2.
THE PDD CATEGORY AND ITS FIVE SPECIFIC DISORDERS
TYPE
1) AUTISTIC DISORDER: Autistic
Disorder, sometimes referred to as early infantile autism
or childhood autism, is four times more common in boys than
in girls. Children with Autistic Disorder have a moderate
to severe range of communication, socialization, and behavior
problems. Many children with autism also have mental retardation.
The DSM-IV criteria by which Autistic Disorder is diagnosed
are presented below.
TYPE
2) RETT'S DISORDER: Rett's Disorder, also
known as Rett Syndrome, is diagnosed primarily in females.
In children with Rett's Disorder, development proceeds in
an apparently normal fashion over the first 6 to 18 months
at which point parents notice a change in their child's
behavior and some regression or loss of abilities, especially
in gross motor skills such as walking and moving. This is
followed by an obvious loss in abilities such as speech,
reasoning, and hand use. The repetition of certain meaningless
gestures or movements is an important clue to diagnosing
Rett's Disorder; these gestures typically consist of constant
hand-wringing or hand-washing (Moeschler, Gibbs, & Graham
1990). The diagnostic criteria for Rett's Disorder as set
forth in the DSM-IV appear below.
TYPE
3) CHILDHOOD DISINTEGRATIVE DISORDER: Childhood
Disintegrative Disorder, an extremely rare disorder, is
a clearly apparent regression in multiple areas of functioning
(such as the ability to move, bladder and bowel control,
and social and language skills) following a period of at
least 2 years of apparently normal development. By definition,
Childhood Disintegrative Disorder can only be diagnosed
if the symptoms are preceded by at least 2 years of normal
development and the onset of decline is prior to age 10
(American Psychiatric Association, 1994). DSM-IV criteria
are presented below.
TYPE 4) ASPERGER'S DISORDER: Asperger's
Disorder, also referred to as Asperger's or Asperger's Syndrome,
is a developmental disorder characterized by a lack of social
skills; difficulty with social relationships; poor coordination
and poor concentration; and a restricted range of interests,
but normal intelligence and adequate language skills in
the areas of vocabulary and grammar. Asperger's Disorder
appears to have a somewhat later onset than Autistic Disorder,
or at least is recognized later. An individual with Asperger's
Disorder does not possess a significant delay in language
development; however, he or she may have difficulty understanding
the subtleties used in conversation, such as irony and humor.
Also, while many individuals with autism have mental retardation,
a person with Asperger's possesses an average to above average
intelligence (Autism Society of America, 1995). Asperger's
is sometimes incorrectly referred to as "high-functioning
autism." The diagnostic criteria for Asperger's Disorder
as set forth in the DSM-IV are presented below.
TYPES OF PDD: 5) PERVASIVE DEVELOPMENTAL DISORDER NOT OTHERWISE
SPECIFIED: Children with
PDDNOS either (a) do not fully meet the criteria of symptoms
clinicians use to diagnose any of the four specific types
of PDD above, and/or (b) do not have the degree of impairment
described in any of the above four PDD specific types.
