Are Stuttering and Tourette’s Related?
Editor: Thomas David Kehoe, an author and expert on stuttering therapy, contacted ACN because he saw a connection between our multidisciplinary approach to treating neurological disorders, and the need for a similarly comprehensive plan to treat stuttering. This article written by Kehoe for Latitudes.org offers a discussion of therapies including a fascinating treatment, through technology he developed, that brought his own severe stuttering under control.
A 1996 study of persons with Tourette’s and their families found that three genes that control levels of the neurotransmitter dopamine in the brain correlated with five disorders: attention deficit disorder (ADD), stuttering, Tourettes, tics, and obsessive-compulsive disorder (OCD). Individuals with these genes “switched on” were more likely to have one or more of these disorders.
Stuttering researchers ignored the study. Ten years later, speech-language pathologists continue to write that “someday a gene might be found for stuttering.”
Tourette’s experts questioned the validity of the study. It didn’t help that the study’s author, David E. Comings, wrote a controversial book entitled The Gene Bomb, hypothesizing that our increasingly complex society’s demands for higher education is selecting for genes associated with ADD, learning disabilities, and anxiety attacks.
Stuttering and Tourette’s appear to be sister disorders. Tourette’s has been characterized as “stuttering with your hands and feet.” Stutterers’ speech production muscles (breathing, vocal folds, lips, jaw, and tongue) are overactive, much as persons with Tourette’s are overactive with their hands and feet. Both disorders increase with certain types of stress. When stutterers try to control their stuttering, it becomes worse. However, stutterers can, with training, learn to substitute more acceptable speech motor behaviors when they talk, to minimize stuttering. Persons with Tourette’s report similar experiences.
Dopamine antagonists medications, such as Haldol, can be used to treat both stuttering and Tourette’s. However, few stutterers take medications because the effects on their speech are relatively small typically in the 30-50% range) and the side effects can be severe.
Stuttering has five other widely practiced treatments. Stuttering modification therapy (also called Van Riper therapy) was developed in the 1940s. In this therapy, more acceptable, “smoother” forms of stuttering are substituted for stuttering behaviors that disrupt the flow of speech. Stuttering modification therapy also emphasizes accepting that you stutter and voluntary stuttering, or stuttering on purpose. Only one study has investigated the efficacy of stuttering modification therapy. The study found that the therapy “appears to be ineffective in producing durable improvements in stuttering behaviors.”
Fluency shaping therapy was developed in the 1960s and 1970s. This therapy assumes that stuttering is, at least in part, a motor learning disorder. In other words, stuttering children learned maladaptive speech motor programs, which became hardwired into their brains as they mature into adulthood.
Fluency shaping therapy trains stutterers to speak with relaxed speech production muscles, such as relaxed breathing and relaxed vocal folds. Many efficacy studies have investigated fluency shaping therapy programs, usually finding that the therapy is effective for about 70-75% of stutterers.
Because certain types of stress increase stuttering, stuttering therapies usually include teaching stutterers to identify and better handle stress. A study found that stuttering temporarily reduced stress, as measured by systolic blood pressure. Stuttering appears to be a strategy to reduce stress, but a poor strategy that then causes stress, starting a cycle of a few fluent words disrupted by a dysfluent word.
Stuttering therapy programs may also include psychological treatment of speech-related fears and anxieties. For some adults, physical stuttering may be the “tip of the iceberg,” with psychological fears and anxieties being more disabling — for example, a stutterer may refuse to look for a job, and make the excuse that no one would hire him because he stutters. Interestingly, mild stutterers can have more severe fears and anxieties than severe stutterers.
Mild stutterers may be able to hide their stuttering, but live in fear that someone will discover their stuttering. In contrast, I stuttered severely and was never able to hide my stuttering.
I’ve left what I consider to be the most interesting stuttering treatment for last. Until I was 30 I stuttered so severely that I needed an hour to say what non-stutterers can say in five minutes, and then listeners couldn’t understand what I said. In 1992, after seven speech therapy programs had little or no effect on my speech, I had an MBA but was unemployed and had few friends. I changed my life from trying to overcompensate for my speech by doing everything else better than other people, to focusing on stuttering as the center of my life. I developed electronic devices that altered how I heard my voice, which made me speak fluently and trained me to speak fluently after removing the device. Now my speech is 99% better, although I still stutter mildly.
The anti-stuttering devices delay my voice to my ears a fraction of a second (delayed auditory feedback, or DAF) and shift the pitch at which I hear my voice lower (frequency-shifted auditory feedback, or FAF). When adjusted to moderate settings, DAF and FAF appear to correct a central auditory processing disorder found in brain scans of stutterers, and reduce stuttering about 70-80%. When adjusted to more extreme settings, and combined with speech therapy, the devices induce speech motor changes such as relaxed breathing, relaxed vocal folds, and a slower speaking rate. These changes can make even severe stutterers nearly 100% fluent, and continue after the devices are no longer used (“carryover fluency”). These effects can be reversed for treating speech disorders associated with Parkinson’s, which typically involve too-relaxed speech production muscles (in contrast to stutterers’ too-tense speech production muscles). It’s interesting that changing how you hear your voice has powerful effects on your brain, more powerful than medications. Perhaps some day other neurological disorders will be treated via one’s eyes, ears, or other body-centered approaches. (Eye movement desensitization and reprocessing or EMDR therapy for post-traumatic stress disorder comes to mind.)
In conclusion, stuttering and Tourette’s may have some common factors, such as abnormal dopamine utilization in specific brain areas (with Tourette’s, the putaman gross motor control area; with stuttering, the left caudate nucleus speech motor control area). Because stuttering and Tourette’s both start in early childhood, motor learning may play a role in both disorders; the stereotyped movements of a Tourette’s tic may be as hardwired as the dysfluent speech motor programs of a stutterer.
Differences include that stutterers appear to have a central auditory processing disorder, perhaps affecting how we hear our voices, when persons with Tourette’s likely have normal auditory processing. It would be interesting to see what effects, if any, DAF and FAF have on Tourette’s, tics, obsessive compulsive disorder (OCD) and attention deficit disorder (ADD). DAF and FAF only induce effects when the user is talking, but perhaps a child with ADD could focus on a math test by reading the problems aloud while wearing a DAF/FAF device? Or perhaps a person with Tourette’s or OCD could self-talk aloud when wearing a DAF/FAF device, when he or she feels the symptoms coming on. I would be happy to loan my company’s anti-stuttering devices to researchers investigating such possibilities.
For full information on the stuttering treatment devices developed by Kehoe, click here. A downloadable PDF file of his book is also available on the site, free of charge.
Thomas David Kehoe’s latest book is No Miracle Cures. He is also the author of Stuttering: Science, Therapy & Practice.
A very interesting article as, although my son never stuttered, there are cousins that did! However, where the article mentions “Differences include that stutterers appear to have a central auditory processing disorder, perhaps affecting how we hear our voices, when persons with Tourette’s likely have normal auditory processing.”….my son was diagnosed with central auditory processing disorder in PreK, some years before he had the Tourette dx.