tag:theconversation.com,2011:/id/topics/young-brain-27720/articlesYoung brain – The Conversation2019-11-05T15:05:47Ztag:theconversation.com,2011:article/1251492019-11-05T15:05:47Z2019-11-05T15:05:47ZEven mild hearing loss as a child can have long-term effects on how the brain processes sound<figure><img src="https://images.theconversation.com/files/297365/original/file-20191016-98670-1a607vj.jpg?ixlib=rb-1.1.0&rect=34%2C25%2C5716%2C3802&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/little-africanamerican-girl-hearing-problem-on-1007018965?src=KFdr11iccvaJcrnrOg8a7w-1-44">Africa Studio/ Shutterstock</a>, <span class="license">Author provided</span></span></figcaption></figure><p>When we are born, our brains have a lot to learn. For the newborn baby, everything they learn about the world around them comes from their senses. Therefore, if a child’s brain is deprived of sensory information, it will continue to develop, but in a different way.</p>
<p>A good example of this comes from children who are born deaf. Research has shown that adults who have been deaf since birth show changes in the way their brains process sensory information. Parts of the brain that would normally process sounds (the so-called auditory cortex) are also <a href="https://www.ncbi.nlm.nih.gov/pubmed/12960757">activated by visual stimuli</a>, for example.</p>
<p>However, we also know that timing is everything. If someone becomes deaf as an adult, their brains won’t suddenly change, if at all. But if a child is born deaf, early intervention is key. Such children would need to be fitted with cochlear implants <a href="https://www.ncbi.nlm.nih.gov/pubmed/12476090">within the first few years of life</a> if they wish to maximise their chances of being able to hear.</p>
<p>Until recently, scientists believed that these <a href="https://en.wikipedia.org/wiki/Critical_period">sensitive or critical periods</a> only applied in cases of severe sensory deprivation – for instance, in deaf children with little or no access to sounds. However, <a href="https://elifesciences.org/articles/46965">our research found</a> that even mild-to-moderate hearing loss in childhood was linked to changes in the way sounds are processed in the brain during adolescence.</p>
<p>In our study, we measured the brain responses of a group of children with <a href="https://www.actiononhearingloss.org.uk/hearing-health/hearing-loss-and-deafness/types-and-causes/">mild-to-moderate sensorineural hearing loss</a> while they were listening to sounds. Sensorineural hearing loss is a permanent hearing loss caused by damage to the inner ear, in this case <a href="https://www.nchearingloss.org/coch.htm#:%7E:text=The%20cochlea%20is%20the%20sense,your%20skull%20behind%20each%20ear.">the cochlea</a>. Those with “mild” hearing loss have a loss between 20-40 decibels – which typically makes it difficult to follow speech in noisy situations. Those with “moderate” hearing loss have a loss between 41-70 decibels, which makes it difficult to follow conversational speech without hearing aids. </p>
<p>The sounds they listened to varied, from simple non-speech sounds (such as a beep), to complex non-speech sounds (which sounded like speech, but without any distinguishable words or information). They also listened to speech sounds (complex both acoustically and linguistically). </p>
<p>We used a technique called electro-encephalography, or EEG, to measure the tiny amounts of electrical activity that happen in the brain in response to sounds. Because we know that <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2121131/">brain responses change during childhood</a>, even in those with normal hearing, we divided the children into 8-12 year-olds and 12-16 year-olds. We tested 46 children with hearing loss and 44 children with normal hearing, with roughly equal numbers in the younger and older groups. </p>
<p>We found several differences between the brain responses of children with hearing loss and those without hearing loss. But the most important finding related to a brain response that signals when the brain has detected a change in sounds. Whereas younger children with mild-to-moderate hearing loss showed relatively normal brain responses to a change in sounds, older children with hearing loss did not. In fact, on average, the brains of older children with hearing loss did not make these responses at all.</p>
<p>We didn’t believe the results at first, and thought that our findings might reflect historical differences between the younger test group and the older test group. For example, advances in medical screening and hearing aid technology may have differed between children born at an earlier point in time and those born later, resulting in better outcomes for the younger children. But to test whether our results were “real”, we needed to see what happened when the younger children got older.</p>
