Autism is a neuropsychological disorder that affects about 9 children out of every 1,000 in the United States. Because of its relatively high prevalence and ability to impact a person’s entire life, understanding autistic behavior is crucial for many people in America today.
While autism’s underlying cause is not fully understood, it generally appears during early childhood, with the first symptoms occurring at around six months of age, and behaviors becoming very noticeable by the time a child is two or three years old. The main three symptoms that appear are difficulty in social interaction, difficulty communicating with others, and repetitive behaviors and a narrow range of interests.
The difficulty in social interaction leads to a different track of social development. Autistic behavior in this category would include social impairments and problems intuiting how another person would feeling, or what they would think in a given situation. In infancy, this can manifest by a low rate of response to one’s own name, a lack of interest in social situations, and decreased incidences of smiling.
Communication difficulties are another sign of autism. Infants may not babble as frequently or as early, they may vocalize in a manner inconsistent with understanding another person, and may not respond to vocal stimuli as often as children without autism. As the child gets older, he or she may be less likely to vocalize or form complete sentences, they do not share experiences or stories as often, and sometimes they may limit their vocalizations to repeating words they have just heard spoken, a phenomenon known as echolalia. Autistic children also do not match gestures with speech, and may have trouble determining what a person is pointing at.
Repetition of behavior is another standard symptom of autism. Repeated motions like rocking or hand waving is known as stereotypy. Compulsive behavior refers to those types of behaviors that the child seems to be forced to do, such as stacking or arranging objects in a particular way. Autistic children may also show a love of routines, for example, having to do the same activities at the same time each day, and disruption of this pattern may upset the child. In the same way, rearranging toys or furniture may cause the child to become upset. Restricted behavior is also present many times, where a child will only have an interest in a narrow range of activities, sometimes to the point of only being interested in a single television show or game. In some extreme cases, autistic people will even injure themselves in a compulsive fashion.
Although every person with autism is different, in most cases there is a combination of these behaviors, which give some commonalities to this spectrum disorder.

