout most of the human body.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/human-endocannabinoid-system-vertical-royalty-free-illustration/1178997969">About time/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<h2>Role of endocannabinoids in the body</h2>
<p>The euphoric “high” feeling that people experience when using marijuana comes from THC activating the CB1 receptors in the brain. </p>
<p>But when endocannabinoids activate CB1 receptors, by comparison, they do not cause a marijuana high. One reason is that the body <a href="https://doi.org/10.1038/npp.2017.130">produces them in smaller quantities</a> than the typical amount of THC in marijuana. The other is that <a href="https://doi.org/10.1021%2Fcr0782067">certain enzymes break them down</a> rapidly after they carry out their cellular functions.</p>
<p>However, there is growing evidence that certain activities may release mood-elevating endocannabinoids. Some research suggests that the relaxed, euphoric feeling you get after exercise, called a “<a href="https://theconversation.com/the-runners-high-may-result-from-molecules-called-cannabinoids-the-bodys-own-version-of-thc-and-cbd-170796">runner’s high</a>,” results from the <a href="https://www.scientificamerican.com/article/new-brain-effects-behind-runner-s-high/">release of endocannabinoids</a> <a href="https://runningmagazine.ca/health-nutrition/new-study-confirms-endorphins-arent-the-cause-of-the-runners-high/">rather than from endorphins</a>, as previously thought.</p>
<p>The endocannabinoids <a href="https://doi.org/10.3390/ijms22179472">regulate several bodily functions</a> such as sleep, mood, appetite, learning, memory, body temperature, pain, immune functions and fertility. They control some of these functions by regulating nerve cell signaling in the brain. Normally, nerve cells communicate with one another at junctions called synapses. The endocannabinoid system in the brain regulates this communication at synapses, which explains its ability to affect a wide array of bodily functions. </p>
<h2>The elixir of endocannabinoids</h2>
<p>Research in our laboratory has shown that <a href="https://doi.org/10.1002/eji.201546181">certain cells of the immune system produce endocannabinoids</a> that can regulate inflammation and other immune functions through the activation of CB2 receptors.</p>
<p>In addition, we have shown that <a href="https://doi.org/10.1124/mol.108.047035">endocannabinoids are highly effective in lessening the debilitating effects of autoimmune diseases</a>. These are diseases in which the immune system goes haywire and <a href="https://medlineplus.gov/autoimmunediseases.html">starts destroying the body’s organs and tissues</a>. Examples include <a href="https://medlineplus.gov/multiplesclerosis.html">multiple sclerosis</a>, <a href="https://doi.org/10.1124/mol.108.047035">lupus</a>, <a href="https://www.hopkinsmedicine.org/health/conditions-and-diseases/hepatitis">hepatitis</a> and <a href="https://www.niams.nih.gov/health-topics/arthritis">arthritis</a>. </p>
<p>Recent research suggests that migraine, fibromyalgia, irritable bowel syndrome, post-traumatic stress disorder and bipolar disease are all <a href="https://doi.org/10.1089/can.2016.0009">linked to low levels of endocannabinoids</a>.</p>
<p>In a 2022 study, researchers found that a defect in a gene that helps produce endocannabinoids causes <a href="https://doi.org/10.1038/s41467-022-31168-9">early onset of Parkinson’s disease</a>. Another 2022 study linked the same gene defect to <a href="https://doi.org/10.1093/brain/awac223">other neurological disorders</a>, including developmental delay, poor muscle control and vision problems. </p>
<p>Other research has shown that people with a defective form of CB1 receptors <a href="https://doi.org/10.1371/journal.pone.0187926">experience increased pain sensitivity</a> such as migraine headaches and suffer from sleep and memory disorders and anxiety. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/510714/original/file-20230216-14-6r2f4a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/510714/original/file-20230216-14-6r2f4a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/510714/original/file-20230216-14-6r2f4a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=495&fit=crop&dpr=1 600w, https://images.theconversation.com/files/510714/original/file-20230216-14-6r2f4a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=495&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/510714/original/file-20230216-14-6r2f4a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=495&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/510714/original/file-20230216-14-6r2f4a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=622&fit=crop&dpr=1 754w, https://images.theconversation.com/files/510714/original/file-20230216-14-6r2f4a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=622&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/510714/original/file-20230216-14-6r2f4a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=622&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The endocannabinoid system – consisting of the endocannabinoids and the cannabinoid receptors – regulates nerve cell communication at the synapse, thereby playing a role in a variety of bodily functions.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/endocannabinoid-system-royalty-free-illustration/1392987232?phrase=endocannabinoid%20system&adppopup=true">Carolina Hrejsa, CMI/iStock/Getty Images Plus via Getty Images</a></span>
</figcaption>
</figure>
<h2>The likeness between marijuana and endocannabinoids</h2>
<p>We believe that the medicinal properties of THC may be linked to the molecule’s ability to compensate for a deficiency or defect in the production or functions of the endocannabinoids. </p>
<p>For example, scientists have found that people who experience certain types of chronic pain may have <a href="https://doi.org/10.3390/molecules27144662">decreased production of endocannabinoids</a>. People who consume marijuana for medicinal purposes <a href="https://www.nationalacademies.org/news/2017/01/health-effects-of-marijuana-and-cannabis-derived-products-presented-in-new-report">report significant relief from pain</a>. Because the THC in marijuana <a href="https://dx.doi.org/10.1001/jama.2018.16202">is the cannabinoid that reduces pain</a>, it may be helping to compensate for the decreased production or functions of endocannabinoids in such patients. </p>
<p>Deciphering the role of endocannabinoids is still an emerging area of health research. Certainly much more research is needed to decipher their role in regulating different functions in the body. </p>
<p>In our view, it will also be important to continue to unravel the relationship between defects in the endocannabinoid system and the development of various diseases and clinical disorders. We think that the answers could hold great promise for the development of new therapies using the body’s own cannabinoids.</p><img src="https://counter.theconversation.com/content/198220/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Prakash Nagarkatti receives funding from the National Institutes of Health and the National Science Foundation. </span></em></p><p class="fine-print"><em><span>Mitzi Nagarkatti receives funding from National Institutes of Health. </span></em></p>A THC-like substance that occurs naturally in humans and other vertebrates helps maintain immunity, memory, nerve function and more – and research suggests a lack of it can harm health.Prakash Nagarkatti, Professor of Pathology, Microbiology and Immunology, University of South CarolinaMitzi Nagarkatti, Professor of Pathology, Microbiology and Immunology, University of South CarolinaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1925702022-12-08T13:32:46Z2022-12-08T13:32:46ZPeople can have food sensitivities without noticeable symptoms – long-term consumption of food allergens may lead to behavior and mood changes<figure><img src="https://images.theconversation.com/files/499637/original/file-20221207-18-b6a7kw.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2121%2C1412&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Asymptomatic sensitization may lead people to continue consuming food allergens, causing hidden neurological issues.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/young-woman-in-striped-shirt-from-back-choosing-royalty-free-image/1357286617">Garetsworkshop/iStock via Getty Images Plus</a></span></figcaption></figure><p>The prevalence of food allergies is increasing worldwide, <a href="https://doi.org/10.1111/j.1399-3038.2011.01145.x">approaching an epidemic level</a> in some regions. In the U.S. alone, <a href="https://www.foodallergy.org/resources/facts-and-statistics">approximately 10% of children and adults</a> suffer from food allergies, with allergies to cow’s milk, eggs, peanuts and tree nuts being the most common. Some patients have mild symptoms that might not need medical attention, leaving these cases unreported. </p>
<p>Food allergies, or food hypersensitivities, result from the overreaction of the immune system to typically harmless proteins in food. They can manifest as a <a href="https://acaai.org/allergies/allergic-conditions/food/">spectrum of symptoms</a>, ranging from itching, redness and swelling for milder reactions, to vomiting, diarrhea, difficulty breathing and other potentially life-threatening symptoms for severe reactions.</p>
<p>Besides self-reporting, food allergies can be <a href="https://acaai.org/allergies/testing-diagnosis/">diagnosed by exposing patients</a> to trace amounts of offending proteins, or allergens, via their mouth or skin and observing their immediate reactions. More commonly, doctors use blood tests to measure the levels of <a href="https://www.aaaai.org/tools-for-the-public/allergy,-asthma-immunology-glossary/immunoglobulin-e-(ige)-defined">immunoglobulin E, or IgE</a>, a specialized antibody that the immune system uses to identify allergens and trigger a response. Although healthy individuals may have low levels of IgE in the blood, patients with food allergies have much higher levels that increase their risk of having severe allergic reactions.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/499636/original/file-20221207-16-gmhxjg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Patient undergoing skin-prick allergy test on arm" src="https://images.theconversation.com/files/499636/original/file-20221207-16-gmhxjg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/499636/original/file-20221207-16-gmhxjg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/499636/original/file-20221207-16-gmhxjg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/499636/original/file-20221207-16-gmhxjg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/499636/original/file-20221207-16-gmhxjg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/499636/original/file-20221207-16-gmhxjg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/499636/original/file-20221207-16-gmhxjg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Skin-prick allergy tests involve exposing patients to trace amounts of an allergen and observing their reactions.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/immunologist-doing-skin-prick-allergy-test-on-a-royalty-free-image/1288998568">ronstik/iStock via Getty Images</a></span>
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<p>But <a href="https://doi.org/10.1159%2F000517824">some people</a> who test positive on skin-prick allergy tests with moderate increases in IgE don’t notice any allergy-related symptoms when they eat the allergen. This condition is sometimes referred to as <a href="https://www.verywellhealth.com/what-is-sensitization-82988">asymptomatic sensitization</a>. In many cases, people with this condition may not even be aware that they have a food hypersensitivity. </p>