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<img alt="" src="https://images.theconversation.com/files/300227/original/file-20191105-88378-j8j6pb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/300227/original/file-20191105-88378-j8j6pb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/300227/original/file-20191105-88378-j8j6pb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/300227/original/file-20191105-88378-j8j6pb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/300227/original/file-20191105-88378-j8j6pb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/300227/original/file-20191105-88378-j8j6pb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/300227/original/file-20191105-88378-j8j6pb.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">We initially thought the results might have been because of advances in hearing aid technology for the younger participants.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/otolaryngologist-putting-hearing-aid-little-boys-1070495471?src=e5b72f02-2135-4da0-898b-23276d2a01e2-2-59">Pixel-Shot/Shutterstock</a></span>
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<p>We waited about six years before contacting the children with hearing loss who had been in the younger group (8-12 years old) during the initial study. These children were now between 13 and 17 years old, which was around the same age as the older group was in the first study. Of those we managed to contact, 13 agreed to come back to be retested. We used an identical test to that of six years earlier. </p>
<p>The results surprised us. Whereas, six years previously, the brains of these children had been able to detect a change in sounds, now these responses had either disappeared or grown smaller. It was as though their brains no longer “noticed” important differences between sounds – although these children could still discriminate differences, the responses indicating that the brain had detected a change had gone. The children’s level of hearing loss had remained the same as it was six years earlier. Therefore, our results suggested that changes were occurring in the brains of the children with hearing loss as they grew older.</p>
<h2>Earlier detection and better treatment</h2>
<p>Our findings raise a number of questions, both for science and for intervention. In our study, the sounds differed in loudness for children with hearing loss compared to those with no hearing loss. An important question to ask is whether we would find a similar pattern of results for normally hearing children, if we tested them using quieter sounds.</p>
<p>Assuming not, our findings may provide an explanation for the <a href="https://pubs.asha.org/doi/10.1044/2016_JSLHR-L-16-0297">higher-than-expected incidence of language difficulties</a> among children with hearing loss. An important next step will be to see if these brain changes are linked to language difficulties in these children, and if we can predict those at risk of future difficulties. </p>
<p>Since 2006, all babies born in the UK have been offered a newborn hearing screen within a few days of birth. However, mild hearing loss is not routinely screened for, so it isn’t detected in many of these children until later in childhood, if at all. Our research suggests that this may be too late. Also, while hearing aids do a good job at raising volume, they are currently unable to address many of the <a href="https://psyarxiv.com/h9x3p/">changes in sound quality</a> that children with hearing loss experience. It may therefore be that improvements in technology, combined with earlier intervention, will be key to stemming the brain changes associated with hearing loss in children before they occur.</p><img src="https://counter.theconversation.com/content/125149/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lorna Halliday receives funding from the Medical Research Council. </span></em></p><p class="fine-print"><em><span>Axelle Calcus receives funding from the H2020 Marie Skłodowska-Curie actions.</span></em></p>Children between 12 and 16 years old with mild-to-moderate hearing loss showed differences in their brain responses.Lorna Halliday, Principal Research Associate, University of CambridgeAxelle Calcus, Research fellow, École normale supérieure (ENS) – PSLLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/767832017-05-10T19:43:40Z2017-05-10T19:43:40ZExplainer: how the brain changes when we learn to read<figure><img src="https://images.theconversation.com/files/168547/original/file-20170509-11008-n9tvg0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Learning to read is not actually that easy. </span> <span class="attribution"><span class="source">from shutterstock.com </span></span></figcaption></figure><p>Right now, you are reading these words without much thought or conscious effort. In lightning-fast bursts, your eyes are darting from left to right across your screen, somehow making meaning from what would otherwise be a series of black squiggles.</p>
<p>Reading for you is not just easy – it’s automatic. Looking at a word and not reading it is almost impossible, because the cogs of written language processing are set in motion <a href="http://journals.sagepub.com/doi/abs/10.1177/0963721414540169">as soon as skilled readers see print</a>.</p>
