Autism is a lifelong
developmental disorder that affects the
way a person communicates and relates to
people around them. In the great majority
of cases, autistic disorders are present
from birth or become apparent within the
first three years of life. The best-known
types of autism are ‘typical autism’
and Asperger’s syndrome. People with
typical autism have no interest in social
interaction, little or no language, and
tend to live in their own world. Asperger’s
syndrome often applies to those who are
more able, who have better language development,
and who have more social contact.
The condition of autism
was first described in 1943 by the American
child psychologist Leo Kanner. Today, although
its exact nature and causes remain unknown,
autism is now generally recognised to be
a neurological disorder in the brain, possibly
of genetic origin.
The age at which autism
begins is unknown, but it is nearly always
recognised that something is wrong before
the age of 30 months, sometimes as early
as 12 months. It affects about 1 child in
2500. Boys are affected four times as often
as girls are.
Autism causes behavioural
patterns that can be deeply distressing
to all concerned. It is of variable severity
and takes different forms, ranging from
a complete withdrawal from all social relationships
and a total inability to use language meaningfully,
to a much milder form of isolationism.
Asperger’s syndrome
is a condition similar to, but usually less
severe than autism, that affects about 1–2
persons in 1000, males more often than females.
Affected people, who are normally intelligent,
may be physically clumsy, may have unusually
narrow interests bordering on obsessional
behaviour, and may have difficulty in managing
social relationships.
In autism, the outlook
is best for those children who are able
to speak and to respond. Some of these can
recover apparently fully. For children who
remain mute after the age of five, the outlook
is not as good.
Causes
The causes of autism
are not clear. Around 10% relate to a specific
medical condition or infection but the remaining
90% have no known cause. Genetic factors
are of major importance but other physical
conditions affecting development of the
brain, before, during or after birth may
also be involved. The condition tends to
run in families, and if one of a pair of
identical twins is affected the other has
a 90–95 per cent chance of also being
affected. Brothers and sisters of an autistic
child are about twice as likely to be autistic
as children from families without such a
child. All this suggests that a genetic
cause is involved.
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Autism
