There is nothing wrong with stammerer' tongues, vocal folds
or breathing. Stammreres are not more nervous, do not necessarily
have worse self-esteem, and are as likely to be intelligent and
well-adjusted as non-stammerer.
Stammering is a developmental disorder. Some experts believe
that stammering develops from the normal mistakes all children make
when learning to talk. While most children can pick themselves up
after a stumble, some children get into a vicious cycle of trying
harder to talk, tensing their speech production muscles too much,
and getting more stuck.
Other experts have found that severe stammering can develop
almost overnight in young children. They believe that stammering may
not develop gradually from normal disfluencies or language
difficulties. Genes have been found associated with stammering, so
some experts believe that a genetic defect causes something in the
child's brain to trigger stammering.
Although the origin of stammering is not clear,
everyone agrees that childhood stuttering can develop into a severe
physical and psychological disability. Adults who stammer can have
physical symptoms, including:
Breathing abnormalities during stuttering, especially upper
Laryngeal blocks, which cut off airflow during stammering.
Articulation problems, including tension in the lips, jaw
and tongue, and prolonged or repeated sounds.
Secondary or 'escape' behaviours, such as twitching, head
jerks, eye blinking, or facial grimaces.
The psychological symptoms of adult stammrer
Avoidance of feared sounds, words, and speaking situations.
For example, the stammerer may avoid making telephone calls.
Substitution of another word.
'Anti-expectancy' speech behaviours to prevent stuttering
such as speaking in a monotone, or affecting an accent.
Some stutterers are so good at avoidance that their
co-workers and even their spouse or family don't know that the
individual stammer. Even though their speech sounds fine, these
'covert' stammrer can be crippled by severe psychological fear and