The overt symptoms of stuttering sometimes cause observers to make assumptions about stuttering that are incorrect. For example, the nervousness and rapid speaking rate often seen in children who stutter is not the cause of their stuttering. Rather, it is a symptom of trying to cope with stuttering. Consequently, advice to “just relax” or “slow down” may sometimes address the behavioral symptoms of speaking, but it does not affect the stuttering itself. In other words, the nervousness and rapid rate of speech result from the fear of stuttering and being embarrassed.
Current theories point to a complicated interaction between children’s language development and their motor abilities for producing speech, combined with the multiple influences of the child’s personality and the child’s communicative and social environment. In other words, there is no single cause for stuttering, so simple explanations such as “he’s talking too fast” or “he’s nervous” do not adequately explain this complicated disorder. Recent research on a number of fronts supports this idea of stuttering as a multifactorial disorder. For example:
- Neuroimaging studies using PET scans or functional MRI to examine adults who stutter have shown different patterns of brain activation when they stutter, with more activation of right hemisphere areas and differing patterns of usage of left hemisphere, subcortical, and cerebellar structures.
- Many people who stutter perform less well on various measures of auditory processing, motor timing, integrating complex motor tasks, and some neuropsychological measures of hemispheric dominance.
- Stuttering tends to run in families, and recent research appears to indicate a genetic link for at least some individuals. Most theorists believe that a predisposition to stuttering may be heritable but its expression may be largely determined by the environment.
- Many children have concomitant problems besides stuttering, such as other speech or language development problems, learning disabilities, ADHD, etc., that may contribute to the disorder or indicate a more pervasive underlying etiological factor.
What can be said with a least some degree of empirical support is that NO single factor has been shown to be THE cause of stuttering.
- Stuttering is not caused by children’s parents
- Stuttering is not caused by drawing attention to a child’s normal disfluencies
- Stuttering is not a psychological problem (though it can have psychological consequences)
- Stuttering is not a sign of reduced intelligence, motor weakness, or neurological injury
- Stuttering is not simply a bad habit
Note: Original material provided by Larry Molt, PhD, CCC-SLP (Auburn University).