Autism

Autism is a brain development disorder that shows symptoms before a child is three years old and has a steady course with no remission. Its characteristic signs are impairments in social interaction and communication, as well as restricted and repetitive behavior. These characteristics distinguish autism from milder pervasive developmental disorders (PDD) or autism spectrum disorders (ASD), and reflect Leo Kanner's first descriptions of autism, which emphasized "autistic aloneness" and "insistence on sameness".

Heritability contributes about 90% of the risk of a child developing autism, but the genetics of autism are complex and typically it is unclear which genes are responsible. In rare cases, autism is strongly associated with agents that cause birth defects. Many other causes have been proposed, such as exposure of children to vaccines; these proposals are controversial and the vaccine hypotheses have no convincing scientific evidence.

Autism affects many parts of the brain, but how this occurs is poorly understood. Parents usually notice warning signs in the first year or two of their child's life. Rapid evaluation by a specialist is important as, although there is no cure, early intervention may aid attempts to help children gain self-care and social skills. However, only a very few of these interventions are supported by scientific studies. With severe autism independent living is unlikely, but with milder autism there are some success stories as adults, and an autistic culture has developed, with some seeking a cure and others believing that autism is simply another way of being.

Most recent reviews estimate a prevalence of 1–2 per 1,000 people for autism and close to 6 per 1,000 for ASD, with ASD averaging a 4.3:1 male-to-female ratio. The number of people known to have autism has increased dramatically since the 1980s. Some of this increase is undoubtedly due to changes in diagnostic practice; it is not known whether prevalence has increased as well.

Neuropsychology
Two major categories of cognitive theories have been proposed about the links between autistic brains and behavior.
The first category focuses on deficits in social cognition. Hyper-systemizing hypothesizes that autistic individuals can systematize—that is, they can develop internal rules of operation to handle internal events—but are less effective at empathizing by handling events generated by other agents. It extends the extreme male brain theory, which hypothesizes that autism is an extreme case of the male brain, defined psychometrically as individuals in whom systemizing is better than empathizing. This in turn is related to the earlier theory of mind, which hypothesizes that autistic behavior arises from an inability to ascribe mental states to oneself and others. The theory of mind is supported by autistic children's atypical responses to the Sally-Anne test for reasoning about others' motivations, and is mapped well from the mirror neuron system theory of autism.
The second category focuses on nonsocial or general processing. Executive dysfunction hypothesizes that autistic behavior results in part from deficits in flexible planning, working memory, and impulse control. One strength of the theory is predicting stereotyped behavior and narrow interests. Weak central coherence theory hypothesizes that a limited ability to see the big picture underlies the central disturbance in autism. One strength of this theory is predicting special talents and peaks in performance in autistic people. A related theory enhanced perceptual functioning focuses more on the superiority of low-level perceptual operations in autistic individuals. The latter two theories map well from the underconnectivity theory of autism.
Neither category is satisfactory on its own. Social cognition theories poorly address autism's rigid and repetitive behaviors, while the nonsocial theories have difficulty explaining social impairment and communication difficulties.

What causes autism?
Autisms is a complex pervasive developmental disorder that involves the functioning of the brain. It is a neurological disorder and not simply a psychiatric disorder, even though typical characteristics include problems with social relationships and emotional communication, as well as stereotyped patterns of interests, activities and behaviors. It also involves problems with sensory integration. Typically, it appears during the first three years of life. It is estimated that it occurs in approximately 2 to 6 in 1,000 individuals, and is 4 times more prevalent in males than females.
It is most prevalent in Caucasian males.

Symptoms of Autism
The main autism symptoms involve language, social behavior, and behaviors concerning objects and routines:

• Communication both verbal (spoken) and non-verbal (unspoken, such as pointing, eye contact, or smiling)
• Social interactions—such as sharing emotions understanding how others think and feel (sometimes called empathy), and holding a conversation, as well as the amount of time a
person spends interacting with others
• Routines or repetitive behaviors often called stereotyped behaviors, such as repeating words or actions, obsessively following routines or schedules, playing with toys or
objects in repetitive and sometimes inappropriate ways, or having very specific and
inflexible ways of arranging items

People with autism might have problems talking with you, or they might not look you in the eye when you talk to them. They may have to line up their pencils before they can pay attention, or they may say the same sentence again and again to calm themselves down.

They may flap their arms to tell you they are happy, or they might hurt themselves to tell you they are not. Some people with autism never learn how to talk. These behaviors not only make life challenging for people who have autism, but also take a toll on their families, their health care providers, their teachers, and anyone who comes in contact with them.

Treatment Options for Autism
As of 2004, autism is treatable, but not curable (although there is an organization called "Cure Autism Now"). Early diagnosis and intervention are vital to the future development of the child. It is widely considered that a cure will be impossible to develop for quite some time, because autisms involves aspects of brain structure that are determined very early in development. Thankfully, there are a variety of medications designed to help minimize the symptoms of autism, as well as help enhance learning. In some cases, these medications can help people with autism lead a nearly 'normal' lifestyle.