Kaplan + Sadock's Synopsis of Psychiatry, 11e

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Chapter 31: Child Psychiatry

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.

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