1 - Autism's behavioral definition
A neurological basis for autism has not been
established. Therefore autism remains a psychiatric
disorder, defined by behavioral criteria. A triad of
developmental anomalies characterizes autism: (a)
impoverishment of social interaction, (b) a distinctive
disorder of communication, and (c) stereotyped
mannerisms and inflexible behaviors such as
resistance to change [1]. Failure to engage in social
interactions is thought by many people to be the
primary manifestation of autism. The social
impairment in turn is attributed to an inability to
participate in joint attention with another person or to
appreciate mental perspectives of others.
On the other hand, the distinctive disorder of
communication is the most debilitating aspect of the
triad for most parents and direct-care givers. To
refer to the communication disorder as an anomaly
and secondary to social awareness may detract from
what the center of attention should be for
rehabilitation efforts as well as research into the
neurological impairment.
Language is difficult to extinguish in the human
species. Victims of stroke retain strong traces of
language, and often struggle to make use of what is
left. The deaf use visual signs, which appear to
recruit the same areas for processing syntax involved
in understanding of spoken language [2].
Children with autism make use of phrase fragments
that they may apply to situations in contexts different
from where they were first heard; this is known as
“delayed echolalia.” Children who begin speaking in
full echolalic phrases may appear to have a better
command of language than children who speak in
baby talk. Children with high functioning autism (or
Asperger syndrome) often are late learning to speak;
but then may begin using full sentences [3]. Their
language impairment is therefore masked, and this
may be what underlies the belief that the
communication disorder is secondary to deficient
social awareness.
The idea that children with autism lack a "theory of
mind" has been widely discussed as a possible cause
for social dysfunction; this was first proposed by
Baron-Cohen et al. in 1985 [4]. Having a "theory of
mind" (ToM) means understanding that other people
have knowledge and ideas that might be useful, and
that perspectives in the minds of others are worth
consulting in formulating viewpoints beyond concrete
descriptions of how things appear to be.
Theory of mind deficits can be revealed by
experimental procedures. For example, a child is
shown a scene with a doll placing a ball behind a
chair. The child then witnesses the doll being lead
out of the room. A second (different) doll is then led
into the room and moves the ball from behind the
chair to behind the sofa. The first doll returns, and
the child is asked to show where the first doll will look
for the ball. The child lacking a theory of mind will
show the doll looking for the ball in its new location
behind the sofa, rather than where the first doll
placed the ball (behind the chair) before leaving the
room.
Acquiring a theory of mind is part of a developmental
stage, not normally reached before the age of three
or four. There are those who believe this
developmental stage is dependent upon language
development, and that a theory of mind is finally
achieved by autistic children who become proficient
in language and are then able to use linguistic based
reasoning. I agree with this, and find it difficult not to
believe the language disorder of children with autism
is primary, at least in the core syndrome described
by Kanner [5, 6].
- Wing (1997) The autistic
spectrum.
- Sakai KL et al. (2005) Sign
and speech: amodal
commonality in left
hemisphere dominance for
comprehension of sentences.
- Cederlund M, Gillberg C
(2004) One hundred males
with Asperger syndrome: a
clinical study of background
and associated factors.
- Baron-Cohen et al (1985)
Does the autistic child have a
"theory of mind"?
- Kanner (1943) Autistic
disturbances of affective
contact.
- Kanner (1946) Irrelevant and
metaphorical language early
infantile autism.
- Wing (1997) The autistic spectrum. Lancet 350:1761-1766.
- Sakai KL, Tatsuno Y, Suzuki K, Kimura H, Ichida Y. (2005) Sign and speech: amodal
commonality in left hemisphere dominance for comprehension of sentences. Brain.
2005 Jun;128(Pt 6):1407-17.
- Cederlund M, Gillberg C (2004) One hundred males with Asperger syndrome: a clinical
study of background and associated factors. Developmental Medicine & Child Neurology
46: 652-660.
- Baron-Cohen S, Leslie AM, Frith U. (1985) Does the autistic child have a "theory of mind"?
Cognition. 21:37-46.
- Kanner L (1943) Autistic disturbances of affective contact. Nervous Child 2:217-250.
Reprinted in Acta Paedopsychiatr. 1968;35(4):100-36.
- Kanner L (1946) Irrelevant and metaphorical language early infantile autism. American
Journal of Psychiatry 103:242-246. Reprinted in Am J Psychiatry. 1994 Jun;151(6 Suppl):
161-4.