31.5 Autism Spectrum Disorder
1159
responding to verbal and nonverbal cues of a listener. Other
forms of language impairment may accompany social com-
munication disorder such as delay in learning language or
expressive and receptive difficulties. Social communication
disorder is found with greater frequency in relatives of indi-
viduals with autism spectrum disorder, which increases the
difficulty in discriminating this disorder from autism spectrum
disorder. Although relationships may be negatively affected by
social communication disorder, this disorder does not include
restricted or repetitive behaviors and interests, as autism spec-
trum disorder does.
Childhood Onset Schizophrenia
Schizophrenia is rare in children younger than 12 years and
almost nonexistent before the age of 5 years. Characterized by
hallucinations or delusions, childhood onset schizophrenia has
a lower incidence of seizures and intellectual disability and poor
social skills. Table 31.5-2 compares autism spectrum disorder
and schizophrenia with childhood onset.
Intellectual disabilitywithBehavioral Symptoms
Children with intellectual disability may exhibit behavioral
symptoms that overlap with some autism spectrum disorder
features. The main differentiating features between autism
spectrum disorder and intellectual disability are that children
with intellectual disability syndromes generally display global
impairments in both verbal and nonverbal areas, whereas chil-
dren with autism spectrum disorder are relatively weak in social
interactions compared to other areas of performance. Children
with intellectual disability generally relate verbally and socially
to adults and peers in accordance with their mental age, and they
exhibit a relatively even profile of limitations.
Language Disorder
Some children with language disorders also have autism spec-
trum disorder features, which may present a diagnostic chal-
lenge. Table 31.5-3 summarizes the major differences between
autism spectrum disorder and language disorders.
Table 31.5-2
Autism Spectrum Disorder versus Childhood Onset Schizophrenia
Criteria
Autism Spectrum Disorder
Schizophrenia (with Onset before Puberty)
Age of onset
Early developmental period
Rarely under 5 years of age
Incidence
1 percent
<
1 in 10,000
Sex ratio (M:F)
4:1
1.67:1 (slight preponderance of males)
Family history of schizophrenia Not increased
Likely Increased
Prenatal and perinatal
complications
Increased
Not increased
Behavioral characteristics
Poor social relatedness; may have aberrant language,
speech or echolalia; stereotyped phrases; may have
stereotypies, repetitive behaviors
Hallucinations and delusions; thought
disorder
Adaptive functioning
impaired
Deterioration in functioning
Level of intelligence
Wide range, may be intellectually disabled
(30 percent)
Usually within normal range, may be low
average normal
Pattern of IQ
Typical higher performance than verbal
More even
Grand mal seizures
4 percent to 32 percent
low incidence
(Adapted from Magda Campbell, M.D., and Wayne Green, M.D.)
Table 31.5-3
Autism Spectrum Disorder versus Language Disorder
Criteria
Autism Spectrum Disorder
Language Disorder
Incidence
1 percent
5 of 10,000
Sex ratio (M:F)
4:1
Equal or almost equal sex ratio
Family history of speech delay or
language problems
<
25 percent of cases
<
25 percent of cases
Associated deafness
Very infrequent
Not infrequent
Nonverbal communication (e.g., gestures)
Impaired
Actively utilized
Language abnormalities (e.g., echolalia,
stereotyped phrases out of context)
Present in a subset
Uncommon
Articulation problems
Infrequent
frequent
Intellectual level
Impaired in a subset (about 30 percent)
Uncommon, less frequently severe
Patterns of intelligence quotient (IQ) tests Typically lower on verbal scores than
performance scores;
Often verbal scores lower than performance
scores
Impaired social communication,
restricted and repetitive behaviors,
Present
Absent or, if present, mild
Imaginative play
Often impaired
Usually in tact
(Adapted from Magda Campbell, M.D., and Wayne Green, M.D.)