<p>Are they truly asymptomatic, though? Or are there effects within their body that they aren’t aware of?</p>
<p>I am a <a href="https://scholar.google.com/citations?user=kXRRwk4AAAAJ&hl=en">neuroscientist</a> studying how the brain is affected by food allergies. I became interested in this topic when I found that some of my family members had a hypersensitivity to cow’s milk. Some totally avoid dairy products because they have experienced severe, life-threatening symptoms. Those who don’t have typical allergic reactions occasionally eat dairy, but appear to develop seemingly unrelated illnesses a day or two later.</p>
<p>What I and other researchers have found is that food allergens can affect your brain and behavior if you’re hypersensitized, even if you don’t have typical food allergy symptoms.</p>
<h2>Food allergies linked to behavioral disorders</h2>
<p>Researchers have suspected food hypersensitivities to be a potential cause for behavioral disorders for decades.</p>
<p>A <a href="https://doi.org/10.1097/00007611-194908000-00017">1949 case report</a> described behavioral and mood disturbances in patients after they ate certain foods, such as milk and eggs. Their symptoms improved after removing the suspected foods from their diet, suggesting that a food hypersensitivity was the likely culprit. However, I was intrigued that the patients had been able to eat the offending foods up until they chose to avoid them. In other words, they were asymptomatically sensitized, or tolerant, to the allergens.</p>
<p>Several recent studies in people have supported the association between food allergies and various neuropsychiatric disorders, including <a href="https://doi.org/10.1111/all.12829">depression, anxiety</a>, <a href="https://doi.org/10.1016/j.aller.2016.03.001">attention-deficit/hyperactivity disorder</a> and <a href="https://doi.org/10.1002/aur.2106">autism</a>. They strengthen the possibility that some reactions to food allergens could involve the nervous system and manifest as behavioral disorders.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/xyQY8a-ng6g?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The food you eat can affect your brain in many ways.</span></figcaption>
</figure>
<p>However, the idea of food hypersensitivity causing neuropsychiatric disorders is still controversial because of inconsistencies across studies. Differences in the types of allergies, ethnic backgrounds, dietary habits and other factors among the study participants can produce conflicting results. More importantly, some studies included those with self-reported food allergies, while others included only those with lab-confirmed food allergies. This limited investigations to only symptomatic individuals.</p>
<h2>Food hypersensitivity, brain and behavior</h2>
<p><a href="https://doi.org/10.1016/j.bbi.2021.03.002">My laboratory tested</a> whether food allergens could manifest as behavioral symptoms, particularly in asymptomatically sensitized individuals. We wanted to find out whether eating offending foods could lead to brain inflammation and behavioral changes after sensitization, even in the absence of other obvious severe reactions.</p>
<p>To minimize the individual differences found in human studies, we decided to work with mice. We sensitized mice of the same age and genetic background to the common milk allergen β-lactoglobulin, or BLG, and fed them the same diet in the same room. We found that while <a href="https://doi.org/10.1016/j.bbi.2021.03.002">BLG-sensitized mice</a> produced moderately but significantly elevated levels of IgE, they did not show immediate allergic reactions. They could even eat food containing the milk allergen for two weeks without showing any obvious symptoms, despite maintaining elevated levels of IgE. This indicated that they were asymptomatically sensitized.</p>
<p>We then observed whether they showed any changes in emotionally driven behavior. Because we could not ask mice how they felt, we deduced their “feelings” by noting changes from their normal, survival-oriented behavior. Mice instinctively explore their environment to search for food and shelter while avoiding potential danger. However, “anxious” mice tend to spend more time hiding to play it safe. We identified “depressed” mice by briefly holding them by the tail. Most mice will keep fighting to get out of the uncomfortable predicament, while depressed mice quickly give up.</p>
<p>Our experiments were designed to simulate situations where asymptomatically sensitized individuals would eat either a large amount of an offending food in one day or small amounts every day for a few weeks. We mimicked these situations by placing a large amount of the milk allergen directly into the stomach of sensitized mice with a feeding tube, or giving them an allergen-containing mouse chow to eat the allergen a little at a time.</p>
<p>Interestingly, BLG-sensitized mice showed <a href="https://doi.org/10.1016/j.bbi.2021.03.002">anxiety-like behavior</a> one day after receiving a large amount of the allergen. Another group of sensitized mice developed <a href="https://doi.org/10.3390/cells11040738">depression-like behavior</a> after eating small amounts of allergen for two weeks. In addition, BLG-sensitized mice showed signs of brain inflammation and neuronal damage, suggesting that changes in the brain may be responsible for their behavioral symptoms.</p>
<p>We also investigated the <a href="https://doi.org/10.3389/falgy.2022.870628">long-term effect</a> of allergen consumption by keeping BLG-sensitized mice on the allergen-containing diet for one month. We found that IgE levels declined in sensitized mice by the end of the month, indicating that continually eating small amounts of the allergen led to decreased immune responses, or “desensitization.” In contrast, signs of brain inflammation remained, suggesting that the harmful effect of allergens persisted in the brain.</p>
<h2>Chronic brain inflammation</h2>
<p>Researchers have yet to study prolonged brain inflammation, or neuroinflammation, in people who are asymptomatically sensitized. In general, though, <a href="https://doi.org/10.1172/JCI90609">chronic neuroinflammation</a> is a known contributor to neurodegenerative diseases, such as multiple sclerosis and Alzheimer’s disease, although the exact causes of these diseases are unknown. A better understanding of the role allergens play in neuroinflammation can help researchers clarify whether food allergens trigger chronic inflammation that can lead to these diseases.</p>
<p>This knowledge could be especially important for patients undergoing <a href="https://www.aaaai.org/Tools-for-the-Public/Allergy,-Asthma-Immunology-Glossary/Oral-Immunotherapy-Defined">oral immunotherapy</a>, an approach to allergy treatment that involves incrementally ingesting small amounts of allergens over time. The goal is to desensitize the immune system and reduce the incidence of anaphylaxis, or life-threatening allergic reactions. In 2020, the U.S. Food and Drug Administration <a href="https://www.fda.gov/news-events/press-announcements/fda-approves-first-drug-treatment-peanut-allergy-children">approved a standardized form of peanut allergens</a> to prevent anaphylaxis in eligible pediatric patients. However, its possible long-term effect on the nervous system is unknown.</p>
<p>Food allergens can affect the brain and behavior of seemingly asymptomatic people, making them not so asymptomatic neurologically. Considering how your brain responds to the food you eat puts a whole new meaning to the phrase “you are what you eat.”</p><img src="https://counter.theconversation.com/content/192570/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kumi Nagamoto-Combs receives funding from the National Institute of Allergy and Infectious Disease and the National Institute on Aging. </span></em></p>Food allergies have been linked to behavioral and mood disorders, including depression, anxiety and ADHD.Kumi Nagamoto-Combs, Assistant Professor of Biomedical Sciences, University of North DakotaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1947672022-11-18T17:18:09Z2022-11-18T17:18:09ZThe risk of seizures and epilepsy is higher after COVID than after the flu – new research<figure><img src="https://images.theconversation.com/files/495707/original/file-20221116-26-kgd3xh.jpg?ixlib=rb-1.1.0&rect=0%2C26%2C4500%2C2964&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/closeup-ct-scan-67-year-old-473967136">hutpaza/Shutterstock</a></span></figcaption></figure><p>Epilepsy is one of the most common neurological disorders, affecting roughly <a href="https://www.who.int/publications/i/item/epilepsy-a-public-health-imperative">50 million people</a> around the world. It’s a condition characterised by seizures which involve episodic, abnormal activity in nerve cells in the brain. </p>
<p>People can have convulsive seizures, where the body stiffens and shakes. There are also more subtle seizures during which people may, for example, lose awareness for short periods of time. While epilepsy always involves seizures, some people can have seizures without being diagnosed with epilepsy.</p>
<p>Epilepsy is more common <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(19)33064-8/fulltext">as we get older</a>, and the main risk factor for the condition in later life is stroke. Given that COVID affects older adults most severely and <a href="https://pubmed.ncbi.nlm.nih.gov/33879319/">can result in stroke</a>, some might speculate that COVID could see more people develop epilepsy. Whether this is actually the case, though, has been difficult to prove. </p>
<p>In <a href="https://n.neurology.org/content/early/2022/11/16/WNL.0000000000201595">a new study</a>, we’ve found that the risk of seizures or epilepsy following a COVID infection is significantly higher than after an influenza infection.</p>
<p>We know that COVID is associated with psychiatric and neurological symptoms <a href="https://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(21)00084-5/fulltext">such as anxiety</a> and <a href="https://www.science.org/doi/10.1126/science.abm2052">difficulty with memory</a>. Many early studies exploring the impact of COVID on the brain, however, focused on the immediate period after infection or had low patient numbers.</p>
<p>To try to more definitively answer whether COVID is associated with epilepsy or seizures, we looked at the health records of people who had been infected with COVID. We then carefully matched them (so that they were similar in characteristics like age, sex and medical conditions) with a group of people who had been infected with influenza. </p>
<p>Each group consisted of 152,754 people, none of whom had previously been diagnosed with epilepsy or recurrent seizures. We compared the incidence of epilepsy and seizures between the two groups over a six month period following the initial infection. </p>
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Read more:
<a href="https://theconversation.com/covid-19s-impacts-on-the-brain-and-mind-are-varied-and-common-new-research-161215">COVID-19's impacts on the brain and mind are varied and common – new research</a>
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<h2>What we found</h2>
<p>The rate of new cases of epilepsy or seizures was 0.94% in the people who had COVID, compared with 0.6% in those who had influenza. While the overall risk of seizures is therefore small, these cases show that people who had COVID were 55% more likely to develop epilepsy or seizures over the next six months than people who had influenza.</p>
