642 CHAPTER 14
the girl’s head slows and she loses the ability to control normal muscle movements,
interest in other people, and previously developed skills. The skills that are lost
include the voluntary movement of hands (which is replaced by recurrent hand ges-
tures that resemble hand-washing or hand-wringing) and coordination of the trunk.
In addition to the loss of skills, a girl with Rett’s disorder has language problems
and psychomotor retardation. Mental retardation is an inevitable consequence of
this disorder.
Although Rett’s disorder includes some of the problems in communicating that
mark autism and childhood disintegrative disorder, it has three unique features: a
slowed rate of growth of the child’s head circumference, coordination problems, and
the loss of hand skills. Moreover, symptoms of Rett’s disorder emerge by 2 years of
age, at the latest; childhood disintegrative disorder symptoms emerge between 2
and 10. Rett’s disorder occurs only in females because it is an X-linked genetic dis-
order that impedes normal brain development related to movement and cognition
(Amir et al., 1999; Matijevic et al., 2009). Male fetuses with this mutation typically
do not survive until birth.Key Concepts and Facts About Pervasive Developmental Disorders
- Pervasive developmental disorders involve two types of prob-
lems: (1) signifi cant defi cits in communication and social inter-
action skills, and (2) stereotyped behaviors or narrow interests.
Disorders in this category are autistic disorder, Asperger’s disor-
der, childhood disintegrative disorder, and Rett’s disorder. - Autistic disorder (or simply, autism) is characterized by signifi -
cant problems with communication, social interactions, and lan-
guage use. Individuals with autism are oblivious to other people
and do not pay attention to or understand basic social rules and
cues. They may have extremely narrow interests involving repet-
itive play. Many people with autism also have comorbid mental
retardation when tested with conventional intelligence tests; on
tests that do not rely on verbal abilities, however, people with
autism tend to score in the average range or higher. In addition,
some people with autism have unique skills. - Asperger’s disorder is characterized by problems that are simi-
lar to—though less severe than—those associated with autism.
With Asperger’s, however, language and cognitive development
are in the normal range. People with Asperger’s avoid eye con-
tact and are often unaware of other people’s responses. They
may be interested in social relationships but because they do
not generally understand conventional social rules, forming and
maintaining relationships is diffi cult. - Neurological factors that underlie autism include abnormal con-
nections and communication among different brain areas, in
particular, between the frontal lobe and the rest of the brain.
Genes play a role in the development of autism and Asperger’s. - Psychological symptoms of autism include defi cits in shifting at-
tention and in mental fl exibility, and an impaired theory of mind.
People with Asperger’s have less severe problems in using a
theory of mind than do people with autism. Social symptoms of
autism include problems in recognizing emotion in the voices or
faces of others and in understanding the give and take of social
communication.- Interventions for autism include medication for comorbid disor-
ders or symptoms of anxiety, agitation, and aggression. Medi-
cation is not usually prescribed for symptoms of Asperger’s
disorder. Treatment for autism that targets psychological factors
includes applied behavior analysis to modify maladaptive be-
haviors. Treatments that target psychological and social factors
focus on teaching the individual to communicate, to recognize
conventional social cues, and to read the emotional expres-
sions of others, as well as how to initiate and respond in social
situations. - In contrast to autism and Asperger’s disorder, childhood disin-
tegrative disorder is characterized by normal development up to
at least 2 years of age, followed by a profound loss of communi-
cation skills, normal types of play, and bowel control. - Rett’s disorder also involves the loss of skills already mastered,
but the onset of the disorder occurs between 5 months and
2 years of age. The child loses interest in other people and the
ability to control normal muscle movements. Mental retardation
always accompanies Rett’s disorder, which affects only females.
- Interventions for autism include medication for comorbid disor-
Making a Diagnosis
- Reread Case 14.2 about James, and determine whether or not
his symptoms meet the criteria for autism. Specifically, list
which criteria apply and which do not. If you would like more
information to determine his diagnosis, what information—
specifi cally—would you want, and in what ways would the infor-
mation infl uence your decision? - Reread Case 14.3 about Josh, and determine whether or not his
symptoms meet the criteria for Asperger’s disorder. Specifi cally,
list which criteria apply and which do not. If you would like more
information to determine his diagnosis, what information—
specifi cally—would you want, and in what ways would the infor-
mation infl uence your decision?