The biology of a perplexing condition: stuttering is being unraveled

Holly Nover spent her childhood attempting to conceal her stutter.

«I was quite self-conscious,» said the 40-year-old mother of a 10-year-old boy with a speech impairment from St. Johns, Florida. «As a result, I developed habits of switching my speech to avoid being observed.»

People have feared being judged for stuttering for decades, a disease that is sometimes misinterpreted as a psychological problem caused by factors such as poor parenting or emotional trauma. However, new research presented at a science conference on Saturday looks into the molecular underpinnings of the condition: genetics and brain abnormalities.

«We can reduce the stigma by better understanding biology. We’re going to raise the level of acceptance «Dr. Gerald Maguire, one of the speakers, told The Associated Press in a recent interview. He is a California psychiatrist who is active in scientifically based testing of prospective stuttering treatments.

President Joe Biden, who has spoken openly about being humiliated by classmates and a nun in Catholic school because of his speech impediment, is one of the 70 million individuals worldwide who stutter. He stated it was one of the most difficult things he’d ever done.

His problem was brought to light after a campaign event in 2020 when he met a New Hampshire youngster who similarly stuttered. Brayden Harrington said he wanted to shake hands with Biden after his father told him about him. They ended up conversing for over an hour.

Living with a stutter hasn’t been easy, Brayden said, describing a particularly trying day when he got stuck on words while reciting the Gettysburg address in class and went home crying.

He said, «I want to carry on what Joe Biden said to me.» «That this does not define you, and that you are capable of far more than you believe.»

WHAT CAUSES PEOPLE TO STUTTER?

The history of stuttering can be traced back to ancient China, Greece, and Rome. However, until current genetic science and brain imaging began to provide clues, no one really knew what caused it.

More than a decade ago, scientists discovered the first genes substantially connected to stuttering. Adults and older children were the subjects of imaging studies until recently, when Ho Ming Chow, a speech problem researcher at the University of Delaware, began looking at 3- to 5-year-olds. Around this age, many children start stuttering, with about 80% of them eventually growing out of it.

According to Chow, brain imaging demonstrates minor abnormalities in early children who continue to stutter as compared to those who recover and those who never stutter. He presented his findings at the American Association for the Advancement of Science conference on Saturday.

Stuttering genetic mutations, for example, have been linked to structural abnormalities in the corpus callosum, a bundle of fibers that connects the two hemispheres of the brain and ensures communication, as well as the thalamus, a relay station that sorts sensory information to other parts of the brain. Stuttering has also been related to the basal ganglia, which are brain areas involved in movement coordination.

«We know there’s a big genetic component to stuttering,» Chow added. Though numerous genes may be implicated, and the precise genetic causes may differ from child to child, «they certainly influence the brain in a similar way,» according to the researchers.

Evan Usler, a colleague of Chow’s, stutters and compares it to «yips,» or involuntary wrist spasms, experienced while golfing. According to the newest research, it’s a dysfunction of cognitive control over speech.

Many people mistakenly believe that people stammer because they are frightened, shy, or have experienced childhood adversity and that they could stop if they just tried harder.

According to Nan Bernstein Ratner of the University of Maryland, «we have a long way to go» in changing such ideas. «There’s still a lot of mythology out there,» says the narrator.

ACCEPTANCE AND FORWARD MOVEMENT

The mainstay of stuttering treatment is speech therapy. However, according to Maguire, who has stuttered since infancy, the drugs currently being investigated for stuttering could be approved in the next few years, first for adults and then for children.

Stuttering has been linked to high levels of dopamine, a chemical messenger in the brain, according to some studies, and some medications reduce dopamine activity or block it in a specific way.

Many individuals, said Nover, a speech pathologist who is involved with the National Stuttering Association, will be interested in trying stuttering drugs – but not her. She said she is content with her life as it is and has embraced her stuttering. However, if Colton was having trouble and wanted to try medicine as a teen, she would be open to the notion.

Brayden, now 14, isn’t one of them.

Taking drugs is like «taking away a piece of yourself…a piece of your individuality,» he explained.

He claims that if he hadn’t stuttered, he would not have aspired to be a speech and language therapist when he grew older. He would not have authored a children’s book with the intention of motivating others. And he wouldn’t have been able to overcome the obstacles that pushed him to be bold.