Diagnosis of autism
The diagnosis of ASD is based on :
- The presence of the 3 signs of the social interaction/communication dimension
- The presence of at least 2 signs of behaviour and interests
- The presence of signs since early childhood
- A significant impact on the person’s life
The signs must not be better explained by another neurodevelopmental or mental disorder.
We then specify the level of severity (3 different levels), and whether or not the ASD is associated with :
- Intellectual development disorder
- An impairment of language
- A known environmental or genetic factor
- Another neurodevelopmental or mental disorder
A l’Institut du Cerveau
The team co-directed by Mathias PESSIGLIONE, an Inserm researcher, in collaboration with a Canadian team, studied mimetic desire in autistic people, which could explain the alteration in their social interactions and motivation.
Mimetic desire corresponds to the spontaneous tendency to desire the same things as others, for example for children the same toy as their classmate.
People with ASD are often disorientated by changes in their environment, such as the arrangement of furniture at home or a change of teacher at school. They often exhibit repetitive behaviours such as rocking or clapping. Repetitive patterns can also be observed, such as eating the same food at every meal or watching the same video every day.
Children and adults with autism may have very specific, narrow and sometimes strange interests, such as electric motors, bin bags or traffic signs.
Symptoms related to the 5 senses may manifest as hyper- or hypo-reactivity to smell, cold or pain.
People with autism frequently have one or more associated disorders (mental disorders or other disorders, e.g. cardiac, neurological, etc.).
Around a third of people with autism have an intellectual development disorder (i.e. an IQ <70).
It is estimated that 1 in 5 people with autism suffers from epilepsy.
Some patients have extreme, highly focused and specialised abilities, such as a strong aptitude for mental arithmetic or an absolute ear. But these abilities are rare and do not form part of the diagnostic criteria.