<p>We then looked to see if certain groups were particularly susceptible to seizures or epilepsy after COVID. We found that, compared to influenza, children aged under 16 and people who were not hospitalised were more likely to develop epilepsy or seizures.</p>
<p>There was also a delay to when children and non-hospitalised patients experienced seizures or epilepsy, perhaps explaining why this phenomenon has not been detected in studies of shorter duration.</p>
<p>Severe infections can make people more susceptible to seizures, so it’s possible that if someone is hospitalised for either COVID or the flu that seizures will manifest as part of the acute illness.</p>
<figure class="align-center ">
<img alt="Three children walking in a forrest." src="https://images.theconversation.com/files/495714/original/file-20221116-12-11pzf8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/495714/original/file-20221116-12-11pzf8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/495714/original/file-20221116-12-11pzf8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/495714/original/file-20221116-12-11pzf8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/495714/original/file-20221116-12-11pzf8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/495714/original/file-20221116-12-11pzf8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/495714/original/file-20221116-12-11pzf8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">The increased risk was more noticeable in children than adults.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/children-having-fun-balancing-on-tree-389052964">Monkey Business Images/Shutterstock</a></span>
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<p>We see this in our data. For people with COVID who were hospitalised, the point at which a diagnosis of seizures or epilepsy was most common was at nine days after infection. For those who were not hospitalised, the peak was at 41 days. </p>
<p>In children with COVID, the peak point for seizures or epilepsy was at 50 days after infection and at that time children who had COVID were three times more likely to have epilepsy or seizures than children who had flu.</p>
<p>It’s possible that seizures occur due to changes in the immune system which may take some weeks to manifest, thereby contributing to this delay. But we don’t know why seizures might happen after COVID, nor why their onset appears to be delayed after an infection in children and patients with less severe disease.</p>
<p>Most people who have a stroke while infected with COVID will be hospitalised. So it doesn’t seem that stroke is the explanation for the relative increase in post-COVID seizures seen in adults, given we saw an increase among non-hospitalised patients too.</p>
<h2>What now?</h2>
<p>Although the overall rate of seizures and epilepsy after COVID is small, given the large number of people who have been infected with COVID, this could result in increases in the number of people with seizures and epilepsy.</p>
<p>Our study also demonstrates that even relatively milder COVID infections can be associated with neurological conditions, and shows the need for vaccination programmes that try to prevent COVID infection, perhaps especially in children. </p>
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Read more:
<a href="https://theconversation.com/we-studied-how-covid-affects-mental-health-and-brain-disorders-up-to-two-years-after-infection-heres-what-we-found-188918">We studied how COVID affects mental health and brain disorders up to two years after infection – here's what we found</a>
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<p>There are some limitations to this study. For example, we didn’t know which variant of COVID people were infected with or whether they had been vaccinated.</p>
<p>We now need to do more research to try and understand why people may be developing epilepsy and having seizures following COVID. It will also be vital to continue to pool data on the neurological consequences of COVID and track longer-term trajectories of people who do develop seizures following a COVID infection.</p><img src="https://counter.theconversation.com/content/194767/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This study was supported by the National Institute for Health and Care Research (NIHR) Oxford Health Biomedical Research Centre (BRC), grant BRC-1215-20005</span></em></p>People who had COVID were 55% more likely to develop epilepsy or seizures over the next six months than people who had influenza – but the overall risk is still small.Arjune Sen, Head of the Oxford Epilepsy Research Group, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1919232022-10-11T13:58:54Z2022-10-11T13:58:54ZParkinson’s disease: treatment is best started early<p>BBC broadcaster Jeremy Paxman was brought to hospital after he collapsed in a park while walking his dog. A doctor in the emergency department <a href="https://www.itv.com/news/2022-10-03/jeremy-paxmans-doctor-noticed-presenters-parkinsons-on-university-challenge">said to Paxman</a>: “I think you have Parkinson’s.”</p>
<p>The doctor had noticed that Paxman was less animated than usual when presenting University Challenge. A mask-like face is a classic symptom of the disease. </p>
<p>Paxman said the diagnosis was “completely out of the blue”.</p>
<p>In Parkinson’s disease, there is a loss of a chemical in the brain called dopamine that causes movements to be smaller and slower. In the early stages of the disease, people notice that their walking slows and they have difficulty keeping pace with companions. </p>
<p>Sometimes people find it difficult to turn over in bed or have trouble with more awkward tasks, such as doing up buttons. Balance and stability can also be affected, which can put people with the condition at higher risk of falls – as happened to Paxman.</p>
<p>A diagnosis is primarily made through listening to the symptoms that someone describes. Doctors also conduct bedside tests that look for slow and small movements of the hands, arms and legs as well as shaking and stiffness of the muscles. Imaging scans can play a role in helping exclude other causes of movement difficulties. It is important to exclude the changes in movement being caused by some medications or by hardening of the arteries of the brain that happen as people get older. </p>
<p>Early signs of the condition may be present up to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3335740/">20 years before the first movement symptoms occur</a>. Loss of smell, <a href="https://www.michaeljfox.org/acting-out-dreams-while-asleep">acting out dreams while asleep</a> (such as punching, kicking or yelling), feeling low and constipation are all clues that, in combination, might suggest that someone may be at more risk of developing the disease. </p>
<p>Although a loss of dopamine is the key culprit in Parkinson’s, significant advances in understanding the condition have highlighted the importance of other changes in the brain that affect other brain chemicals (neurotransmitters) which cause symptoms that are unrelated to movements. These so-called “non-motor features” affect sleep, memory, thinking, mood, blood pressure, and bladder and bowel function. These changes can be more challenging for people with Parkinson’s than the more visible problems with movement.</p>
<p>Some of the largest Parkinson’s drugs trials running in the UK now target these troubling non-movement related symptoms. These clinical trials test medications for <a href="https://www.ucl.ac.uk/psychiatry/research/mental-health-older-people/top-hat">hallucinations</a>, <a href="https://chiefpd.blogs.bristol.ac.uk/">falls</a> and <a href="https://www.ucl.ac.uk/comprehensive-clinical-trials-unit/research-projects/2022/aug/adept-pd">depression</a>.</p>
<h2>Treatment should be tailored</h2>
<p>The saying: “If you’ve met one person with Parkinson’s, you’ve met one person with Parkinson’s” reflects the fact that the condition affects people very differently. This means that treatments need to be carefully targeted to an individual. A one-size-fits-all approach to care means that people are given the same treatments regardless of their circumstance. This approach, while often applied, fails to take into account a person’s experience of the disease, their unique needs and the goals they want to achieve. As a result care is often fragmented and unsatisfactory. </p>
<p>Being diagnosed with Parkinson’s can cause understandable worry and uncertainty about the future. However, there are many effective drug treatments. Care is often supported by occupational therapists, physiotherapists and nurse specialists who can help people live fulfilling lives. </p>
<p>Most people with Parkinson’s will be offered levodopa – a drug that increases dopamine in the brain. But other drugs that help with movement problems are available, too. They are usually available in pill form or as a patch.</p>
<p>Until around ten years ago, treatment was often delayed until people became very disabled. Treatment is now started promptly to maintain people’s wellbeing and independence. </p>
<p>In later stages of the condition, devices can be fitted that allow medicines to be injected under the skin. Medication can be infused into the intestine through medical pumps or electricity can be used to stimulate affected areas of the brain using deep brain stimulation devices (like a pacemaker for the brain). These treatments are not commonplace but are predominantly used for people with later stages of disease. </p>
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<img alt="Parkinson's Disease patient displaying a surgically installed tube that delivers anti-Parkinson's medication directly into the jejunum" src="https://images.theconversation.com/files/488995/original/file-20221010-18-ye2z3l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488995/original/file-20221010-18-ye2z3l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488995/original/file-20221010-18-ye2z3l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488995/original/file-20221010-18-ye2z3l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488995/original/file-20221010-18-ye2z3l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488995/original/file-20221010-18-ye2z3l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488995/original/file-20221010-18-ye2z3l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Drugs to treat Parkinson’s disease can be delivered straight to the gut.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/genuine-parkinsons-disease-patient-displaying-surgically-1640766406">GerryP/Shutterstock</a></span>
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<p>Although there is currently no cure for Parkinson’s disease, researchers continue to work on finding a cure for the disease or treatment that slows progression. There are exciting developments on the horizon, including early disease detection based on changes in <a href="https://www.manchester.ac.uk/discover/news/parkinsons-breakthrough-can-diagnose-disease-from-skin-swabs-in-3-minutes/">body odour</a>. </p>
<p>Science is progressing rapidly and the prompt recognition and treatment of the condition can mean that people can access an ever-increasing range of effective treatments.</p><img src="https://counter.theconversation.com/content/191923/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emily Henderson receives funding from the National Institute of Health Research UK, Elizabeth Blackwell Institute, Engineering and Physical Sciences Research Council (EPSRC), Alzheimer’s UK, British Geriatrics Society and The Gatsby Foundation. I have consulted and / or received financial support from Kyowa Kirin, Abbvie, Luye, Medicys and Bial.
