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| Definitions of
Autism |
Definitions and descriptions of autism abound, many of them
overlapping in parts or emphasis depending on the purposes for which
they are promulgated. It is useful and instructive to compare the
definitions from the medical/diagnostic perspective, from the
etiological and neurobiological perspective, and from the point of view
of advocacy and societal issues. Together
these complementary viewpoints increase our understanding and hence
inform our practices.
Definition from the Diagnostic and Statistic Manual -
fourth edition (DSM-IV)
The DSM-IV, the Diagnostic and Statistical Manual of the American
Psychiatric Association, published in 1996, defines autism as a set of
behavioral characteristics for the purpose of defining diagnostic
criteria to differentiate this disorder from others. Under the broad
heading of Pervasive Developmental Disorders (not in itself a diagnostic
category), criteria are established to diagnose Autistic Disorder,
Rett’s Disorder, Aspergers' Disorder, Childhood Disintegrative
Disorder, and PDD-NOS (Pervasive Developmental Disorder- Not Otherwise
Specified). These disorders are diagnosed as "syndromes",
meaning that diagnosis is based on the presence of certain types of
behaviors occurring together without any assumptions being made about
etiological or causal agents. (The specific genetic defect responsible
for Rett's Disorder has recently been identified.)
The diagnostic criteria in DSM-IV for
Autistic Disorder and for Aspergers’ Disorder follow.
Diagnostic criteria
for 299.00 Autistic Disorder
A.
A total of six (or more) items from (1), (2), and (3), with at least
two from (1), and one each from (2) and (3):
(1)
qualitative impairment in social interaction, as manifested by at
least two of the following:
(a) marked
impairment in the use of multiple nonverbal
behaviors such as
eye-to-eye gaze, facial expression, body postures, and gestures to
regulate social interaction
(b) failure
to develop peer relationships appropriate to developmental level
(c) a
lack of spontaneous seeking to share enjoyment, interests, or
achievements with other people (e.g., by a lack of showing,
bringing, or pointing out objects of interest)
(d) lack
of social or emotional reciprocity
(2) qualitative
impairments in communication as manifested by at least one of the
following:
(a) delay
in, or total lack of, the development of spoken language
(not accompanied by an attempt to compensate through alternative
modes of communication such as gesture or mime)
(b) in
individuals with adequate speech, marked impairment in the ability
to initiate or sustain a conversation with others
(c) stereotyped
and repetitive use of language or idiosyncratic language
(d) lack
of varied, spontaneous make-believe play or social imitative play
appropriate to developmental level
(3) restricted
repetitive and stereotyped patterns of behavior, interests, and
activities, as manifested by at least one of the following:
(a) encompassing
preoccupation with one or more stereotyped and restricted patterns
of interest that is abnormal either in intensity or focus
(b) apparently
inflexible adherence to specific, nonfunctional routines or rituals
(c) stereotyped
and repetitive motor mannerisms (e.g., hand or finger flapping or
twisting, or complex whole-body movements)
(d) persistent
preoccupation with parts of objects
B.
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.
C.
The disturbance is not better
accounted for by Rett's Disorder or Childhood Disintegrative
Disorder.
Diagnostic criteria
for 299.80 Asperger's Disorder
A.
Qualitative impairment in social
interaction, as manifested by at least two of the following:
(1) marked
impairment in the use of multiple nonverbal behaviors such as
eye-to-eye gaze, facial expression, body postures, and gestures to
regulate social interaction
(2) failure
to develop peer relationships appropriate to developmental level
(3) a
lack of spontaneous seeking to share enjoyment, interests, or
achievements with other people (e.g., by a lack of showing,
bringing, or pointing out objects of interest to other people)
(4) a
lack of social or emotional reciprocity
B.
Restricted repetitive and
stereotyped patterns of behavior, interests, and activities, as
manifested by at least one of the following:
(1) encompassing
preoccupation with one or more stereotyped and restricted patterns
of interest that is abnormal either in intensity or focus
(2) apparently
inflexible adherence to specific, nonfunctional routines or rituals
(3) stereotyped
and repetitive motor mannerisms (e.g., hand or finger flopping or
twisting, or complex whole-body movements)
(4) persistent
preoccupation with parts of objects
C.
The disturbance causes
clinically significant impairment in social, occupational, or other
important areas of functioning.
D.
There is no clinically
significant general delay in language (e.g., single words used by
age 2 years, communicative phrases used by age 3 years).
E.
There is no clinically
significant delay in cognitive development or in the development of
age-appropriate self-help skills, adaptive behavior (other than in
social interaction), and curiosity about the environment in
childhood.
F.
Criteria are not met for another
specific Pervasive Developmental Disorder or Schizophrenia.
Definition & Description from Neurobiology
of Autism by Isabelle Rapin, MD & Rober Katzman, MD (1998)
Researchers have now established that autism is a biological disorder
but much more investigation is needed for the specific underlying bases
and mechanisms to be unraveled. In their book, Neurobiology of Autism
(1998), Rapin and Katzman state, "Autism is a lifelong condition,
manifest from very early childhood. It denotes deviant brain development
with genetic implications and represents a major public health problem
because it often requires lifelong societal support."
