By Benison Anne O’Reilly, co-author of The Complete (formerly Australian) Autism Handbook
Why is the autism spectrum so broad? Picture this: the university-educated woman speaking articulately in the media about the challenges of her condition. The severely disabled young man who’s never said a word who lashes out at his carers and requires around-the-clock care. These people couldn’t appear more different, yet they share the same diagnosis – they’re both on the autism spectrum. How can this be so? What we need to do is look past their obvious differences and see what these two share in common. To do this, we need to take a closer look at the official diagnostic criteria for autism spectrum disorder (ASD).
The best-known diagnostic criteria are those in the Diagnostic and Statistical Manual of Mental Disorders (DSM), published by the American Psychiatric Association, although similar criteria appear in the World Health Organisation’s International Classification of Diseases (ICD).
The fifth, most recent version of the DSM was published in 2013. The DSM-5 combined three previously distinct diagnoses — autistic disorder, Asperger’s disorder and pervasive developmental disorder not otherwise specified (
So now, when a person is diagnosed with autism, the professionals making that diagnosis don’t have to decide which of 3 boxes that person falls into, they simply designate ASD with a level of severity from 1 to 3, depending on how much support that person is likely to need (generally considered a proxy for severity).
In 2013, these changes were considered controversial but five years down the track there is growing acceptance that the DSM-5 criteria are probably an improvement on earlier versions.
So, what do all people with ASD have in common under DSM-5?
Essentially, people diagnosed with ASD must present with two overarching behaviours:
- Persistent deficits in social communication and social interaction.
- Restricted, repetitive patterns of behaviour, interests, or activities.
The DSM-5 goes on to describe the many ways these behaviours might present, ranging, for example, from ‘difficulties making friends’ to ‘a complete absence in interest’ in other people. From obsessive interests to persistent, intrusive motor movements such as flapping or finger-waving. In this way, it accounts for all levels of symptom severity.
One important thing to note is that it’s not enough to have a few autistic traits to qualify. For a person to receive an ASD diagnosis these behaviours must be negatively impacting on their life — the D in ASD. People with ASD, by definition, require more help and support in order to achieve the same quality of life as neurotypical individuals.
If that’s what they have common why then can two people with ASD appear so different?
Simply put, ASD is a largely genetic disorder that affects ‘brain wiring.’ The genetics are
highly complex and different mutations appear to result in different brain changes, symptoms and severity. There’s still a lot we don’t know.
Another important factor is co-diagnoses, which the DSM-5 specifically takes into
consideration. For example, someone with ASD and an intellectual disability will have more challenges to overcome than someone with ASD and a normal IQ. A person with ASD and
ADHD will probably be impulsive and have trouble paying attention in school, whereas someone with ASD and severe anxiety will tend to be shy and socially withdrawn. Language disability also commonly occurs alongside ASD, affecting speech development in those affected.
Finally, gender differences are increasingly being recognised. Girls with ASD seem better
able to compensate for their social difficulties (called ‘masking’) and have less obvious restricted interests. Many fall under the radar and are not diagnosed until adulthood, when they present with conditions such as anxiety, depression, eating disorders and self-harm.
When we take all these factors into consideration, it’s easy to come to the same conclusion as autistic academic, Dr Stephen Shore, when he said:
“If you’ve met one person with autism you’ve met one person with autism.”
Start Your FREE Trial Today!
The Parent Edition is available for download from the Australian and New Zealand Apple App Stores now.