</span></em></p>Clues that a person is at risk of developing Parkinson’s disease can start 20 years before movement problems begin.Emily Henderson, Associate Professor, Ageing and Movement Disorders, University of BristolLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1844122022-09-09T12:34:01Z2022-09-09T12:34:01ZLa Crosse virus is the second-most common virus in the US spread by mosquitoes – and can cause severe neurological damage in rare cases<figure><img src="https://images.theconversation.com/files/481864/original/file-20220830-19040-p60irc.jpg?ixlib=rb-1.1.0&rect=22%2C45%2C4998%2C3229&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">People catch La Crosse disease primarily from the bite of the eastern tree-hole mosquito – although two other species may also carry the virus.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/mosquito-sucking-blood-on-human-skin-royalty-free-image/1218518415?adppopup=true">Nipol Plobmuang/EyeEm via Getty Images</a></span></figcaption></figure><p>For the Laudick family of Greensburg, Indiana, life forever changed on Aug. 5, 2013. That was the day 4-year-old Leah Laudick told her mom, Shelly, that she had a bad headache. </p>
<p>Two days later, Leah was hospitalized nearby with worsening headaches and a slightly elevated white blood cell count. She slept for most of the day and by Aug. 9 was largely unresponsive. </p>
<p>That day, during her transfer to Peyton Manning Children’s Hospital in Indianapolis, Leah had her first of several seizures. Doctors were unable to identify her illness – tests for diseases like meningitis, Rocky Mountain spotted fever and herpes simplex all came back negative. </p>
<p>One day later, on Aug. 10, Leah’s brain activity stopped. That evening she passed away in the arms of her grieving parents. </p>
<p>A few months later, the Laudicks learned from the Centers for Disease Control and Prevention that an illness called La Crosse disease, contracted from the bite of a mosquito, had caused Leah’s death. </p>
<p>I am <a href="https://epp.tennessee.edu/directory/dr-rebecca-trout-fryxell/">an entomologist</a> at the University of Tennessee who studies how La Crosse disease spreads in the environment. I met the Laudicks – they have given me permission to tell their story – when Leah’s father, Andy, emailed me asking how he could help with my work. Such emails from parents of La Crosse-infected children are why I continue to study the virus. </p>
<p>Together with other <a href="https://www.mdpi.com/2075-4450/13/2/164">researchers at the University of Tennessee</a> and Western Carolina University, I’m working to provide people and communities with effective solutions to preventing this illness. Through my research and <a href="https://www.megabitess.org/">community engagement activities</a>, I am helping to increase awareness of what La Crosse virus is and how people catch it – and can avoid catching it. </p>
<h2>What is La Crosse disease?</h2>
<p><a href="https://www.cdc.gov/lac/index.html">La Crosse disease</a> is the nation’s <a href="https://doi.org/10.15585%2Fmmwr.mm7032a1">second-most prevalent mosquito-borne virus</a>. According to the CDC, West Nile virus makes up <a href="https://www.cdc.gov/mmwr/volumes/68/wr/mm6831a1.htm">more than 90% of annual viral infections</a> from mosquito or tick bites, with <a href="https://www.cdc.gov/mmwr/volumes/68/wr/mm6831a1.htm">La Crosse the next-most prevalent</a> at about 2% of mosquito or tickborne viral infections a year – <a href="https://www.cdc.gov/lac/statistics/index.html">or 50 to 150 cases a year</a>. Both children and adults can be infected with La Crosse virus.</p>
<p>La Crosse was first identified in the U.S. in 1960, and historically, most cases have occurred in <a href="https://doi.org/10.1371/journal.pone.0006145">Upper Midwest</a> and Mid-Atlantic states. Leah’s case was the only one reported in Indiana in 2013. </p>
<p>The majority now occur in the southern Appalachia region, which stretches from northern Alabama and Georgia, across eastern Tennessee and western North Carolina, and north to parts of Kentucky, Virginia and West Virginia. We still do not know why this is the case, but there are <a href="https://doi.org/10.1007/s10393-012-0773-7">many hypotheses</a> centered around climate, land use and invasive mosquito species.</p>
<p><iframe id="2m3d9" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/2m3d9/2/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<h2>How do people catch La Crosse?</h2>
<p>La Crosse virus is carried and transmitted primarily <a href="https://wrbu.si.edu/vectorspecies/mosquitoes/triseriatus">by the eastern tree-hole mosquito</a>, <em>Aedes triseriatus</em>, a native species found throughout most of the Eastern U.S. This mosquito’s preferred habitat is places with obvious tree holes <a href="https://wrbu.si.edu/vectorspecies/mosquitoes/triseriatus">for female mosquitoes to deposit their eggs</a>, such as hardwood forests.</p>
<p>However, the virus <a href="https://doi.org/10.2987/moco-31-03-233-241.1">may also be transmitted</a> – although not as well – by two exotic and invasive mosquito species: the <a href="https://www.wrbu.si.edu/vectorspecies/mosquitoes/albopictus">tiger mosquito</a>, <em>Aedes albopictus,</em> and <a href="https://www.wrbu.si.edu/index.php/vectorspecies/mosquitoes/japonicus">the bush mosquito</a>, <em>Aedes japonicus.</em></p>
<p>Tiger and bush mosquitoes are spreading throughout the U.S. in response to changes in landscape and climate, and also by hitchhiking inside water-filled containers. Our team has <a href="https://doi.org/10.1371/journal.pone.0237322">found them</a> together in the same habitats as eastern tree-hole mosquitoes, in places with hardwood trees like parks, cemeteries and residential backyards. Our team has also found these mosquitoes in <a href="https://doi.org/10.1371/journal.pone.0237322">close proximity</a> to confirmed La Crosse cases.</p>
<p>All three mosquito species develop in the same water sources and feed on mammals, including humans. Some <a href="https://doi.org/10.1007/s10393-012-0773-7">scientists speculate that</a> these factors have been key to the distribution of La Crosse in the Appalachian region, although there is still a lot to learn about these mosquito species and their role in spreading the virus.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/483611/original/file-20220908-9281-7nbj62.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up photo of the eastern treehole mosquito." src="https://images.theconversation.com/files/483611/original/file-20220908-9281-7nbj62.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/483611/original/file-20220908-9281-7nbj62.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/483611/original/file-20220908-9281-7nbj62.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/483611/original/file-20220908-9281-7nbj62.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/483611/original/file-20220908-9281-7nbj62.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/483611/original/file-20220908-9281-7nbj62.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/483611/original/file-20220908-9281-7nbj62.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The eastern tree-hole mosquito is the primary carrier of La Crosse virus.</span>
<span class="attribution"><span class="source">Dave Paulsen, Department of Entomology and Plant Pathology, University of Tennessee</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
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</figure>
<h2>Diagnosing La Crosse is difficult</h2>
<p>La Crosse disease is easy to misdiagnose, in part because its symptoms can be easily confused with those of other illnesses, such as the flu. Moreover, the only way to test for La Crosse involves <a href="https://www.cdc.gov/lac/healthcare-providers/diagnostic-testing.html">sending samples of blood and cerebrospinal fluid</a> to the CDC.</p>
<p>However, La Crosse infections <a href="https://doi.org/10.1371/journal.pone.0006954">tend to cluster in local communities</a> from year to year. For example, of the 115 cases reported in Tennessee since 2011, <a href="https://www.tn.gov/health/cedep/vector-borne-diseases/mosquito-borne-diseases/mosquito-borne-diseases-of-concern/la-crosse-encephalitis.html">most occurred in less than 20%</a> of the state’s 95 counties. So even a few successfully diagnosed cases can tip off local doctors and officials that the disease is present in their area. </p>
<h2>Symptoms of La Crosse</h2>
<p>Symptomatic cases of La Crosse begin with a mild illness involving fever, fatigue, vomiting and headache. This lasts for nearly two weeks. Most infected individuals recover fully.</p>
<p>However, like West Nile, La Crosse disease is “neuroinvasive,” meaning it can invade and affect the central nervous system.</p>
<p><a href="https://doi.org/10.1186/s12974-021-02173-4">Research suggests that age</a>, the <a href="https://doi.org/10.1186/s12974-017-0836-3">development of the immune system</a> and the <a href="https://doi.org/10.3201%2Feid2105.141992">strain of the virus</a> are key factors in whether someone develops neuroinvasive La Crosse, while delays in seeking medical help <a href="https://doi.org/10.1056/NEJM200103153441103">also influence its severity</a>. The most susceptible are immunocompromised individuals and children – more than 60 children a year are diagnosed with neuroinvasive La Crosse. </p>
<p>Severe cases <a href="https://doi.org/10.1542/hpeds.2012-0022">are usually discovered in the hospital</a> after the patient experiences a seizure, coma, partial paralysis of one side or altered mental state. </p>
<p>Severe La Crosse can result in <a href="https://doi.org/10.1093/cid/ciac403">long-term neurological damage</a>. Deaths caused by infection are rare, but neurological and behavioral effects can occur after infection, including cognitive disorders, diagnoses of attention-deficit/hyperactivity disorder and <a href="https://doi.org/10.1212/WNL.18.10.1023">reduced IQ scores</a>.</p>
<h2>Can La Crosse disease be prevented?</h2>
<p>Until the scientific community understands more about the ecology and epidemiology of La Crosse, my colleagues and I will continue to recommend preventing the mosquito bite in the first place to avoid infections.</p>
<p>One tactic is to reduce local opportunities for the mosquitoes that carry La Crosse to breed. This includes getting rid of objects outdoors that can catch and contain water – like empty plant pots, cans or toys – because these <a href="https://doi.org/10.52707/1081-1710-46.1.34">can emulate the conditions of a mosquito-friendly forest</a>. Mosquitoes carrying La Crosse virus are also found developing in tires containing water, so it’s a good idea <a href="https://doi.org/10.1093/jmedent/35.4.573">to drill drainage holes in tire swings</a>.</p>
<figure class="align-center ">
<img alt="Researcher crouching near the ground at sunny spot within a forest." src="https://images.theconversation.com/files/483330/original/file-20220907-9232-jgyaex.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/483330/original/file-20220907-9232-jgyaex.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=437&fit=crop&dpr=1 600w, https://images.theconversation.com/files/483330/original/file-20220907-9232-jgyaex.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=437&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/483330/original/file-20220907-9232-jgyaex.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=437&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/483330/original/file-20220907-9232-jgyaex.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=549&fit=crop&dpr=1 754w, https://images.theconversation.com/files/483330/original/file-20220907-9232-jgyaex.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=549&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/483330/original/file-20220907-9232-jgyaex.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=549&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Rebecca Trout Fryxell looks for mosquitoes in a puddle created by an above-ground tree root.</span>
<span class="attribution"><span class="source">Trout Fryxell’s Medical and Veterinary Entomology Laboratory, Univ. of Tennessee</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Another strategy is to try to avoid mosquitoes, perhaps by staying inside during peak mosquito hours, which are typically in the <a href="https://doi.org/10.2987/16-6620R.1">early evening</a>.</p>
<p>Using area repellents such as mosquito coils, wearing light-colored clothing and applying mosquito repellent can also help prevent bites. </p>
