Types of Autism
Like many things you can't lump all
Autistic people in the same category, as there are different
types of autism. Autism presents in a wide degree, from those
who are nearly dysfunctional and apparently mentally
handicapped to those whose symptoms are mild or remedied enough
to appear unexceptional ("normal") to others.
Although not used or accepted by professionals or within the
literature, autistic individuals are often divided into those
with an IQ<80 referred to as having "low-functioning autism"
(LFA), while those with IQ>80 are referred to as having
"high-functioning autism" (HFA). Low and high functioning are
more generally applied to how well an individual can accomplish
activities of daily living, rather than to IQ. The terms low
and high functioning are controversial and not all autistics
accept these labels.
This discrepancy can lead to confusion among service
providers who equate IQ with functioning and may refuse to
serve high-IQ autistic people who are severely compromised in
their ability to perform daily living tasks, or may fail to
recognize the intellectual potential of many autistic people
who are considered LFA. For example, some professionals refuse
to recognize autistics who can speak or write as being autistic
at all, because they still think of autism as a communication
disorder so severe that no speech or writing is possible.
As a consequence, many "high-functioning" autistic persons,
and autistic people with a relatively high IQ, are
underdiagnosed, thus making the claim that "autism implies
retardation" self-fulfilling. The number of people diagnosed
with LFA is not rising quite as sharply as HFA, indicating that
at least part of the explanation for the apparent rise is
probably better diagnostics. Many also think that ASD's are
being over diagnosed, due to the spectrum quality of the
impairments and the desire to obtain services through schools
and therapies.
Asperger's and Kanner's syndrome
In the current Diagnostic and Statistical Manual of Mental
Disorders (DSM-IV-TR), the most significant difference between
Autistic Disorder (Kanner's) and Asperger's syndrome is that a
diagnosis of the former includes the observation of "delays or
abnormal functioning in at least one of the following areas,
with onset prior to age 3 years: (1) social interaction, (2)
language as used in social communication, or (3) symbolic or
imaginative play" , while a diagnosis of Asperger's syndrome
observes "no clinically significant delay" in these areas.
Whilst the DSM-IV does not include level of intellectual
functioning in the diagnosis, the fact that those with
Asperger's syndrome tend to perform better than those with
Kanner's autism has produced a popular conception that
Asperger's syndrome is synonymous with "higher-functioning
autism," or that it is a lesser disorder than autism.
Similarly, there is a popular conception that autistic
individuals with a high level of intellectual functioning in
fact have Asperger's syndrome, or that both types are merely
'geeks' with a medical label attached.
The popular depiction of autism in the media has been of
relatively severe cases, for example, as seen in the films Rain
Man (autistic adult) and Mercury Rising (autistic child), and
in turn many relatives of those who have been diagnosed in the
autistic spectrum choose to speak of their loved ones as having
Asperger's syndrome rather than autism.
Autism as a spectrum disorder
Another view of these disorders is that they are on a continuum
known as autistic spectrum disorders. A related continuum,
Sensory Integration Dysfunction, involves how well humans
integrate the information we receive from our senses. Autism,
Asperger's syndrome, and Sensory Integration Dysfunction are
all closely related and overlap.
Some people believe that there might be two manifestations
of classical autism, regressive autism and early infantile
autism. Early infantile autism is present at birth while
regressive autism begins before the age of 3 and often around
18 months. Although this causes some controversy over when the
neurological differences involved in autism truly begin, some
speculate that an environmental influence or toxin triggers the
disorder. This triggering could occur during gestation due to a
toxin that enters the mother's body and is transferred to the
fetus. The triggering could also occur after birth during the
crucial early nervous system development of the child.
From Wikipedia, the free encyclopedia
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