<p>And yet, as tempting as it is to think of reading as hard-wired into us, don’t be fooled. Learning to read is not easy. It’s not even natural.</p>
<p>The first examples of written language date back to <a href="https://www.elsevier.com/books/forensic-document-examination/lewis/978-0-12-416693-6">about 5,000 years ago</a>, which is a small fraction of the 60,000 years or more that humans have spent using spoken language.</p>
<p>This means our species hasn’t had enough time to evolve brain networks that predispose us to learn literacy. It is only through years of practice and instruction that we have forged those connections for ourselves.</p>
<h2>How the brain learns to read</h2>
<p>Brains are constantly reorganising themselves. Any time we learn a new skill, connections between neurons that allow us to perform that skill become stronger. This flexibility is <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222570/?report=reader">heightened during childhood</a>, which is why so much learning gets crammed in before adolescence.</p>
<p>As a child becomes literate, there is no “reading centre” that magically materialises in the brain. Instead, a network of connections develops to link existing areas that weren’t previously linked. Reading becomes a way of accessing language by sight, which means it <a href="https://www.ncbi.nlm.nih.gov/pubmed/17964253">builds on architecture</a> that is already used for recognising visual patterns and understanding spoken language.</p>
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<img alt="" src="https://images.theconversation.com/files/168551/original/file-20170509-11023-1mqi2xc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/168551/original/file-20170509-11023-1mqi2xc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/168551/original/file-20170509-11023-1mqi2xc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/168551/original/file-20170509-11023-1mqi2xc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/168551/original/file-20170509-11023-1mqi2xc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/168551/original/file-20170509-11023-1mqi2xc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/168551/original/file-20170509-11023-1mqi2xc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&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">Words and letters are initailly stored in the brain as symbols.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
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<h2>The journey of a word</h2>
<p>When a skilled reader encounters a printed word, that information travels from their eyes to their occipital lobe (at the back of the brain), where it is processed like any other visual stimulus.</p>
<p>From there, it travels to the left fusiform gyrus, otherwise known as the brain’s “letterbox”. This is where the black squiggles are recognised as letters in a word. The letterbox is a special stopover on the word’s journey because it only develops as the result of learning to read. It doesn’t exist in <a href="https://www.ncbi.nlm.nih.gov/pubmed/20395549">very young children</a> or <a href="https://www.ncbi.nlm.nih.gov/pubmed/21071632">illiterate adults</a>, and it’s activated less in <a href="http://journals.sagepub.com/doi/abs/10.1111/j.1467-8721.2006.00452.x">people with dyslexia</a>, who have a biological difference in the way their brains process written text.</p>
<p>Words and letters are stored in the letterbox – not as individually memorised shapes or patterns, but as symbols. This is why a skilled reader can recognise a word quickly, regardless of <em>font</em>, cAsE, or <a href="http://www.unicog.org/publications/Dehaene%20Review%20Cognitive%20neuroscience%20of%20Reading%20and%20Education%202011.pdf"><strong>typeface</strong></a>.</p>
<p>Information then travels from the letterbox to the <a href="http://onlinelibrary.wiley.com/doi/10.1111/apa.13018/abstract">frontal and temporal lobes</a> of the brain, to work out word meaning and pronunciation. These same areas are activated <a href="https://www.ncbi.nlm.nih.gov/pubmed/18838044">when we hear a word</a>, so they are specialised for language, rather than just reading and writing.</p>
<p>Because information can travel so quickly across the skilled reader’s synaptic highways, the entire journey takes <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2734884/">less than half a second</a>.</p>