<p>The Environmental Protection Agency’s <a href="https://www.epa.gov/insect-repellents/find-repellent-right-you">guide to the active ingredients in insect repellents</a> describes which are most effective at repelling mosquitoes and how many hours they last. Like sunscreen, insect repellents may need to be reapplied while spending time outdoors. </p>
<p>Leah Laudick adored her six siblings and “enjoyed collecting rocks, chasing butterflies and picking flowers for her mom,” in the words of her father. </p>
<p>As officials and the public learn more about La Crosse, both avoiding and diagnosing the infection could become easier, and more lives like Leah’s could be saved.</p><img src="https://counter.theconversation.com/content/184412/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rebecca Trout Fryxell receives funding from the United States Department of Agriculture. </span></em></p>Not all cases of La Crosse disease affect the neurological system, but those that do can be severe and sometimes fatal – especially in children.Rebecca Trout Fryxell, Associate Professor of Medical and Veterinary Entomology, University of TennesseeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1824912022-07-06T12:19:47Z2022-07-06T12:19:47ZBrain stimulation can rewire and heal damaged neural connections, but it isn’t clear how – research suggests personalization may be key to more effective therapies<figure><img src="https://images.theconversation.com/files/472114/original/file-20220701-16-9uirtd.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2000%2C1500&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Advances in artificial intelligence and technology have allowed researchers to better explore the mechanisms behind neurostimulation.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/concept-of-the-diversity-of-peoples-talents-royalty-free-illustration/1323880880">Iryna Spodarenko/iStock via Getty Images</a></span></figcaption></figure><p>The connections between the neurons in your brain enable you to do amazing things, from brushing your teeth to solving calculus equations. When these connections become damaged, often as a result of conditions like stroke or traumatic brain injury, these abilities can be lost. Directly activating neurons with tiny pulses of electricity, however, can help <a href="https://doi.org/10.1038/nature05226">rewire these connections</a> and potentially restore function.</p>
<p>Doctors currently use this technique, called neurostimulation, to treat conditions like <a href="https://www.parkinson.org/Understanding-Parkinsons/Treatment/Surgical-Treatment-Options/Deep-Brain-Stimulation">Parkinson’s</a> and <a href="https://theconversation.com/neurostimulation-may-herald-a-new-treatment-for-depression-141958">depression</a>. We believe that neurostimulation has the potential to not only treat symptoms but also cure a wider range of diseases by repairing damaged connections. However, it has been unclear how to best fine-tune stimulation to specifically target damaged connections within the brain.</p>
<p>New forms of neurotechnology and statistical modeling that have developed over the past few years have made answering this question possible. Our team of <a href="https://scholar.google.com/citations?hl=en&user=HX4Te8AAAAAJ">biomedical</a> <a href="https://scholar.google.com/citations?user=mF4d4nEAAAAJ&hl=en">engineers</a> and <a href="https://scholar.google.com/citations?user=rqeYxosAAAAJ&hl=en">statisticians</a> used these tools to show that the changes neurostimulation makes to neurons depend on how they were connected in the first place. In other words, for neurostimulation to work, it needs to be <a href="https://doi.org/10.1016/j.isci.2022.104285">tailored to each individual’s brain</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/tgKIbdTWq7o?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Deep-brain stimulation is one form of neurostimulation currently used to treat Parkinson’s and depression.</span></figcaption>
</figure>
<h2>New technologies shine a light on stimulation</h2>
<p>To investigate what factors most strongly influence the effects of neurostimulation, we stimulated the brains of two monkeys and recorded how the connections between different regions changed. We focused on brain regions involved in motor movement and sensory processing – areas that are often impaired in neurological disorders like stroke.</p>
<p>We recorded our data with a large-scale <a href="https://doi.org/10.1016/j.neuron.2016.01.013">neural interface</a> – a device that rests directly on the surface of a live brain and records the activity of the neurons below it. Our neural interface was able to precisely stimulate each area through <a href="https://doi.org/10.1016/j.neuron.2011.06.004">optogenetics</a>, a technique that shines a light on genetically modified neurons to activate them. While not yet approved for use in people, optogenetics has unique advantages over other forms of neurostimulation that make it especially useful for understanding how stimulation affects the brain. This includes its ability to make higher-quality recording of the electrical signals generated by the brain.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/I64X7vHSHOE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Optogenetics allows researchers to precisely control the behavior of specific neurons and other cells.</span></figcaption>
</figure>
<p>We then analyzed our data with an <a href="https://doi.org/10.48550/arXiv.1611.09972">artificial intelligence algorithm</a> designed to predict how preexisting brain connections and different stimulation parameters will affect the brain.</p>
<p>This algorithm is similar to other AI techniques like <a href="https://www.techtarget.com/searchenterpriseai/definition/deep-learning-deep-neural-network">deep learning</a> that find complex relationships in data that are otherwise difficult or impossible to identify. But unlike these “black box” models that make it impossible for researchers to understand how they arrived at their findings, our technique allows us to see why and how it makes its predictions. Using this algorithm, we were able to test different factors that influence connection changes and visualize how they each contributed to the overall prediction the model provided. These factors included pauses between stimulation sessions, the distance between stimulation locations in the brain and the region of the brain in which the electrodes were placed, among others.</p>
<p>We found that it was the existing connections in the brain, not how the stimulation was delivered, that was the most important factor to predicting changes in the brain. What this suggests is that the unique qualities of each individual’s brain are crucial to understand how it will respond to stimulation, pointing to a need for treatment personalization to maximize its benefits. This could look like tailoring the strength, frequency and location of the neurostimulation to each person’s brain.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/bApsqEgAfwI?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Targeted stimulation could help rewire damaged connections in the brain.</span></figcaption>
</figure>
<h2>Why personalization matters</h2>
<p>Brain stimulation has the potential to treat a wide range of neurological diseases. Our work suggests that studying how existing brain connectivity affects neurostimulation response may be a new direction worth further investigation. We believe that changing neural connections themselves for long-term effects, as opposed to stimulating neurons for short-term changes in neural activity, may help move treatments from just treating symptoms to curing diseases outright.</p>
<p>One health condition for which personalization could lead to improved brain stimulation therapies is stroke, one of the <a href="https://www.heart.org/en/news/2018/05/01/stroke-falls-to-no-5-killer-in-us">leading causes</a> of serious long-term disability and death in the U.S. While the brain is able to partially repair the damage caused by stroke, it has only a <a href="https://doi.org/10.1177%2F1545968321992330">two-week window</a> to do this before the chances of recovery significantly drop off. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/472116/original/file-20220701-18-jgd8r3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Doctor placing transcranial magnetic stimulation device on patient's head." src="https://images.theconversation.com/files/472116/original/file-20220701-18-jgd8r3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/472116/original/file-20220701-18-jgd8r3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/472116/original/file-20220701-18-jgd8r3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/472116/original/file-20220701-18-jgd8r3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/472116/original/file-20220701-18-jgd8r3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/472116/original/file-20220701-18-jgd8r3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/472116/original/file-20220701-18-jgd8r3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Personalizing brain stimulation may lead to more effective treatments for a broader range of conditions.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/patient-jerry-peppe-undergoes-transcranial-magnetic-news-photo/847395736">Suzanne Kreiter/The Boston Globe via Getty Images</a></span>
</figcaption>
</figure>
<p>A failed 2008 clinical study one of us was involved with, the <a href="https://doi.org/10.1177/1545968308317532">Everest trial</a>, explored the possibility of using brain stimulation to extend this recovery period and help stroke survivors regain their ability to move. Based on our recent study, we hypothesize that the clinical trial may have failed because researchers applied the same generic stimulation to all patients instead of tailoring it to each individual brain. Applying the same brain stimulation parameters may have worked in <a href="https://doi.org/10.1179/016164103771953871">rodent</a> <a href="https://doi.org/10.1179/016164103771953871">studies</a>, but human brains are much more complex. While we can’t know for sure if this is the reason the clinical trial failed, our research suggests that stimulation may have needed to be much more personalized to be effective.</p>
<h2>Next steps to personalizing brain stimulation</h2>
<p>Our work shows that tailoring treatment to each individual brain could help improve brain stimulation outcomes, and puts forward tools to study how neural connectivity influences stimulation. But further research is needed to figure out how personalization would best be done by precisely strengthening or weakening specific neural connections.</p>
<p>It is also worth noting that we have tested our technique on only two brain regions thus far. We plan on replicating this study in other brain regions to verify that our findings can be generalized across the brain as a whole and are applicable to different neurological and psychiatric disorders. We are also in the process of using our neural interface and AI algorithm to design stimulation patterns that can induce specific changes in the brain to repair dysfunctional connections.</p>
<p>The full potential of brain stimulation will not be realized until scientists have a better understanding of how it affects the brain. We believe that figuring out how existing patterns of brain connectivity interact and change with stimulation could open doors to more treatments and therapies for neurological and psychiatric diseases.</p><img src="https://counter.theconversation.com/content/182491/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Azadeh Yazdan-Shahmorad receives funding from the National Institute of Health, the American Heart Association, the Washington Research Foundation and the Weill Neurohub. In addition to the above, she has received funding from the National Science Foundation, the University of Washington Royalty Research Funds and DARPA in the past.</span></em></p><p class="fine-print"><em><span>Alec Greaves-Tunnell currently works as an applied scientist at Amazon Web Services.</span></em></p><p class="fine-print"><em><span>Julien Bloch receives funding from the National Institutes of Health and has previously received funding from the National Science Foundation. </span></em></p>Existing brain connections may influence the effectiveness of neurostimulation. Tailoring treatments to each individual brain could expand the number of conditions brain stimulation can treat.Azadeh Yazdan-Shahmorad, Assistant Professor of Bioengineering, and Electrical and Computer Engineering, University of WashingtonAlec Greaves-Tunnell, Visiting Researcher in Computational Neuroscience, University of WashingtonJulien Bloch, PhD Candidate in Neural Engineering, University of WashingtonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1707962021-12-17T13:26:16Z2021-12-17T13:26:16ZThe ‘runner’s high’ may result from molecules called cannabinoids – the body’s own version of THC and CBD<figure><img src="https://images.theconversation.com/files/436228/original/file-20211207-172173-y26qwj.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5220%2C3453&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Exercise spurs the release of the body's natural cannabinoids, which have myriad benefits for mental health and stress relief.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/running-along-road-at-sunrise-in-iceland-royalty-free-image/578633163?adppopup=true">Luca Sage/Stone via Getty Images</a></span></figcaption></figure><p>Many people have experienced reductions in stress, pain and anxiety and sometimes even euphoria after exercise. What’s behind this so-called “runner’s high”? New research on the neuroscience of exercise may surprise you. </p>
