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Psychiatric Descriptions


Stuttering the medical condition is termed "developmental" stuttering to differentiate the condition from the occasional stuttering that affects us all. Developmental stuttering is an observed disruption in the normal fluency and mannerisms of speech. Fluent speech is considered to follow socially accepted time patterns, and thus stuttering is termed a "dysfluency" of speech, in that there are breaks in the flow of speech.

The dysfluency in developmental stuttering can vary widely among individuals, and most individuals who stutter tend to have a waxing and waning course of dysfluency; that is, those who stutter tend to have times when they stutter more and times when they do not. Also, stuttering usually occurs at specific points in conversation - most commonly at the beginning of sentences or phrases.

In contrast to the occasional stuttering that affects us all, the dysfluency of developmental stuttering is associated with secondary motor behaviors, such as facial and neck tics, eye blinking, lip and tongue tremors, and other body movements. Moreover, developmental stuttering is associated with a form of anxiety termed, "anticipatory anxiety."

Anticipatory anxiety is the anxiety associated with the fear of stuttering. The fear of stuttering is directly proportional to the self-perception of communication. For example, a person may stutter severely, but if he believes he is communicating well and the audience is not distracted, he has less fear and less anticipatory anxiety. In addition to the common symptoms of anxiety, anticipatory anxiety can significantly worsen the fluency and secondary motor behaviors of those who stutter. This anxiety does not cause developmental stuttering, but is rather a catalyst for dysfluency.

This constellation of dysfluency, secondary motor behaviors, and anticipatory anxiety that define developmental stuttering has been recognized since ancient Egypt. Contemporary study has revealed that one percent of the population stutters, and the condition affects every ethnicity and culture equally. Developmental stuttering affects five percent of children, typically emerging between the ages of two and six. Development stuttering may continue to adulthood, and for those children afflicted, twenty percent will continue to stutter as adults.

As mentioned earlier, anxiety does not cause developmental stuttering. Nor does a diseased tongue or overbearing parenting, as has been proposed in the past. Current study reveals that developmental stuttering is a brain-based condition that has a genetic contribution. Studies of brain function in developmental stuttering suggest that the condition is associated with variations in brain areas associated with language. Specifically, brain areas involved with formulation and expression of language, which in the vast majority of individuals are located in the dominant left cerebral hemisphere, appear to be expressed in the right hemisphere or bilaterally in those who stutter. In addition, familial and twin studies reveal a genetic component. However, a number of environmental factors may influence the emergence of developmental stuttering, and familial and twin studies of developmental stuttering reveal that the condition cannot be completely ascribed to genetics.

Interestingly, there are maneuvers that can induce fluency in persons who stutter. Singing, impersonating another's voice, speaking alone, speaking in unison with other individuals (choral speech), speaking with a metronome, auditory masking (using white noise or other masking noise to prevent those who stutter from hearing themselves speak), and delayed auditory feedback (a maneuver where an individual hears what he or she is speaking approximately two to three hundred milliseconds after he or she has spoken) all can evoke fluency. Some of these maneuvers are incorporated in treatment - and are a part of the powerful armament of treatment options for patients who stutter.