<p>But what happens in the brain of a five-year-old child, whose highways are still under construction?</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/168667/original/file-20170510-7902-1f0aslv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/168667/original/file-20170510-7902-1f0aslv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=404&fit=crop&dpr=1 600w, https://images.theconversation.com/files/168667/original/file-20170510-7902-1f0aslv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=404&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/168667/original/file-20170510-7902-1f0aslv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=404&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/168667/original/file-20170510-7902-1f0aslv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=508&fit=crop&dpr=1 754w, https://images.theconversation.com/files/168667/original/file-20170510-7902-1f0aslv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=508&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/168667/original/file-20170510-7902-1f0aslv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=508&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">Learning to read takes a lot of effort.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
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<h2>The growing brain</h2>
<p>For young children, the process of getting from print to meaning is slow and effortful. This is partly because beginning readers have not yet built up a store of familiar words that they can recognise by sight, so they must instead “sound out” each letter or letter sequence.</p>
<p>Every time children practise decoding words, they forge new connections between the visual and spoken language areas of the brain, gradually adding new letters and words to the brain’s all-important letterbox.</p>
<p>Remember, when a practised reader recognises a word by sight, <a href="http://www.unicog.org/publications/Dehaene%20Review%20Cognitive%20neuroscience%20of%20Reading%20and%20Education%202011.pdf">they process the letters</a> in that word, rather than its shape. </p>
<p>Literacy instruction can therefore support children’s learning by highlighting the symbolic nature of letters - in other words, by drawing attention to the relationships between letters and speech sounds.</p>
<p>Here, evidence from <a href="https://www.ncbi.nlm.nih.gov/pubmed/20395549">brain imaging research</a> and <a href="https://czone.eastsussex.gov.uk/sites/gtp/library/core/english/Documents/phonics/A%20Systematic%20Review%20of%20the%20Research%20Literature%20on%20the%20Use%20of%20Phonics%20in%20the%20Teaching%20of%20Reading%20and%20Spelling.pdf">educational research</a> converge to show that early <a href="https://theconversation.com/explainer-what-is-phonics-and-why-is-it-important-70522">phonics</a> instruction can help construct an efficient reading network in the brain.</p>
<h2>What might the future hold for literacy development?</h2>
<p>As technology evolves, so too must our definition of what it means to be “literate”. Young brains now need to adapt not only to written language, but also to the fast-paced media through which written language is presented.</p>
<p>Only time will tell how this affects the development of that mysterious beige sponge between our ears.</p><img src="https://counter.theconversation.com/content/76783/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nicola Bell 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>We are not hard-wired to read. It has taken thousands of years of practice to forge connections in our brains to help us do this.Nicola Bell, PhD student, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/674682016-10-24T09:19:46Z2016-10-24T09:19:46ZHow we discovered that heading a football causes impairment of brain function<figure><img src="https://images.theconversation.com/files/142776/original/image-20161023-15969-syoa2e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cristiano Ronaldo heading a football.</span> <span class="attribution"><span class="source">Alejandro Ramos/wikipedia</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Heading a football may look effortless but many scientists have suspected it might actually harm the player’s brain. There could be real consequences – we know that brain injury is linked to an <a href="http://www.annualreviews.org/doi/full/10.1146/annurev-pathol-012615-044116?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed&">increased risk of dementia</a>, for example. However, it has proven surprisingly difficult to find out the true impact of football heading, partly because mild brain injury is notoriously difficult to detect.</p>
<p>Now <a href="http://www.ebiomedicine.com/article/S2352-3964(16)30490-X/fulltext">our new research</a>, published in EBioMedicine, suggests that just a single session of heading practice results in temporary impairment in memory and a disruption of the normal balance of chemicals in the brain. We must now investigate whether these effects remain temporary after repeated football heading exposure and what the long-term consequences on brain health are.</p>
<p>Much of what we know about the brain is based on research on the mature brain, but the human brain is not fully developed until our early twenties. The frontal lobes are especially late to mature. This part of the brain, which absorbs the impact of the ball, is home to uniquely human qualities such as impulse control and conscious planning. In the teenage years brain chemicals are in a state of flux and the brain is very sensitive in lots of ways. A massive <a href="https://www.youtube.com/watch?v=6zVS8HIPUng">process of reorganisation of connections</a> takes place before the brain calms down in its mature state. </p>
