People on the autism spectrum vary enormously from each other but they all have restricted, repetitive patterns of behaviour, interests, or activities of one kind or another.
For example, they may
- have an overwhelming interest in something, such as transport systems or Dr. Who
- stick to specific routines or rituals, such as always going to the shops the same way
- repeat the same movements, such as flapping their hands over and over again
- be hypersensitive to certain sounds, such as telephones
It is worth noting that some people on the autism spectrum like their repetitive behaviours and consider them useful ways to deal with stressful events.