Unraveling the Mystery: What Causes Stuttering?
September 6, 2020
American Institute for Stuttering
There are many myths and misconceptions about stuttering. Stuttering is not caused by emotional trauma, nor is it caused by anxiety. Instead, stuttering is a complex interaction of neurological, linguistic and emotional factors.
Some basic information about stuttering:
Learn more: Facts About Stuttering
You may have heard someone explain that stuttering “happens in the brain” or is a "neurodevelopmental disorder." But what does that mean, exactly? Neurological research on stuttering has found differences in a few key areas of brain activity.
For fluent speakers, most speech activity takes place in the left hemisphere of the brain. For people who stutter, that activity is more evenly distributed through the right and left hemispheres. There are also differences in the part of the brain that initiates movement, telling the muscles to change from “rest” to “go.” That may be one reason stuttering usually happens on the first sounds in words.
Another difference occurs in the parts of the brain that listen to your speech and adjust the movements as they happen. This makes sense when you remember that certain listening tasks - reading with others, hearing your own voice slightly delayed through electronic devices - have a significant impact on the symptoms of stuttering.
These are just a few of the brain features scientists have identified as they work to understand exactly how the brain impacts stuttering. It’s important to remember that none of these factors stands alone. Instead, they are all part of the complicated network of neurons and impulses that allows us to communicate.
Learn more: What Part Of The Brain Causes Stuttering?
When young children start to stutter, we consider the following factors to determine how likely it is that the child's stuttering will resolve (Singer et al., 2020).
While speech therapy does not significantly change the odds of a stutter resolving, early treatment can reduce the amount of stuttering and, more importantly, increase the child's ability to manage the stutter successfully, speak freely, and prevent possible complications to minimize life impact.
Parents sometimes ask us, "Is there anything I could have done to prevent stuttering in my child?" Research overwhelmingly shows that parents do NOT cause children to stutter. Other common myths that do NOT cause stuttering include:
By far the most common type of stuttering, developmental stuttering (sometimes referred to as "childhood onset fluency disorder") usually begins in early childhood. It is called "developmental stuttering" because it is a natural part of speech and language development, and usually begins as the child is learning to speak.
A number of factors contribute to the onset of developmental stuttering, including genetic predisposition to stutter, the child's speech production accuracy, the language development of the child, and the way the child's brain develops. Most children outgrow stuttering, while 20% continue to stutter into adulthood.
Acquired stuttering has its onset in adulthood. Stuttering diagnosed in adulthood is not always acquired stuttering; some people with developmental stuttering may not notice it as a child, but have it emerge as they encounter certain speaking situations as adults. Acquired stuttering is a specific stuttering type that started in adulthood, and comes in two forms: neurogenic stuttering and psychogenic stuttering. Both are very rare compared with developmental stuttering.
Neurogenic stuttering is a speech disorder that occurs due to a stroke, traumatic brain injury, or other disruption in the normal functioning of the brain.
People who acquire stuttering as adults are less likely to exhibit fluent speech under certain conditions such as delayed auditory feedback, unison reading, and singing - although these conditions vary widely between people, and may affect stuttering in some more than others. Speech therapy for acquired neurogenic stuttering is similar to speech therapy for developmental stuttering.
Psychogenic stuttering occurs when a person develops disfluent speech in the absence of an observable physical cause. A healthcare provider will usually rule out neurogenic causes and other factors prior to making a diagnosis.
The stuttering behavior associated with psychogenic stuttering is frequently more difficult to change at first, with fewer fluency-inducing conditions. However, unlike neurogenic and developmental stuttering, psychogenic stuttering can frequently resolve with a short course of speech therapy.
Yes, there is a genetic component to stuttering! Children and adults with a family history of stuttering are more likely to stutter themselves. Scientists are still looking for the exact cause in our DNA, and have learned that there may even be several different genes that impact speech fluency.
The core physical characteristics of stuttering are repetitions and prolongations during the normal flow of speech. But as people who stutter grow, they can develop struggle behaviors as they try to suppress the stutter.
Possible complications can include:
Stuttering is sometimes misunderstood as an articulation disorder, which it is not. People who stutter can form words and sounds accurately. It is also not a language disorder; people who stutter do not have trouble thinking of what they want to say.
Language problems and speech disorders can certainly co-occur with stuttering. The symptoms of stuttering are distinct, and include repeating certain syllables and stretching the first sounds of words.
Speech language pathologists can help evaluate children to determine whether they have other speech and language disorders. When disorders co-occur, a speech language pathologist can often treat both together.
Stuttering treatment has evolved enormously in our lifetimes. Early treatment included such zany ideas as talking with stones in your mouth, eating a certain diet, or, more recently, wearing electronic devices.
Stuttering treated in this way usually did not improve, and the stigma around speaking with a stutter was only heightened by treatments that focused on fluency at all costs.
Speech pathologists now treat stuttering holistically, understanding that each child brings their own set of circumstances to the table. The focus of speech therapy has increasingly moved away from fluency and toward the freedom to speak without shame or stigma.
Modern treatment with a speech pathologist who specializes in stuttering might include:
Understanding the causes of stuttering is just one part of the stuttering journey, but it can be an important one. It can provide a much-needed reminder that stuttering is not your fault - it's a genetic, neurological condition. Whether you are an adult or child, working with a speech language pathologist can help you speak freely, and live fearlessly.