<h2>The experiment</h2>
<p>A typical football practice drill involves many repetitions heading the ball. So what happens to the brain when these head impacts are repeated over and over again – particularly when done from a young age? </p>
<p>To find out, we used a sensitive research technique from our basic neuroscience lab to conduct our study. Transcranial magnetic stimulation uses a coil held over a person’s head to generate a brief magnetic pulse stimulating a small area of the brain. This, together with electrodes placed over the muscle, can be used to measure neural signals from the brain to the muscle.</p>
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<p>From this we can work out the level of “inhibitory chemicals” in the brain. These can interrupt or block certain brain activity and potentially make muscles more difficult to control, for example. In particular we look at the <a href="http://thebrain.mcgill.ca/flash/d/d_04/d_04_m/d_04_m_peu/d_04_m_peu.html">brain signalling chemical called GABA</a>, which is the most powerful inhibitor in the brain’s motor system. If there is more inhibition in the brain it means that the normal brain chemistry is changed after hitting the ball with the head.</p>
<p>We asked a group of football players to head a ball 20 times, fired from a ball machine to simulate the pace and power of a corner kick. Before and after the heading sessions, we tested players’ brain inhibition measured using transcranial magnetic stimulation, and players’ cognitive function such as memory. We monitored these same levels again the next day, the day after that, and two weeks after the heading session in the lab. </p>
<p>We found that football heading resulted in immediate and measurable changes in brain function. Increased inhibition in the brain was detected after just a single session of heading. Memory test performance was also reduced by between 41 and 67%. </p>
<p>The good news is that these changes in brain function were transient, with effects normalising within 24 hours. The bad news is that we do not know whether there is an accumulative effect when this biochemical disruption is repeated over and over again through weekly heading practice drills, or what the long-term consequences of heading on brain health are. This is why further research is needed.</p>
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<img alt="" src="https://images.theconversation.com/files/142775/original/image-20161023-15941-170t84b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/142775/original/image-20161023-15941-170t84b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=427&fit=crop&dpr=1 600w, https://images.theconversation.com/files/142775/original/image-20161023-15941-170t84b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=427&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/142775/original/image-20161023-15941-170t84b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=427&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/142775/original/image-20161023-15941-170t84b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=536&fit=crop&dpr=1 754w, https://images.theconversation.com/files/142775/original/image-20161023-15941-170t84b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=536&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/142775/original/image-20161023-15941-170t84b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=536&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">Heading a football seems to release the inhibitory brain chemical GABA.</span>
<span class="attribution"><span class="license">Author provided</span></span>
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<p>Now that we know that heading a football changes the biochemistry of the brain, at least temporary, we would like to visualise the effects of heading by using a brain scanner. In a brain scanner we can see how micro-damage to brain structure and brain connections relates to changes in the biochemistry of the brain. This would give us a much better idea of what goes on in the brain as a result of heading the ball. Therefore the research we have done is just a first step on the journey of finding out what is the true impact of football heading.</p>
<h2>Should we let kids play football?</h2>
<p>So what does this mean for players of the beautiful game? If there is more inhibition in the brain immediately after heading the ball, this could affect control of the muscles which may impair performance and expose the player to greater injury risk – something that has <a href="http://bjsm.bmj.com/content/early/2015/12/01/bjsports-2015-094982.abstract">previously been reported</a> in people who have had a concussion. </p>
