For the 1% of adults worldwide who stutter, the everyday task of picking up a phone, asking for directions, or ordering food in a restaurant can be incredibly difficult.
Stuttering is even more common in young children: as many as 4% of children go through a phase where they repeat or prolong sounds or words, or get “stuck” trying to talk. Stuttering typically emerges between the ages of two and four, after children have already been speaking normally. As with many other childhood conditions, 80% of stuttering goes away, typically well within two years after it first appears.
At this point, we don’t know if very young children’s recovery from stuttering is aided by therapy, as therapies for stuttering in preschoolers don’t achieve a significantly higher success rate than the reported rate of spontaneous, untreated recovery.
Why does a person stutter?
Nobody knows what causes stuttering, but some hypotheses are increasingly being disproved while others gain support.
The common misconception that stressful events or unresolved psychological problems in young childhood causes stuttering, for instance, has literally no evidence base. This was a popular theory earlier in the 20th century and was explored in the storyline of the film The King’s Speech to explain why King George VI started to stutter. But stuttering is not improved by psychological therapies, which indicates it does not have a psychological cause.
At the same time, genetics research, sophisticated brain imaging and motor coordination research support the likelihood that stuttering is caused by trouble integrating the brain “circuits” that control language formulation and translating of spoken messages into smooth motor actions. This suggests that a person is genetically predisposed to stutter.
Dennis Drayna, a geneticist at the American National Institute of Health, has identified a number of plausible candidates for a gene or multiple genes, or genetic mutations, that appear to disproportionately affect people who stutter.
Luc De Nil and colleagues at the University of Toronto have demonstrated in a series of studies that people who stutter take more time to learn novel motor tasks, make more errors on such tasks and have performance profiles that suffer when they are asked to complete two tasks at the same time.
Researchers Anne Smith and Christine Weber-Fox at Purdue University have been able to use the same group of children and adults who stutter to show that they tend to demonstrate less stable motor coordination while learning a new activity, such as tapping a rhythm. They have also shown that participants’ speech motor coordination is disproportionately affected by tasks requiring more sophisticated language skills.
This study also demonstrated that people who stutter display very subtle differences in how the brain processes language, even when listening to speech input, as opposed to talking. Such findings point to a very complex communication disorder which combines genetic predispositions with difficulties in integrating across many learning, motor and language systems, which may explain why it has not been easy to find a simple, single explanation for stuttering.
Stuttering is a very handicapping condition that impacts social interactions, vocational aspirations and even educational achievement. That’s why it’s important to seek out good therapy, even for very young children, if they are discomforted by their speaking difficulties.
Many two year olds who have trouble speaking fluently seem oblivious to their problem and only their parents are concerned. Other toddlers, however, openly express that they are “stuck”, show signs of physical frustration, or start avoiding words that have caused them difficulty in the past. Any of these negative reactions by the child are reasons to seek immediate help, to make speaking easier and less frustrating to the child.
Therapies that can help
There are a number of documented options for improving fluency and for navigating moments when speech doesn’t come easily.
For older children and adults, the two main approaches teach ways to help people speak more fluently, such as gentler use of voice and the articulators: the tongue and lips. Alongside this, speech therapists teach ways in which the person who stutters can “slide” more easily out of a moment of stuttering with less obvious struggle and blockage.
For both types of therapy, it may be useful to add a series of components that deal with the speaker’s fears about speaking and stuttering – which can be counterproductive to using any new skills learnt in therapy – and “unlearning” any maladaptive strategies.
Maladaptive strategies, such as trying to force or push “stuck” words out or gulping air before speaking, have sometimes been taught by well-meaning parents or friends. Stutterer are [often advised by](http://www.stutteringhelp.org](http://www.stutteringhelp.org) those closest to them to “take a deep breath and try again” when they see them having trouble – this is particularly common advice for children. But we now know it is likely to be counterproductive, rather than helpful.
For very young children, a program called Lidcombe, developed at the Australian Stuttering Research Centre in Sydney, has shown to be an effective way to more quickly move preschoolers who stutter into fluency. This is achieved by partnering speech-language pathologists with the child’s parents to create a home-based plan of intervention.
While no single therapy has shown to be the “best”, these techniques can help people of any age to speak more fluently, with less struggle and frustration.
See more Explainer articles on The Conversation.