Autism is a brain-based condition – that is, where the brain hasn’t developed in a typical way.
Although no two autistic children are the same, they all have:
- trouble interacting and communicating with others – for example, they might not use eye contact to get someone’s attention, or they can be confused by language and take things literally
- narrow interests – for example, they might collect only sticks or play only with cars
- repetitive behaviour – for example, they might make repetitive noises like grunts, throat-clearing or squealing, or do things like flicking a light switch repeatedly.
Also, autistic children are often under-sensitive or over-sensitive to taste, touch, sight and sounds. For example, they might be easily upset by certain sounds, or will eat only foods with a certain texture, or they might seek vibrating objects like the washing machine or flutter fingers to the side of their eyes to watch the light flicker.
raisingchildren.net.au uses ‘identity first’ language to talk about autism, rather than ‘person first’ language. This involves referring to ‘autistic children’, for example, rather than to ‘children with autism’. Many autistic people prefer this approach. We’re making this change over time, so you’ll still see some articles that use a different approach.
What causes autism?
We don’t know exactly what causes autism.
In autistic children, there might be early brain overgrowth. This means that the brain grows faster than average so that different parts of the brain don’t communicate with each other in a typical way.
Evidence also strongly suggests a genetic basis to autism. But it’s unlikely that one specific gene is responsible for autism. It’s more likely that several genes combine and act together. Researchers have found many possible genes that might play a role in the development of autism.
There’s no one answer to the question of what causes autism. But it’s clear that what parents do or don’t do doesn’t cause autism in children.
It’s common to see early signs of autism in a child’s first two years. And in these years, it’s especially important to watch children’s social communication development.
For example, in the first year of life, parents of babies later diagnosed with autism notice their child’s lack of interest in other people. Many of these babies don’t make eye contact with their parents while being held or during nappy changes. The lack of other behaviour like smiling and gestures is also a sign that a child isn’t developing in a typical way.
In the first two years, other signs might be a child not responding to their name, or focusing narrowly on activities like lining up toys.
Signs of autism become more noticeable in the toddler years, as children are expected to start talking and playing with other children. Autistic children might not be interested in playing with other children, or might speak in an unusual way – for example, in a monotone.
Signs of autism in older children and teenagers might become noticeable when children have difficulty adjusting to new social situations in the school environment – for example, staying on task, understanding and following instructions, making friends, and having age-appropriate interests.
Autism can be diagnosed from two years of age.
Diagnosis usually involves many specialists and professionals testing and assessing a child – this is called a multidisciplinary assessment.
There’s no single test for autism. Instead, diagnosis is based on:
- watching how children play and interact with others – that is, how children are developing now
- interviewing parents
- reviewing children’s developmental history – that is, how children have developed in the past.
Children will get a diagnosis of ‘autism spectrum disorder’ and a description of how severe their symptoms are and the amount of support they need. This ranges from ‘needing support’ to ‘needing very substantial support’.
Health professionals will also assess children’s language and cognitive abilities.
Children who show difficulties only in social communication might be diagnosed with social communication disorder, rather than autism spectrum disorder.
Concerned about your child’s development: what to do
If you’re concerned about your child’s development, talk to your child and family health nurse or GP about a developmental assessment. Getting an assessment and diagnosis is the first step to helping your child and getting services and programs suited to your child’s needs.
It’s important to get help and support as soon as possible. The sooner children get early intervention services, the more effective these services can be.
– Jenny, mother of Alexander, aged five
Different types of autism
In May 2013, the criteria that health professionals use to diagnose autism changed. This was when the 5th edition of the Diagnostic and statistical manual of mental disorders, or DSM-5, was published.
Before 2013, professionals diagnosed different types of autism – autistic disorder, Asperger’s disorder (also called Asperger’s syndrome), and pervasive developmental disorder – not otherwise specified (PDD–NOS).
Under the DSM-5, there’s just one diagnosis – autism spectrum disorder.