<p>It is also important to realise that there are no known safe levels of football heading. One header is unlikely to give you brain damage, but how many headers do? At what levels of exposure do we enter the grey zone?</p>
<p>It is perhaps a bit like alcohol, there are <a href="http://www.medscape.com/viewarticle/824237">no known safe limits for alcohol</a> consumption. Disrupting the brain chemistry during brain development until late adolescence may warrant extra caution. Hopefully, further research can shed some more light on long-term health implications.</p><img src="https://counter.theconversation.com/content/67468/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Magdalena Ietswaart receives funding from The National Institute of Health Research (NIHR) Brain Injury Healthcare Technology Cooperative.</span></em></p><p class="fine-print"><em><span>Angus Hunter receives funding from `sportscotland institute of sport</span></em></p><p class="fine-print"><em><span>Thomas Di Virgilio receives funding from NIHR (National Institute for Health Research).</span></em></p>A single session of football heading can temporarily impair memory. So what does that mean for children with developing brains?Magdalena Ietswaart, Cognitive Neuroscientist and Associate Professor, University of StirlingAngus Hunter, Reader in Exercise Physiology, University of StirlingThomas Di Virgilio, PhD student in Psychology, Health and Exercise Sciences, University of StirlingLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/593402016-05-24T00:53:20Z2016-05-24T00:53:20ZThe hefty price of ‘study drug’ misuse on college campuses<figure><img src="https://images.theconversation.com/files/123640/original/image-20160523-10986-fuyguu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Using medicines to stay awake?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/sterlic/6294653409/in/photolist-aAeKa4-nwViJK-MivL-qG5xTB-6SZrLQ-8Ro81K-qnbxxH-6qG5pW-bPuNP8-9qpoXB-b57fhH-fjKAB8-9vNKo4-p1sJc1-mVaikP-qYPJAD-8SNxMK-7pQB4R-d2eM9u-d4SY4j-9EZyfd-bd6bwc-5TpsEP-fjZbYd-dB52N1-oUPT8j-dLAvY3-7pQBiD-9ZakZE-5Z5ran-FWL4nF-nypDAr-4KSNpu-qSPDY6-ej6efr-oU5vJH-cZVjJ-8gzV2K-bE9jtV-8gDbAb-bd6cqe-7pUvZE-aKd4z-oZZ9UQ-bd6bSK-aKnTU-dnf1dp-de89m2-ajMh17-muKvUu">Scott Akerman</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Nonmedical use of Attention Deficit Hyperactivity Disorder (ADHD) drugs on college campuses, such as Adderall, Ritalin, Concerta and Vyvanse, has exploded in the past decade, with a <a href="http://www.cnn.com/2014/04/17/health/adderall-college-students/">parallel rise in depression disorders</a> and binge drinking <a href="http://jod.sagepub.com/content/35/2/431.abstract">among young adults</a>. </p>
<p>These ADHD drugs act as a brain stimulant that are normally prescribed to individuals who display symptoms of ADHD. These stimulants boost the availability of dopamine, a chemical responsible for transmitting signals between the nerve cells (neurons) of the brain. </p>
<p>But now a growing student population has been using them as <a href="http://www.jhsph.edu/news/news-releases/2016/adderall-misuse-rising-among-young-adults.html">“study” drugs</a> – that help them stay up all night and concentrate. According to a 2007 National Institutes of Health (NIH) study, abuse of nonmedical prescription drugs among college students, such as ADHD meds, increased from <a href="http://publichealth.hsc.wvu.edu/media/4239/college_students_no-samhsa-logo.pdf">8.3 percent in 1996 to 14.6 percent</a> in 2006. </p>
<p>Besides helping with concentration, dopamine is also associated with <a href="http://www.news-medical.net/health/Dopamine-Functions.aspx">motivation and pleasurable </a> feelings. Individuals who use these ADHD drugs nonmedically experience a surge in dopamine similar to that <a href="http://www.dea.gov/druginfo/all_fact_sheets.pdf">caused by illicit drugs</a> which induces a great <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3489818/">sense of well-being</a>.</p>
<p>My journey with investigating the effect of the stimulant use nonmedically on college campuses started with a question from a student seven years ago. The question was about the long-term effect of misuse on brain and physical health. Having an educational background in cell and molecular biology with a concentration in neuroscience, I started a literature review and soon became an educator on the topic to teach students about the effects of such stimulant misuse on the maturing brain. </p>
<p>College students who take ADHD drugs without medical need could risk developing drug dependence as well as a host of mental ailments.</p>
<h2>Substance abuse in college</h2>
<p>College students have been reported to use many stimulants, including but not limited to Adderrall, Ritalin and Dexedrine.</p>