<p>The “runner’s high” has long been attributed to <a href="https://doi.org/10.2519/jospt.1983.4.3.169">endorphins</a>. These are chemicals produced naturally in the body of humans and other animals after exercise and in response to pain or stress. </p>
<p>However, <a href="https://doi.org/10.1089/can.2021.0113">new research from my lab</a> summarizes nearly two decades of work on this topic. We found that exercise reliably increases levels of the body’s endocannabinoids – which are molecules that work to maintain balance in the brain and body – a process called “homeostasis.” This natural chemical boost may better explain some of the beneficial effects of exercise on brain and body. </p>
<p>I am a <a href="https://scholar.google.com/citations?user=S9ykvZUAAAAJ&hl=en">neuroscientist</a> at the Wayne State University School of Medicine. <a href="https://wsuthinklab.mystrikingly.com/">My lab</a> studies brain development and mental health, as well as the role of the endocannabinoid system in stress regulation and anxiety disorders in children and adolescents. </p>
<p>This research has implications for everyone who exercises with the aim of reducing stress and should serve as a motivator for those who don’t regularly exercise. </p>
<h2>Health benefits of exercise</h2>
<p><a href="https://doi.org/10.1097/HCO.0000000000000437">Several decades of research</a> has shown that exercise is beneficial for physical health. These studies find a consistent link between varying amounts of physical activity and reduced risk of <a href="http://dx.doi.org/10.1136/bjsports-2018-100393">premature death</a> and dozens of chronic health conditions, including <a href="https://doi.org/10.1007/s10654-015-0056-z">diabetes</a>, <a href="https://doi.org/10.1007/s40279-013-0065-6">hypertension</a>, <a href="https://doi.org/10.1016/j.jval.2018.06.020">cancer</a> and <a href="https://doi.org/10.3390/ijerph9020391">heart disease</a>.</p>
<figure class="align-center ">
<img alt="The marijuana plant cannabis." src="https://images.theconversation.com/files/436203/original/file-20211207-19-7n3tp8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/436203/original/file-20211207-19-7n3tp8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/436203/original/file-20211207-19-7n3tp8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/436203/original/file-20211207-19-7n3tp8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/436203/original/file-20211207-19-7n3tp8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/436203/original/file-20211207-19-7n3tp8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/436203/original/file-20211207-19-7n3tp8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">While cannabinoids are produced in cannabis, the marijuana plant, they are also made in the human body.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/background-texture-of-marijuana-plants-outdoor-royalty-free-image/1258024915?adppopup=true">Iuliia Bondar/Moment via Getty Images</a></span>
</figcaption>
</figure>
<p>More recently – over about the past <a href="https://doi.org/10.3389/fpsyt.2014.00066">two decades</a> – mounting research shows that exercise is also <a href="https://theconversation.com/swimming-gives-your-brain-a-boost-but-scientists-dont-know-yet-why-its-better-than-other-aerobic-activities-164297">highly beneficial for mental health</a>. In fact, regular exercise is associated with lower symptoms of anxiety, depression, Parkinson’s disease and other common mental health or <a href="https://doi.org/10.1159/000223730">neurological problems</a>. Consistent exercise <a href="https://doi.org/10.1159/000350946">is also linked to</a> better cognitive performance, improved mood, lower stress and higher self-esteem. </p>
<p>It is not yet clear what is behind these mental health boosts. We do know that exercise has a variety of effects on the brain, including raising <a href="https://doi.org/10.1038/tp.2017.135">metabolism</a> and <a href="https://doi.org/10.3233/JAD-201456">blood flow</a>, promoting the formation of <a href="https://doi.org/10.3389/fnins.2018.00052">new brain cells</a> – a process called neurogenesis – and increasing the release of several chemicals in the brain. </p>
<p>Some of these chemicals are called neurotrophic factors, such as <a href="https://doi.org/10.1159/000223730">brain-derived neurotrophic factor</a>. BDNF is intricately involved in brain “plasticity,” or changes in activity of brain cells, including those related to <a href="https://doi.org/10.3389/fncel.2019.00363">learning and memory</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/lk3mrNqhn24?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">From the Dana Foundation: “How Exercise Affects The Brain”</span></figcaption>
</figure>
<p>Scientists have also shown that exercise increases blood levels of endorphins, one of the body’s natural opioids. Opioids are chemicals that work in the brain and have a variety of effects, including <a href="https://doi.org/10.3389/fpain.2021.721357">helping to relieve pain</a>. Some <a href="https://doi.org/10.1093/cercor/bhn013">early research</a> in the 1980s contributed to the long-standing popular belief that this endorphin release is related to the euphoric feeling known as the runner’s high. </p>
<p>However, <a href="http://dx.doi.org/10.1136/bjsm.2004.011718">scientists have</a> <a href="https://doi.org/10.1073/pnas.1514996112">long questioned</a> the role of endorphins in the runner’s high sensation, in part because endorphins cannot cross into the brain through the <a href="https://doi.org/10.1101/cshperspect.a020412">blood-brain barrier</a>, which protects the brain from toxins and pathogens. So endorphins are not likely to be the main driver for the beneficial effects of exercise on mood and mental state.</p>
<p>This is where our research and <a href="http://dx.doi.org/10.1136/bjsm.2004.011718">that of others</a> points to the role of our body’s natural versions of cannabinoids, called endocannabinoids.</p>
<h2>The surprising role of endocannabinoids</h2>
<p>You <a href="https://www.healthline.com/health/cbd-vs-thc">may be familiar with</a> cannabinoids such as tetrahydrocannabinol – better known as THC – the psychoactive compound in cannabis (from the <em>Cannabis sativa L.</em> plant) that causes people to feel high. Or you may have heard of <a href="https://www.fda.gov/consumers/consumer-updates/what-you-need-know-and-what-were-working-find-out-about-products-containing-cannabis-or-cannabis">cannabidiol, commonly known as CBD, an extract of cannabis</a> that is infused in some foods, medicines, oils and many other products. </p>
<p>But many people do not realize that humans also create their own versions of these chemicals, called endocannabinoids. These are tiny molecules made of lipids – or fats – that circulate in the brain and body; “endo” refers to those produced in the body rather than from a plant or in a lab.</p>
<p>Endocannabinoids work on cannabinoid receptors <a href="https://doi.org/10.1073/pnas.0703472104">throughout the brain</a> and body. They cause a variety of effects, including pain relief, reduction of anxiety and stress and enhanced learning and memory. They also affect hunger, inflammation and <a href="https://dx.doi.org/10.1038%2Fnpp.2017.130">immune functioning</a>. Endocannabinoid levels can be influenced by food, time of day, exercise, obesity, injury, inflammation and stress. </p>
<p>It’s worth noting that one should not be tempted to forgo a run or bike ride and resort to smoking or ingesting cannabis instead. Endocannabinoids lack the unwanted effects that come with getting high, such as <a href="https://doi.org/10.1007/s00213-006-0508-y">mental impairment</a>.</p>
<h2>Understanding the runner’s high</h2>
<p>Studies <a href="https://doi.org/10.1016/j.psyneuen.2021.105173">in humans</a> and in <a href="https://doi.org/10.1073/pnas.1514996112">animal models</a> are pointing to endocannabinoids – not endorphins – as the star players in the runner’s high.</p>
<p>These elegant studies demonstrate that when opioid receptors are blocked – in <a href="https://doi.org/10.1016/j.psyneuen.2021.105173">one example</a> by a drug called naltrexone – people still experienced euphoria and reduced pain and anxiety after exercise. On the flip side, the studies showed that blocking the effects of cannabinoid receptors reduced the beneficial effects of exercise on euphoria, pain and anxiety. </p>
<p>While <a href="https://doi.org/10.1016/j.mhpa.2020.100366">several studies</a> <a href="https://doi.org/10.1007/s00421-012-2495-5">have shown</a> that exercise increases the levels of endocannabinoids circulating in the blood, some have reported inconsistent findings, or that different endocannabinoids produce <a href="https://doi.org/10.3389/fnbeh.2018.00269">varying effects</a>. We also don’t know yet if all types of exercise, such as cycling, running or resistance exercise like weightlifting, produce similar results. And it is an open question whether people with and without preexisting health conditions like depression, PTSD or fibromyalgia experience the same endocannabinoid boosts.</p>
<p>To address these questions, an undergraduate student in my lab, Shreya Desai, led a <a href="https://doi.org/10.1089/can.2021.0113">systematic review and meta-analysis</a> of 33 published studies on the impact of exercise on endocannabinoid levels. We compared the effects of an “acute” exercise session – like going for a 30-minute run or cycle – with the effects of “chronic” programs, such as a 10-week running or weightlifting program. We separated them out because different levels and patterns of exertion could have very distinct effects on endocannabinoid responses.</p>
<p>We found that acute exercise consistently boosted endocannabinoid levels across studies. The effects were most consistent for a chemical messenger known as anandamide – the so-called <a href="https://doi.org/10.1126/science.1470919">“bliss” molecule</a>, which was named, in part, for its positive effects on mood.</p>
<p>Interestingly, we observed this exercise-related boost in endocannabinoids across different types of exercise, including running, swimming and weightlifting, and across individuals with and without preexisting health conditions. Although only a few studies looked at intensity and duration of exercise, it appears that moderate levels of exercise intensity – such as cycling or running – are more effective than lower-intensity exercise – like walking at slow speeds or low incline – when it comes to raising endocannabinoid levels. This suggests that it is important to keep your heart rate elevated – that is, between about 70% and 80% of age-adjusted maximum heart rate – for at least 30 minutes to reap the full benefits. </p>
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<p>There are still a lot of questions about the links between endocannabinoids and beneficial effects from exercise. For example, we didn’t see consistent effects for how a chronic exercise regimen, such as a six-week cycling program, might affect resting endocannabinoid levels. Likewise, it isn’t yet clear what the minimum amount of exercise is to get a boost in endocannabinoids, and how long these compounds remain elevated after acute exercise. </p>
