Autism spectrum disorder (ASD) is a neurodevelopmental disorder. In people with ASD, information is processed differently by the brain. In short, people with ASD do not have the same “filter” as neurotypical people: they perceive a lot of details and are often more sensitive (or sometimes less sensitive) to sensory stimuli such as sound, smell and touch. In addition, it is more difficult for people with ASD to see the bigger picture and they can sometimes have difficulty with abstract concepts.
The differences can manifest themselves in reactions that are unexpected or difficult for neurotypical people to understand. It can also cause problems socially because communication with other people without ASD sometimes goes less smoothly.
It is a term that includes the former terms autism, Asperger’s syndrome, and a number of other variations. Nowadays we speak of a spectrum because there are many different expressions, and the former subtypes have proved untenable according to specialists.