<p>According to the [2008 National Survey on Drug Use and Health](http://www.cpamm.org/wp-content/uploads/Nonmedical-use-of-Adderall-among-full-time-college-students-National-Survey-on-Drug-Use-and-Health-copy.pdf “), students who used Adderall for nonmedical purposes were three times more likely than those who had not used Adderall nonmedically to use marijuana. They were also eight times more likely to use cocaine. In addition, 90 percent of the students who used Adderall nonmedically were binge alcohol consumers. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/123642/original/image-20160523-11017-3hdier.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/123642/original/image-20160523-11017-3hdier.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=434&fit=crop&dpr=1 600w, https://images.theconversation.com/files/123642/original/image-20160523-11017-3hdier.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=434&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/123642/original/image-20160523-11017-3hdier.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=434&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/123642/original/image-20160523-11017-3hdier.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=546&fit=crop&dpr=1 754w, https://images.theconversation.com/files/123642/original/image-20160523-11017-3hdier.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=546&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/123642/original/image-20160523-11017-3hdier.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=546&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">College students use ADHD drugs as ‘study’ drugs.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/23771587@N08/2407983862/in/photolist-4EMxH9-5X1GPG-7BS5E-duRER9-ahUuLL-bdWZM-5UMYdH-9GyVfU-pBXsna-MLfj8-q9pQ25-PMEmN-zHSpf-9quskY-MLfj2-9BWys2-7QkfZe-9s3V83-e2sE9j-a2Y1au-5VBQy7-4Kp6DV-e8QZao-78qrg-qHSN9E-dxCiKs-7rC4b5-b3Yp6i-3d9wsL-7Qkg14-2XPVtm-7QkfZk-7CFTUE-8GjD54-e27bVF-9rY515-btKHVh-7hBJ2U-8kgBL6-2VG9A-awqshF-4oWpoY-7rdMKN-AJEs2-78qjG-9DMcXu-6izEyx-57gmMy-cxx2cW-7CFU6s">David A Ellis</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Generally, college students who abuse ADHD drugs are white, male and part of a fraternity or a sorority. Often they have a <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2906759/">low GPA as well</a>.</p>
<p>ADHD drugs appear harmless to many, as often they are prescribed by physicians, even though these drugs have a <a href="http://www.fda.gov/downloads/ForConsumers/ConsumerUpdates/UCM107976.pdf">"Black Box warning,”</a> which
appears on a prescription drug’s label to call attention to serious or life-threatening risks. Despite such a strict warning from the FDA, <a href="http://www.modernhealthcare.com/article/20140318/NEWS/303189948">many practitioners end up prescribing them</a> based on subjective reporting of symptoms of ADHD. The lack of a gold standard for ADHD diagnosis has, in fact, led to physicians overprescribing the drug.</p>
<p>Furthermore, students who get hold of these prescriptions can <a href="http://www.healthline.com/health-news/1-in-6-college-students-misuses-adhd-drugs-033015">easily sell pills</a> on the black market. Students who buy these pills illicitly miss seeing the warning about potential abuse, <a href="http://psychcentral.com/news/2015/06/03/misuse-of-stimulants-and-adhd-drugs-begins-young/85305.html">addiction and other side effects</a>. </p>
<p>What’s more, a chewable form of an ADHD drug <a href="https://www.statnews.com/2016/05/23/adhd-drug-concerns/">has been recently introduced</a> in the market. These are fruity-flavored extended-release drugs that dissolve instantly in the mouth. They are targeted for children for a fast medicated response, but present a great potential for abuse.</p>
<h2>The neurobiology of addiction</h2>
<p>What are the consequences of taking these drugs without a medical condition?</p>
<p>The nonmedical use of the ADHD drugs (stimulants) is of great concern because it raises levels of dopamine the same way illicit drugs do. Therefore, abuse of these drugs may cause the same effect on addiction, brain rewiring and behavioral alteration. </p>
<p>While students may be aware of the harmful effects of “doing drugs,” the use of the ADHD drugs nonmedically may seem harmless because they are prescription medicine. </p>
<p>There is a limited body of knowledge on the effect of long-term nonmedical ADHD drug abuse on the developing brain. Of concern are potential permanent alterations taking place in the pathways of nerve cells of the maturing brain. </p>
<p>ADHD drugs could be addictive, if used without medical necessity. Since brain development continues into the mid-20s and the young brain is remarkably plastic, this sets up a risk of developing chronic substance abuse, addiction and mental ailments. </p>
<p>Nonmedical ADHD drugs, like any illegal drug, collectively activate a nerve pathway known as the “reward system of the brain.” This reward system is responsible for positive feelings such as motivation and pleasure. From an <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1174878/">evolutionary point of view</a>, the circuit controls an individual’s responses to <a href="https://www.drugabuse.gov/publications/teaching-packets/neurobiology-drug-addiction/section-ii-reward-pathway-addiction/2-natural-rewards">motivation and pleasure</a> (e.g., food and sex) which promote survival and fitness, respectively. </p>