Rapin and Katzman define the clinical features of autism in a way
consistent with that of DSM-IV but also note deficits in cognition in a
high proportion of cases. They further suggest that autism has a wide
range of severity, hypothesizing, as have others, that Aspergers’
Disorder may represent the mild end of the autism spectrum. Their
clinical description emphasizes several important features. They
particularly note the "young children’s reduced ability to focus
attention with another person on a common target or activity (and) play
(which) is grossly defective, unimaginative, manipulative, and
solitary." Despite hyper focus in idiosyncratic ways, these
children also may be severely hyperactive and disorganized, especially
in unstructured situations.
These authors emphasize that the evidence so far is suggestive but
non-specific regarding the neurobiology underling autism. "Autism
is a behaviorally defined syndrome with a complex etiology and little is
known about its pathological basis. … In a minority of cases, autism
may be associated with readily diagnosable genetic and nongenetic
conditions. … Epidemiological evidence indicates that environmental
factors such as perinatal insults play a minor etiological role.
Genetics or genetic vulnerability to some environmental factors may be
prepotent in most cases of unknown cause. … Coherent chemical
understanding and rational pharmacology is only now beginning to emerge.
" Similarly the neurological basis for the characteristic motor
manifestations as well as for autism’s many sensory aberrations is
unknown at this time. However, despite these reservations, the authors
make clear that current research into the brain from anatomical,
chemical, pathological and developmental perspectives are suggestive and
promising.
Definition by Autism Society of America (1999)
The Autism Society of America has recently published their new
description of autism as a way to clarify and summarize current opinion.
Their concise statement covers diagnostic, behavioral, epidemiological,
and neurological aspects in an easily accessible format. Their statement
follows:
Autism is a complex developmental disability that typically appears
during the first three years of life. The
result of a neurological disorder that affects the functioning of the
brain, autism, and its associated behaviors have been estimated to
occur in as many as 1 in 500 individuals (Centers for Disease Control
and Prevention 1997). Autism
is four times more prevalent in boys than girls and knows no racial,
ethnic, or social boundaries. Family
income, lifestyle, and educational levels do not affect the chance of
autism's occurrence.
Autism impacts the normal development of the brain in the areas of
social interaction and communication skills. Children
and adults with autism typically have difficulties in verbal and
non-verbal communication, social interactions, and leisure or play
activities. The
disorder makes it hard for them to communicate with others and relate
to the outside world. In
some cases, aggressive and/or self-injurious behavior may be present.
Persons with autism may exhibit
repeated body movements (hand flapping, rocking), unusual responses to
people or attachments to objects and resistance to changes in
routines. Individuals
may also experience sensitivities in the five senses of sight,
hearing, touch, smell, and taste.
Over one half million people in the U.S. today have autism or some
form of pervasive developmental disorder. Its
prevalence rate makes autism one of the most common developmental
disabilities. Yet
most of the public, including many professionals in the medical,
educational, and vocational fields, are still unaware of how autism
affects people and who they can effectively work with individuals with
autism.
Several related disorders are grouped under the broad heading
"Pervasive Developmental Disorder" or PDD-a general category
of disorders which are characterized by severe and pervasive
impairment in several areas of development (American Psychiatric
Association 1994). A
standard reference is the Diagnostic and Statistical Manual (DSM), a
diagnostic handbook now in its fourth edition.
The DSM-IV lists criteria to be met
for a specific diagnosis under the category of Pervasive Developmental
Disorder. Diagnosis
is made when a specified number of characteristics listed in the
DSM-IV are present. Diagnostic
evaluations are based on the presence of specific behaviors indicated
by observation and through parent consultation, and should be made by
an experienced, highly trained team. Thus,
when professionals or parents are referring to different types of
autism, often they are distinguishing autism from one of the other
pervasive developmental disorders. (Autism
Society of America 1999)
This is a useful statement but the limitation of this format is that
controversy and contradictory evidence is insufficiently explicated. In
particular, the areas of the brain controlling "social interaction
and communication skills" have not yet been clearly and
unambiguously established and the evidence to support these hypotheses
is still being developed.
Implications for Education
These three approaches (diagnosis, research, advocacy) together can
provide a useful working definition of autism for educational purposes.
Autism is the result of as yet unspecified impairments to normal brain
development from potentially multiple and variably overlapping causes.
The syndrome that results has certain general features, categorized into
three groups for diagnostic purposes, but also many other regularly
associated features which impact functioning and must be addressed
educationally. In broad terms, the most striking of these
characteristics are in the domains of cognitive functioning, including
intellectual attainment as well as the capacity for imagination and
play, sensory sensitivity, hyperactivity, the regulation of anxiety,
attentional focus, and the expression of motivation, initiative, and
persistence.
The implication of such multiple and variable difficulties for the
educational process is that the child’s total environment must be
educationally sound and supportive in order to create conditions under
which the child can learn. It must also be remembered, and be
incorporated into the educational philosophy, that the
"autism" does not define the child and is only a part of the
child. All of the child’s needs …, to be nurtured, to be stimulated
intellectually and aesthetically, to feel safe and secure and
self-confident in having success and mastery, to have the health created
by having an appropriate rhythm of daily life and the development of
physical stamina, strength and coordination, to relate to others and be
a part of and contribute to their communities, to communicate their
needs and wants, to have independence and dignity and to respect others
and be treated with respect … must be addressed in a broad and
age-appropriate curriculum as is the case for any typical as well as any
autistic child.
(This
page is quoted from the Home Page
of Boston Higashi School.)
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