What is Autism?
by Dr Avril Brereton
Autism is a syndrome consisting of a set of developmental and
behavioural features. The core features of autism include impairments
in three main areas of functioning:
· social
interaction,
· communication,
· restricted,
repetitive and stereotyped patterns of behaviour, interests and
activities.
Autism affects the person throughout life.
How does autism affect children?
1. Social interaction
One of the key
features of autism is abnormal interpersonal relationships. Children
with autism often show a reduced responsiveness to or interest in
people, an appearance of aloofness and a limited or impaired ability to
relate to others. Children with autism usually show very little
variation in facial expression, have abnormal eye contact and tend not
to engage in social imitation, such as waving bye-bye and pat-a-cake
games. They rarely develop age-appropriate empathy or the ability to
understand that other people have feelings. Although children with
autism do develop some social relating skills, these skills are usually
restricted or abnormal. Their ability to make friends is absent or
distorted and they are usually unable to play reciprocally with other
children.
2. Communication
Children with
autism usually have quite delayed and unusual speech. Approximately 50%
of children with autism will eventually have useful speech. Children
with autism also have an impaired ability to use gesture.
In those children
who do develop language, the tone, pitch and modulation of speech is
often odd and the voice may sound mechanical or flat in quality. Some
children speak in whispers or too loudly and some speak in an unusual
accent. Echolalia, the immediate repetition of what has just been said
or the delayed repetition of phrases, is common. Some children repeat
advertising jingles or large pieces of dialogue from videos, perhaps
days later, for no apparent reason. Their understanding of spoken
language is often literal and they do not understand metaphors such as “
shake a leg”.
Some children with
autism develop a wide vocabulary and expressive verbal skills, however,
even they have difficulty with the pragmatic or social use of language.
They have impaired ability to initiate conversation and maintain the “to
and fro” of a conversation.
3. Ritualistic and Stereotyped Interests or Behaviours
Ritualistic and
compulsive behaviours are common, such as lining up toys and having
rigid routines for daily activities. There is often a resistance to
change in routine or the environment so that the child may become
extremely distressed if a new route is taken to school, furniture in the
house is rearranged or the child is asked to wear new clothes.
Hand and finger
mannerisms and repetitive body movements, such as hand flapping or
tip-toe walking, are common. There is often a fascination with movement
of objects, such as spinning wheels. Children may look closely at the
fine detail of an object such as the edge of a table or spokes on a
wheel, or collect objects such as buttons or twigs. Many children with
autism, especially in middle to late childhood, have unusual
pre-occupations that they follow to the exclusion of other activities.
These may involve a fascination with bus routes or train timetables in
association with repeatedly asking questions to which specific answers
must be given.
4. Play and Imagination
Children with
autism usually have rigid and limited play, with a noticeable lack of
imagination and creativity. They may repetitively line up toys, sort by
colour, or collect various objects such as pieces of string or objects
of a certain colour or shape. Intense attachment to these objects can
occur with the child showing great distress if these objects are taken
away or the patterns are disrupted.
Older children may
develop play that superficially appears to be creative, such as
re-enacting the day at school with dolls or acting out scenes from
favourite videos. Observation of this type of play over time often
reveals a highly repetitive scenario that does not change and cannot be
interrupted.
Children with
autism rarely involve other children in their play, unless they are
given a particular role in a situation in which the autistic child is in
control and makes the rules.
5. Associated features
Many other
abnormalities are associated with autism, such as unusual dietary
habits, sleep disturbance, abnormalities of mood and self-injurious
behaviour. Perceptual abnormalities such as lack of response to pain,
heightened sensitivity to sound and preoccupation with tactile
stimulation are also common. These features are not specific to
individuals with autism and may occur in other children with
intellectual disability.
6. Intellectual ability
The majority of
children with autism have intellectual disability. A recent review of
the literature found that in most samples approximately 50% of cases
exhibit severe intellectual disability, 30% mild to moderate disability
and the remaining 20% have IQ’s in the normal range.
What causes Autism?
The exact causes
of Autism are unknown. We do know that it is a biological condition
that children are born with. Genetic factors play an important role in
the causation of autism, although which genes are involved has not been
determined. People with autism probably share certain features of
abnormal brain function, but the nature of these remains elusive and
controversial.
How common is autism?
Recent international research (Chakrabarti
and Fombonne, 2005) now suggests that the best estimate for the
prevalence of all autism spectrum disorders is 60 per 10,000
population. A three year study commissioned by the Australian Advisory
Board on Autism Spectrum Disorders into the prevalence of autism,
concluded that there is a prevalence of 62.5 per 10,000 or one in 160
Australian children aged between 6 and 12 years have an autism spectrum
disorder (ASD) (Wray and Williams, 2007).
References
Chakrabarti, S., Fombonne, E. (2005)
Pervasive Developmental Disorders in Pre-school aged children.
Confirmation of High Prevalence. A. J. Psychiat. 162: 1133-1144
Wray, J., Williams, K. (2007) The
Prevalence of Autism in Australia. Report commissioned by the Advisory
Board on Autism Spectrum Disorders.
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