<p>Despite these open questions, these findings bring researchers one step closer to understanding how exercise benefits brain and body. And they offer an important motivator for making time for exercise during the rush of the holidays.</p><img src="https://counter.theconversation.com/content/170796/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dr. Marusak is funded, in part, by the National Institutes of Mental Health (K01MH119241).</span></em></p>A growing body of research points to the body’s natural cannabinoid system as the primary driver behind the runner’s high – and the mental health boost and stress relief following exercise.Hilary A. Marusak, Assistant Professor of Psychiatry and Behavioral Neurosciences, Wayne State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1083192018-12-18T11:48:58Z2018-12-18T11:48:58ZAdvanced digital networks look a lot like the human nervous system<figure><img src="https://images.theconversation.com/files/251002/original/file-20181217-185240-8tynvo.jpg?ixlib=rb-1.1.0&rect=594%2C189%2C4742%2C2888&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Studying digital and biological connections can shed light on both fields.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-illustration/ai-artificial-intelligence-concept-machine-learning-1012126252">MY stock/Shutterstock.com</a></span></figcaption></figure><p>Parents have experienced how newborns grab their finger and hold tight. This almost instantaneous response is one of the sweetest involuntary movements that babies exhibit. The newborn’s nerves sense a touch, process the information and react without having to send a signal to the brain. Though in people this ability fades very early in life, the system that enables it offers a useful example for digital networks connecting sensors, processors and machinery to translate information into action.</p>
<p><a href="https://scholar.google.com/citations?user=7z-nA_kAAAAJ&hl=en">My research</a> on both the human nervous system and advanced telecommunications networks has found some striking parallels between the two, including the similarity between babies’ nervous systems and the rapid-response networks now being developed to handle always-on, always-connected networks of sensors, cameras and microphones throughout <a href="https://theconversation.com/do-i-want-an-always-on-digital-assistant-listening-in-all-the-time-92571">people’s homes</a>, <a href="https://interestingengineering.com/the-technologies-building-the-smart-cities-of-the-future">communities</a> and <a href="https://www.industryweek.com/technology/dawn-smart-factory">workplaces</a>. </p>
<p>These insights can suggest new ways to think about designing future telecommunications systems, as well as provide new ideas for diagnosing and <a href="https://brain.ieee.org/newsletter/2018-issue-3/discovery-of-new-neurological-networks/">treating neurological disorders</a> like multiple sclerosis, autism spectrum disorder and Alzheimer’s disease.</p>
<h2>A view of human neurology</h2>
<p>Generally speaking, the nervous system has three main components: the brain, the spinal cord and the peripheral nervous system. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/251037/original/file-20181217-185240-at9go0.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/251037/original/file-20181217-185240-at9go0.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/251037/original/file-20181217-185240-at9go0.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1109&fit=crop&dpr=1 600w, https://images.theconversation.com/files/251037/original/file-20181217-185240-at9go0.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1109&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/251037/original/file-20181217-185240-at9go0.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1109&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/251037/original/file-20181217-185240-at9go0.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1394&fit=crop&dpr=1 754w, https://images.theconversation.com/files/251037/original/file-20181217-185240-at9go0.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1394&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/251037/original/file-20181217-185240-at9go0.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1394&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The human nervous system can be understood as a network of interconnected sensors and processors.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/121935927@N06/13578831923">Siyavula Education/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>The <a href="https://emedicine.medscape.com/article/1948687-overview">peripheral nervous system</a> is distributed throughout the entire body, sensing inputs like pressure, heat and cold, and conveying that information through the spinal cord to the brain. This system also handles the responses from the brain, controlling voluntary movements, and does some local regulation of involuntary body functions like breathing, digestion and keeping the heart beating.</p>
<p>The <a href="https://www.merckmanuals.com/home/brain,-spinal-cord,-and-nerve-disorders/biology-of-the-nervous-system/spinal-cord">spinal cord</a> handles large numbers of sensory inputs and action responses passing back and forth between the brain and the body. It also handles involuntary muscular movements called <a href="https://www.bbc.com/bitesize/guides/ztjrng8/revision/3">reflex arcs</a>, such as the knee jerk reflex when the doctor performs an examination or the rapid “pull away” of a hand when something hot is touched. </p>
<p>The brain, the center of most of the nervous system’s processing power, has several <a href="https://www.health.harvard.edu/blog/right-brainleft-brain-right-2017082512222">specialized regions</a> in its right and left hemispheres. These areas take input from sensors such as the eyes, ears and skin, and return outputs in the form of thoughts, emotions, memories and movement. In many cases, these outputs <a href="https://www.huffpost.com/entry/how-your-thoughts-change-your-brain-cells-and-genes_b_9516176">are also used by other parts of the brain as inputs that enable</a> refinement and learning.</p>
<p>In healthy people, these elements work together in extraordinary harmony by combining networks of cells that respond to specific chemicals, mechanical changes, light characteristics, temperature changes and pain through a process called <a href="https://www.ncbi.nlm.nih.gov/books/NBK21661/">sensory transduction</a>. This complexity makes even one of the smallest components of the nervous system, the <a href="https://doi.org/10.1016/S0960-9822(06)00203-X">nerve fiber, or axon</a>, a challenge to study. </p>
<p>Some of the nervous system’s interconnections, long thought to only be <a href="http://www.humanconnectomeproject.org/">physical</a>, may also be <a href="http://doi.org/10.5772/intechopen.71945">effectively wireless</a>. The brain generates a <a href="https://doi.org/10.1109/EMBC.2015.7318854">highly specialized electric field</a> at certain nerve fiber sites during the normal course of its operation. Measuring the characteristics of this field can offer indications that a brain is healthy, or that it may have certain neurological disorders.</p>
<h2>Inside telecommunications networks</h2>
<p>The current generation of advanced telecommunications networks, known as <a href="https://theconversation.com/what-is-5g-the-next-generation-of-wireless-explained-96165">5G</a>, is wireless, and has three similar categories of components.</p>
<p>The digital equivalent of the peripheral nervous system is the “internet of things.” It is a vast and growing network of devices, vehicles and home appliances that contain electronics, software and connectivity that let them connect with each other, <a href="https://readwrite.com/2016/06/28/proglove-brings-smart-gloves-to-the-factory-floor-it1/">interacting and exchanging data</a>.</p>
<p>The technological equivalent of the brain is the “<a href="https://www.pcmag.com/article2/0,2817,2372163,00.asp">cloud</a>,” an internet-connected group of powerful computers and processors that store, manage and process data. They often work together to handle complex tasks involving large amounts of input and processing, before delivering outputs back over the internet. </p>
<p>In between those two types of components is the spinal-cord equivalent, a new type of network called a “<a href="https://doi.org/10.1109/JIOT.2016.2584538">fog</a>” – a play on the fact that it’s a thinly distributed cloud – set up to shorten network connections and the resulting processing delays between the cloud and remote devices. The processors and storage devices in the fog can handle tasks that require especially rapid reactions.</p>
<h2>Striking similarities</h2>
<p>In building technological networks throughout the modern world, people have apparently – and likely unconsciously – mirrored human neurology. </p>
<p>This offers opportunities to identify technological solutions to networking problems that could be adapted into medical treatments for neurological disorders that have no known cures. </p>
<p>Autism spectrum disorder, for example, is a serious developmental condition that impairs people’s ability to communicate and interact. It’s believed to occur as a result of an imbalance between <a href="https://knowingneurons.com/2017/01/25/excitation-inhibition/">two types of neural communications</a>: People with autism spectrum disorder have too much activity in neurons that excite other neurons and too little activity in neurons that quiet other neurons down. This is like what happens when some links in a telecommunications networks get overloaded, while others are not busy at all. Software tools that manage large cloud and fog networks can even out demand and minimize telecommunication delays. These programs can also simulate – and suggest ways to reduce – the network imbalances in <a href="http://asdnet.fmhi.usf.edu/faculty/morgera.html">autism-related</a> impairments.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/Jg50wEHqpas?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Salvatore Domenic Morgera explains the network of the nervous system.</span></figcaption>
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<p>Multiple sclerosis is an often disabling disease in which the body’s immune system eats away at nerve fibers’ protective coverings. This disrupts the flow of information within the brain, and between the brain and the body. Technologically, this is similar to outages at particular network connection points, which is regularly dealt with by sending messages by other routes that have working connections. Perhaps medical research can identify ways to reroute nerve messages through nearby links when some nerves aren’t working properly.</p>
<h2>Using software and medicine together</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/251042/original/file-20181217-185268-j6nq7r.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/251042/original/file-20181217-185268-j6nq7r.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/251042/original/file-20181217-185268-j6nq7r.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1000&fit=crop&dpr=1 600w, https://images.theconversation.com/files/251042/original/file-20181217-185268-j6nq7r.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1000&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/251042/original/file-20181217-185268-j6nq7r.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1000&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/251042/original/file-20181217-185268-j6nq7r.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1257&fit=crop&dpr=1 754w, https://images.theconversation.com/files/251042/original/file-20181217-185268-j6nq7r.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1257&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/251042/original/file-20181217-185268-j6nq7r.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1257&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Neural communications break down when affected by Alzheimer’s disease.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Blausen_0017_AlzheimersDisease.png">BruceBlaus/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Alzheimer’s disease is a type of dementia that causes problems with memory, thinking and behavior. In 2015, I presented work by my <a href="https://www.usf.edu/engineering/ee/faculty-staff/index.aspx">research lab</a> on the discovery of <a href="https://www.bmes.org/files/Annual%20Meeting%20Program%20Guides/2015AnnualMeetingProgram.pdf#page=191">new networks in the brain</a> whose behavior indicated that Alzheimer’s disease might be an autoimmune disease, like MS is. This suggests a brain with Alzheimer’s could be like a telecommunications network being attacked by an intruder changing not just data within the network, but also the network’s structure itself.</p>
