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Chapter 31: Child Psychiatry
blinks, facial grimacing, head jerks, and abnormal body move-
ments, may be observed before or during the disrupted speech.
Early intervention is important because children who receive
early intervention have been found to be more than 7 times more
likely to have full resolution of their stuttering. In severe and
some untreated cases, stuttering can become an entrenched pat-
tern that is more challenging to remediate later in life and is
associated with significant psychological and social distress.
When stuttering becomes chronic, persisting into adulthood, the
rates of concurrent social anxiety disorder are reported to be
between 40 and 60 percent.
Epidemiology
An epidemiologic survey of 3- to 17-year-olds derived from
the United States National Health Interview Surveys reports
that the prevalence of stuttering is approximately 1.6 percent.
Stuttering tends to be most common in young children and has
often resolved spontaneously by the time the child is older. The
typical age of onset is 2 to 7 years of age, with 90 percent of
children exhibiting symptoms by age 7 years. Approximately
65 to 80 percent of young children who stutter are likely to have
a spontaneous remission over time. According to the DSM-5,
the rate dips to 0.8 percent by adolescence. Stuttering affects
about three to four males for every one female. The disorder is
significantly more common among family members of affected
children than in the general population. Reports suggest that for
male persons who stutter, 20 percent of their male children and
10 percent of their female children will also stutter.
Comorbidity
Very young children who stutter typically show some delay in
the development of language and articulation without additional
disorders of speech and language. Preschoolers and school-age
children who stutter exhibit an increased incidence of social
anxiety, school refusal, and other anxiety symptoms. Older chil-
dren who stutter also do not necessarily have comorbid speech
and language disorders, but often manifest anxiety symptoms
and disorders. When stuttering persists into adolescence, social
isolation occurs at higher rates than in the general adolescent
population. Stuttering is also associated with a variety of abnor-
mal motor movements, upper body tics, and facial grimaces.
Other disorders that coexist with stuttering include phonologi-
cal disorder, expressive language disorder, mixed receptive–
expressive language disorder, and ADHD.
Etiology
Converging evidence indicates that cause of stuttering is multi-
factorial, including genetic, neurophysiological, and psycholog-
ical factors that predispose a child to have poor speech fluency.
Although research evidence does not indicate that anxiety or
conflicts cause stuttering or that persons who stutter have more
psychiatric disturbances than those with other forms of speech
and language disorders, stuttering can be exacerbated by certain
stressful situations.
Other theories about the cause of stuttering include organic
models and learning models. Organic models include those that
focus on incomplete lateralization or abnormal cerebral domi-
nance. Several studies using EEG found that stuttering males
had right hemispheric alpha suppression across stimulus words
and tasks; nonstutterers had left hemispheric suppression. Some
studies of stutterers have noted an overrepresentation of left-hand-
edness and ambidexterity. Twin studies and striking gender differ-
ences in stuttering indicate that stuttering has some genetic basis.
Learning theories about the cause of stuttering include the
semantogenic theory, in which stuttering is basically a learned
response to normative early childhood disfluencies. Another
learning model focuses on classic conditioning, in which the
stuttering becomes conditioned to environmental factors. In the
cybernetic model, speech is viewed as a process that depends on
appropriate feedback for regulation; stuttering is hypothesized
to occur because of a breakdown in the feedback loop. The
observations that stuttering is reduced by white noise and that
delayed auditory feedback produces stuttering in normal speak-
ers lend support to the feedback theory.
The motor functioning of some children who stutter appears
to be delayed or slightly abnormal. The observation of difficul-
ties in speech planning exhibited by some children who stutter
suggests that higher-level cognitive dysfunction may contribute
to stuttering. Although children who stutter do not routinely
exhibit other speech and language disorders, family members of
these children often exhibit an increased incidence of a variety
of speech and language disorders. Stuttering is most likely to be
caused by a set of interacting variables that include both genetic
and environmental factors.
Diagnosis
The diagnosis of childhood-onset fluency disorder (stuttering)
is not difficult when the clinical features are apparent and well
developed and each of the following four phases (described in the
next section) are readily recognized. Diagnostic difficulties can
arise when evaluating for stuttering in young children, because
some preschool children experience transient dysfluency. It may
not be clear whether the nonfluent pattern is part of normal
speech and language development or whether it represents the
initial stage in the development of stuttering. If incipient stut-
tering is suspected, referral to a speech pathologist is indicated.
Clinical Features
Stuttering usually appears between the ages of 18 months and
9 years, with two sharp peaks of onset between the ages of 2 to
3.5 years and 5 to 7 years. Some, but not all, stutterers have
other speech and language problems, such as phonological
disorder and expressive language disorder. Stuttering does not
begin suddenly; it typically develops over weeks or months with
a repetition of initial consonants, whole words that are usually
the first words of a phrase, or long words. As the disorder pro-
gresses, the repetitions become more frequent, with consistent
stuttering on the most important words or phrases. Even after it
develops, stuttering may be absent during oral readings, singing,
and talking to pets or inanimate objects.
Four gradually evolving phases in the development of stut-
tering have been identified:
00
Phase 1
occurs during the preschool period. Initially, the dif-
ficulty tends to be episodic and appears for weeks or months
between long interludes of normal speech. A high percent-
age of recovery from these periods of stuttering occurs.
