The causes of stuttering have long remained a mystery. Over time, people have been led to believe that stuttering can be caused by psychological issues or develop due to parenting style. But, experts are discovering that these beliefs may not be true. Recent research has started to develop the idea that stuttering is actually caused by a structural problem in the brain.
Dr. Scott Grafton, Professor of Psychological and Brain Sciences at University of California, Santa Barbara explains that diffusion MRI scanning has been used in research to discover that a large portion of the arcuate fasciculus was missing in seven of the eight stutterers, but it was present in all of the non-stutterers. The arcuate fasciculus connects two parts of the brain that allow for language function, so if these parts of the brain are not connected, an individual’s ability to perform classic language functions can be affected.
Another cause of stuttering in speech is related to issues of perception. Dr. Devin McAuley, Professor of Psychology and Neuroscience at Michigan State University states that individuals who have a difficult time discerning musical beats may also have a hard time picking up on natural speech rhythms, too. This inability to perceive beats may induce a stutter in an individual because they are not capable of timing their speech due to an issue in generating natural rhythms of language.
How can these new discoveries help doctors develop new treatments for those who suffer from a stutter? Dr. Roger Ingham, Professor of Speech and Hearing Sciences at University of California, Santa Barbara explains one new method of altering speech. It is called modifying phonation intervals (MPI) which is a treatment that trains people to reduce the frequency of very short intervals of phonation in order to create fluent speech. While MPI treatment works about twice as well as other speaking treatments, there is still plenty of research to be done in order to increase the effectiveness of treatments for stutters.
- Dr. Roger Ingham, Professor of Speech and Hearing Sciences at University of California, Santa Barbara
- Dr. Scott Grafton, Professor of Psychological and Brain Sciences at University of California, Santa Barbara
- Dr. Devin McAuley, Professor of Psychology and Neuroscience at Michigan State University