<p>The response of the brain reward system to natural cues is highly regulated by a homeostatic mechanism – a process by which the body maintains its constant internal environment.</p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/123646/original/image-20160523-11000-1huheg6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/123646/original/image-20160523-11000-1huheg6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/123646/original/image-20160523-11000-1huheg6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/123646/original/image-20160523-11000-1huheg6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/123646/original/image-20160523-11000-1huheg6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/123646/original/image-20160523-11000-1huheg6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/123646/original/image-20160523-11000-1huheg6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Individuals can ‘function’ only when the brain is on drugs.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/stevensnodgrass/6010535530/in/photolist-aa8yNW-qkS3BQ-qkSwY9-3LzMpi-8pKWoG-5TnncS-7eKXWM-3LzJRV-q4vw5D-qkVRWg-qiDkb3-q4nGw9-fj4H3t-qkS1kA-oaJmWV-3LzV9D-7KM6G-3KKJ4H-3LEa1J-Kj3d2-ppaGpv-9bpCS-3LAm1p-q4mYT7-h8vaGm-q4nPqj-fC2ohB-2Gzrkq-q4nz8u-3LzTqr-qkKh9H-q4vZYp-5VsjSj-3LA15Z-q4nzs9-q4nc37-9XSqU5-3LEBNY-cDjeQw-ppaKAv-q4nmNj-qkS7c5-9veq9f-q4nrhj-eYzZGF-qkKtAv-n8TLTa-8q5ybg-q4nFnL-rvi1Ud">Steve Snodgrass</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>However, a nonmedical ADHD drug, like an illegal drug, overactivates this “reward circuit,” thereby disturbing the brain’s internal balance. This causes the brain to maladapt (structurally and functionally) and turn the brain into being “substance-dependent.” These <a href="http://www.ncbi.nlm.nih.gov/pubmed/21614102">changes happen at the genetic level</a>. </p>
<p>A consequence of this is that the brain starts to need an increased dosage of the drug to respond to the natural cues for motivation and life pleasures. This sets the stage for more substance abuse. The individual then reaches for higher doses and more potent substances. <a href="https://www.drugabuse.gov/publications/teaching-packets/neurobiology-drug-addiction/section-iii-action-heroin-morphine/6-definition-tolerance">Eventually, a cycle</a> of further dependence and drug abuse ensues.</p>
<h2>Impact of abuse</h2>
<p>The concern with the nonmedical ADHD drug abuse is that it might prime the brain for use of other substances such as alcohol, cocaine and marijuana (something that the national surveys mentioned above revealed).</p>
<p><a href="http://www.ncbi.nlm.nih.gov/books/NBK64178/">Major behavioral changes</a> emerge such as compulsive drug seeking, <a href="http://ukcia.org/research/AgressiveBehavior.pdf">aggression, mood swings</a>, psychosis, abnormal libido and suicidal thoughts. </p>
<p>In fact, there have been <a href="http://www.nytimes.com/2013/02/03/us/concerns-about-adhd-practices-and-amphetamine-addiction.html?_r=0">documented cases of college students</a> who have taken their lives following an addiction to nonmedical ADHD drugs.</p>
<p><a href="http://www.ncbi.nlm.nih.gov/pubmed/23359110">Animal studies</a> show that the changes that lead to rewiring of the brain are due to an alteration in gene function. Some of these changes become permanent and heritable, especially with prolonged abuse, meaning that the <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3872494/">altered (newly programmed) genes</a> are passed down to offspring.</p>
<p>In fact, a body of evidence is linking the process of addiction (among many chronic diseases) to <a href="http://press.endocrine.org/doi/full/10.1210/en.2010-1461">altered gene function profile</a> passed down by ancestors. This altered profile could <a href="http://www.biologicalpsychiatryjournal.com/article/S0006-3223(10)00576-7/fulltext?mobileUi=0">predispose</a> their offspring to certain disorders. </p>
<p>Currently, prescription of ADHD drug is based mostly on subjective self-reported symptoms, and a gold standard for ADHD diagnosis remains to be perfected. As a lyric from the rock band Marilyn Manson says: </p>
<blockquote>
<p>Whatever does not kill you, it’s gonna leave a scar.</p>
</blockquote>
<p>That’s the case with nonprescription ADHD drug abuse.</p><img src="https://counter.theconversation.com/content/59340/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lina Begdache does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>College students who take stimulants such as Adderall to get an academic edge might be setting themselves up unknowingly to a vicious cycle of substance abuse and addiction.Lina Begdache, Research Assistant Professor, Binghamton University, State University of New YorkLicensed as Creative Commons – attribution, no derivatives.