Autism or Autism Spectrum Disorder (ASD) is a group of developmental disorders of the nervous system, whose main manifestations include defects in social interactions, communication, and repetitive behaviors and limited interests. At one end of the autism spectrum, there is an IQ below 40 and at the other end there are very genius people with high intelligence abilities (Newton, Einstein, Tesla, etc.), although they have defects in social and communication interactions.

The main manifestation of social deficits in autism includes poor eye contact, lack of emotions or social confrontation, deficits in using non-verbal behaviors and age-appropriate communication.

In addition to deficits in social skills and stereotyped and repetitive behaviors, autistic children have delays in motor skills. Delays in movement abilities in autistic children are diverse and include delays in sitting, crawling, walking, and abnormal stepping, poor postural control, and inability to plan movements.

Autism is considered a spectrum because its manifestations are very diverse and heterogeneous. For example, cognitive and verbal disabilities are very severe in some of these patients, while others have mental genius and very high talent, in other words, autistic children are so-called non-verbal.