A speech disorder characterized by repetitions, prolongations, and blocks, stuttering is present in all races, cultures, and linguistic-communities. Not many people know that the list of stutterers include famous people such as Sir Isaac Newton, Winston Churchill, King George VI, Marilyn Monroe, and James Earl Jones.
Stuttering affects over 70 million people all over the world. Around 5% of children begin stuttering at a time they develop their speech and language skills. Out of these, nearly 1% of children continue stuttering into adulthood.
A pan-cultural condition, stuttering has been with us throughout time.
Significant research has been conducted over the last few decades to dissect the causes, symptoms, patterns, possible treatments, etc. associated with stuttering.
Here in this post, we will shed light on some of the most important research findings on stuttering. Read on.
The Brain and Stuttering
The ongoing neuroimaging investigations of stuttering have offered major clues to the neurological basis of the speech disorder.
Early research has mostly been focused on adults whose brain and behaviors are likely to have developed compensatory reactions to the disorder.
Therefore, researchers are now keen to use neuroimaging techniques to examine kids who stutter.
Researchers have found differences in brain structure and function in kids who stutter. Here, the ‘brain structure’ refers to the anatomy of the brain and the ‘function’ refers to how various systems within the brain work together.
The structural and functional differences have been observed in the brain’s auditory and motor areas.
New research in this area is focused on studying the differences in brains of
- Kids who recover (or stop stuttering) on their own versus
- Kids who continue to stutter
In brain scans of 70 kids aged between 3 to 10 years, researchers observed that kids with persisted stuttering have a deficit in the left hemisphere’s speech network.
Kids who outgrow stuttering, on the other hand, were found to have a compensatory mechanism in the same area.
Genetic Mutations and Stuttering
Genetic clues to stuttering were first discovered in 2005.
Five years later, in 2010, researchers were able to pinpoint the first genetic mutations responsible for causing stuttering.
Molecular geneticists at the time studied the DNA of 46 Pakistani families having several members who stuttered. The team of researchers led by Dr. Dennis Drayna from the National Institute on Deafness and Other Communication Disorders in Bethesda, Maryland were aware of the ‘pattern of inheritance.’
However, they wished to identify the genes responsible for causing stuttering. After having combed through more than 10m letters of DNA, the researchers found the mutation they were looking for, in a gene called GNPTAB.
Later on, they studied stuttering subjects in the US and England and found a total of 4 mutations in GNPTAB, 3 in GNPTG, and 3 in NAGPA. The findings were published in the New England Journal of Medicine.
New research led by Dr. Dennis Drayna points towards cellular causes of stuttering in kids and adults.
Family History and Stuttering
There is a genetic component to stuttering but researchers say it does not account for everything.
Twin and family studies have in the past suggested a strong genetic component.
In 2007, genome-wide linkage and association analyses revealed that familial aggregation of this condition is more likely in first degree relatives.
The Role of Anticipation in Stuttering
Often, people who stutter are able to identify a moment when they feel they are about to get stuck on a phrase or word.
Eric S Jackson, Assistant Professor in the Communicative Sciences and Disorders department at New York University, has characterized this moment as ‘anticipation.’
He defines anticipation in stuttering as “the sense that stuttering will occur before it is physically and overtly realized.”
Jackson has conducted numerous studies on kids, teens, and adults to explore the role of anticipation in stuttering.
In 2015, Jackson conducted a study of 30 stuttering adults. The study revealed that 77% of participants experienced ‘anticipation’ on a regular basis. All participants reported having experienced ‘anticipation’ on some occasions.
According to him, if a stutterer is able to “identify and measure” stuttering, he can become more aware of behaviors or actions that increase the frequency of speech disfluencies.
Gender Factor in Stuttering
On the basis of numerous studies and systematic follow-ups of many kids over an extended duration of time, researchers have now established that males have a greater risk of developing chronic stuttering.
According to the Stuttering Foundation, boys are 3.75 times more likely than girls to become chronic stutterers.
Previous research also suggests that the number of females who stutter is lesser because they have higher chances of recovering from stuttering at a young age.
However, among men and women who stutter as adults, the offspring of men are less likely to stutter than women.
According to the data compiled by ScienceDirect.com:
- Among men who stutter, 22% of their sons and 9% of their daughter will stutter
- Among women who stutter, 36% of their sons and 17% of their daughter will stutter
Is There A Cure for Stuttering?
So far, there is no ‘cure’ for stuttering.
Researchers have been studying pharmacological and non-pharmacological treatment options for many years now. So far, there is no FDA-approved drug for the treatment of speech disfluencies.
Some medicines can help in reducing the intensity of stuttering but a perfect medicine for stuttering is nowhere in sight.
At the moment, speech therapy or self-therapy are considered to be among the best treatment options available for stuttering.
Researchers have made significant strides in understanding the causes, symptoms, and treatments of stuttering over the last two decades.
However, the picture is far from complete.
Researchers are yet to pinpoint the exact causes of stuttering or ways to treat it completely.
In the near future, we hope that the scientific community would be able to discover ways or invent solutions to help millions of people overcome or manage their speech disfluencies more effectively.