Autism is a neurological disorder. According to the autism advocacy organisation Autism Speaks, "Autism is a general term used to describe a group of complex developmental brain disorders known as Pervasive Developmental Disorders." In recent years, it has become highly prevalent, with 1 in 110 children diagnosed with the disorder. Though there are no medical tests to diagnose autism, there are behaviours and symptoms of autism that can indicate the disorder.
Impaired Social Development
One of the classic signs of autism in children is impaired social development. Children with autism tend to prefer playing by themselves, often do not respond to their names when they are called and do not respond to social stimuli. Often, these children do not know how to interact with others, understand how to respond to what others say and do, or know how to relate or display emotions. They tend to make attachments with inanimate objects rather than with other people.
Making eye contact is a normal social interaction between people. This action shows that you are paying attention to and understanding the person with whom you are speaking. Autistic children often make little or no eye contact when they are speaking or when they are spoken to. Though the reason for this is not completely understood, it is suspected that it is related to an inability to properly interact.
Repetitive or Self Stimulatory Behaviors
People with autism commonly engage in repetitive or self stimulatory behaviours. Such behaviours may be obvious and may include things such as arm flapping, snapping fingers, making repetitive sounds and jumping up and down. Some behaviours may be more difficult to notice, such as eye rolling, hair twirling and finger or toe tapping. It is not known why people with autism engage in these behaviours, however, it has been noted that some people display such actions when they are nervous or agitated and others do it without any noticeable stimuli.
Autistic children often have difficulty with sensory processing. Sights and sounds that would not bother a typically developing person can be extremely irritating to some autistic people. These individuals are hypersensitive and things such as flashing lights, fire alarms, loud music and even a light touch can cause pain or discomfort. There are also those that fall on the other end of sensory processing in that they do not respond to things that would be considered painful to a normally developing person. These children do not express discomfort if they are sick or if they injure themselves.