<p>My research group then used the <a href="https://doi.org/10.1109/ACCESS.2018.2866962">human immune system as inspiration</a> for <a href="https://doi.org/10.1109/SURV.2013.050113.00191">developing software to defend computer networks</a> against malicious attacks. This software can, in turn, be used to simulate the progress of Alzheimer’s disease in a patient, perhaps highlighting ways to reduce its effects.</p>
<p>The nervous system’s involvement in other autoimmune diseases, such as Type 1 diabetes and rheumatoid arthritis, may offer opportunities for additional insights into digital networks, or ways sensors and software solutions might help patients. In my view, software models, made more realistic by clinical research, will help researchers understand the structure and function of the human nervous system and, along the way, make telecommunications networks and services faster and more reliable and secure.</p><img src="https://counter.theconversation.com/content/108319/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Salvatore Domenic Morgera has received R&D funding for networks from the Natural Sciences and Engineering Research Council, Fonds de recherche du Québec, National Science Foundation, and the United States Special Operations Command. </span></em></p>Biological research can inspire technological innovation. Also, software that models computer networks can inform health care for patients with neurological disorders.Salvatore Domenic Morgera, Professor of Electrical Engineering and Bioengineering, University of South FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1086602018-12-14T11:46:17Z2018-12-14T11:46:17ZTrump administration ban on NIH use of fetal tissue should worry all scientists<figure><img src="https://images.theconversation.com/files/250477/original/file-20181213-178576-32dhei.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Researchers studying Alzheimer's disease use fetal tissue for their experiments.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/alzheimers-disease-on-mri-3-664361182">Atthapon Raksthaput/Shutterstock.com</a></span></figcaption></figure><p>Throughout history, politicians have restricted or outright banned certain areas of scientific or medical research based on moral or ethical grounds. In some cases, these measures were justified and prevented <a href="https://www.cdc.gov/tuskegee/timeline.htm">unethical</a> <a href="https://www.hhs.gov/ohrp/regulations-and-policy/belmont-report/read-the-belmont-report/index.html">human</a> or <a href="https://history.nih.gov/research/downloads/nuremberg.pdf">animal</a> research. In others, the bans could be seen as misguided and delaying medical advances.</p>
<p>The use of human fetal tissue for research purposes has been highly contentious and tightly regulated, given that access to this tissue is directly associated with a woman’s right to choose an abortion since the tissue is procured from human fetuses. In 1993, <a href="https://www.guttmacher.org/gpr/2001/02/human-embryo-and-fetal-research-medical-support-and-political-controversy">Congress approved the use of federal funds for fetal tissue research</a>. Recently, prompted by <a href="https://www.sba-list.org/wp-content/uploads/2018/09/Group-Letter-to-Azar-FDA-and-fetal-tissue-FINAL-with-Signatures.pdf">anti-abortion groups</a> and <a href="https://chrissmith.house.gov/uploadedfiles/2018-09-17_-chs-hartzler-walker_letter_on_fda_fetal_tissue_contract.pdf">supported by 85 Republican members of Congress</a>, <a href="https://www.hhs.gov/about/news/2018/09/24/statement-from-the-department-of-health-and-human-services.html">the Trump administration </a> <a href="http://doi.org/10.1126/science.aaw3165">banned the acquisition</a> of human fetal tissue for research conducted by scientists employed by the National Institutes of Health. In addition, several states, <a href="https://www.guttmacher.org/image/2016/state-laws-fetal-tissue-donation-and-research">including Indiana, Kentucky, Ohio and Oklahoma</a>, have banned the use of human fetal tissue in research at the state level. </p>
<p><a href="http://www.chp.edu/research/areas/infectious-diseases/coyne-lab/areas">I am a scientist</a> who studies the impact of viral infections on fetal development and postnatal health, with the goal of improving the well-being of infants and children. I believe that the highly politicized nature of human fetal tissue research and the ever-growing government restrictions on the use of this tissue will stymie scientific discovery and hinder the development of new treatments to reduce the burden of human disease.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/250338/original/file-20181212-110249-1nwxoxz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Fetal tissue is essential for understanding how the virus causes birth defects in the developing fetus.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Brazil-Zika-Kids-Boy-in-Bucket/5e23f5ea2be84f599be4d80a1ad07801/3/0">AP Photo/Felipe Dana</a></span>
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<h2>Uses for fetal tissue</h2>
<p>The use of human fetal tissue in medical research has resulted in many seminal discoveries that have directly improved human health. Several vaccines, including those against chickenpox (varicella) and Rubella virus, have saved millions of human lives and were <a href="https://www.chop.edu/centers-programs/vaccine-education-center/vaccine-ingredients/fetal-tissues">manufactured from viruses initially grown in human fetal-derived cells</a>.</p>
<p>Fetal tissue has also been used to develop <a href="http://doi.org/10.1146/annurev-virology-101416-041703">“humanized” mouse models of disease</a>. These models involve the transfer of specific cells isolated from human fetal tissue into mice that lack an immune system, thus allowing for studies in human cells in the context of a whole animal model. These models have proven invaluable for <a href="http://doi.org/10.1146/annurev-virology-101416-041703">revealing the biology of HIV infection</a> and for testing novel anti-HIV therapeutics. </p>
<p><a href="https://www.nytimes.com/2016/02/02/health/zika-virus-world-health-organization.html">The recent outbreak</a> of <a href="https://www.cdc.gov/zika/index.html">Zika virus</a>, which causes a variety of malformations including microcephaly in a developing fetus, underscored the necessity to perform studies in human fetal tissue to identify how the virus is transmitted from the infected mother to her developing fetus. The human placenta, which forms the sole interface between the mother’s and her fetus’s blood throughout pregnancy, is structurally distinct from that of most small animal laboratory models, like the mouse or rat. Thus human-derived fetal tissue is essential to study the biology of Zika virus. </p>
<p>Outside of infectious disease research, <a href="http://doi.org/10.4103/1673-5374.241459">fetal tissue has provided insights into human neurological diseases</a> such as Alzheimer’s, which is expected to affect more than <a href="https://www.alz.org/alzheimers-dementia/facts-figures">5 million Americans over the age of 65 by 2050</a>.</p>
<p>Scientists can procure tissue from different sources, including mechanisms within a given institution or through a third-party vendor. However, <a href="https://www.guttmacher.org/gpr/2001/02/human-embryo-and-fetal-research-medical-support-and-political-controversy">it is illegal to profit </a> from the sale of human fetal tissue, a principle which was passed into law in 1993. </p>
<h2>Scientists become entangled in the fetal tissue debate</h2>
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<img alt="" src="https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=324&fit=crop&dpr=1 600w, https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=324&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=324&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=407&fit=crop&dpr=1 754w, https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=407&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/250336/original/file-20181212-110243-1qpisfz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=407&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Activists dressed as characters from ‘The Handmaid’s Tale’ leave the Texas Capitol Rotunda as they protest SB8, a bill that would require health care facilities, including hospitals and abortion clinics, to bury or cremate any fetal remains, rather than donate aborted fetal tissue to medical researchers.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Texas-Legislature/30efda175f6e43d9ad86d0e204560f0d/4/0">AP Photo/Eric Gay</a></span>
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<p>Scientists who use human fetal tissue in their research have themselves become subject to intense government scrutiny. During the Obama administration, Republican House member Marsha Blackburn from Tennessee – who has since been elected to the U.S. Senate – chaired a “<a href="https://archives-energycommerce.house.gov/select-investigative-panel">Select Investigative Panel</a> on Infant Lives” special committee that looked into the use of fetal tissue in research. </p>
<p>This committee was formed in direct response to heavily <a href="https://www.washingtonpost.com/politics/undercover-video-shows-planned-parenthood-exec-discussing-organ-harvesting/2015/07/14/ae330e34-2a4d-11e5-bd33-395c05608059_story.html">edited undercover videos</a> that purported to show the unethical sale of human fetal tissue by Planned Parenthood. In addition to investigating the sale of fetal tissue by Planned Parenthood and other suppliers, the panel also subpoenaed researchers to testify on the use of fetal tissue in their own studies. </p>
<p>The committee released its <a href="https://archives-energycommerce.house.gov/sites/republicans.energycommerce.house.gov/files/documents/Select_Investigative_Panel_Final_Report.pdf">final report</a> at the end of 2016 after an expensive 15-month investigation. Despite clear scientific evidence to the contrary, the <a href="http://www.sciencemag.org/news/2017/01/fact-checking-congress-s-fetal-tissue-report">committee concluded</a> that no significant medical advancements had ever resulted from the use of human fetal tissue and that the NIH should no longer fund any research that utilizes fetal tissue. </p>
<p>The committee instead advocated the use of other research models, such as cell lines isolated from cancerous tumors or rodent-based models, despite the fact that many of these systems do not accurately mimic key aspects of human biology and disease. In anticipation of possible restrictions imposed on human fetal research, the NIH is investing US$20 million toward <a href="http://time.com/5475726/human-fetal-tissue-research/">development of alternative models</a> and approaches. </p>
<h2>Scientific research requires freedom</h2>
<p>Many scientists might assume that they will be unaffected by these government restrictions. However, many commonly used cell lines, such as human embryonic kidney cells, which are used in research labs to produce protein, fall under the blanket definition of fetal tissue. Given their fetal origin, their use could be banned. </p>
<p>Moreover, as a scientist, I fear that this type of government regulation of scientific inquiry based on political nonscientific grounds sets a precedent that could affect every scientist in academia, industry or government. Indeed, the current administration ban on fetal tissue for researchers at the NIH could eventually spread to include all NIH-supported scientists. In this scenario, most research involving human fetal tissue would be stopped throughout the United States. </p>
<p>Scientific discovery requires freedom, and I believe it should be exempt from external political influences. This concept was established in the 1940s, when academic institutions began awarding tenure and the American Association of University Professors stated “<a href="https://www.aaup.org/report/1940-statement-principles-academic-freedom-and-tenure">The common good depends upon the free search for truth and its free exposition</a>.” </p>
<p>In my opinion, banning or restricting research with human fetal tissue derived from elective terminations has no moral or ethical purpose and serves only to fit a political agenda. All scientists should be alarmed by the actions of our government.</p><img src="https://counter.theconversation.com/content/108660/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Carolyn Coyne receives funding from the NIH.</span></em></p>The Trump administration has banned NIH researchers from using fetal tissue. The tissue is an essential tool for scientists investigating diseases ranging from Alzheimer’s to Zika virus infections.Carolyn Coyne, Professor of Pediatrics, University of PittsburghLicensed as Creative Commons – attribution, no derivatives.