How Does the Autistic Brain Work?

The Facts

Autism is one of five pervasive developmental disorders of the brain causing problems in the areas of social interaction, communication, behavior and oftentimes moderate mental retardation. Autism appears in one of every 150 births and has a growth rate of 10 to 17 percent each year.
Individuals with autism are said to process incoming information differently than others, focusing primarily on the details of an interaction or environment. Studies show a series of abnormalities taking place in the autistic brain.
Autism can occur within a broad functional spectrum, with low functioning abilities on one side and high functioning autistic abilities on the other. Individuals within the higher functioning range have average to above-average intelligence and can function within a normal lifestyle. This article will address findings related to how the autistic brain works.

Features

Research studies are still undecided as to what actually causes autistic brain dysfunctions, but clues have surfaced. Brain scans show differences in size and development of the parietal, occipital and temporal lobes. Size differences do vary according to the age of the individual, with children showing larger sized areas.
Neurotransmitter activity within the brain may be responsible for the chemical abnormalities, as autistic symptoms show improvement when medications targeting serotonin, norepinephrine and dopamine are administered. Studies also show problems occurring at the point where neurotransmissions are made, causing neuron-to-neuron processes within the brain to misfire. This would account for the high incidence of seizure disorders amongst autistic individuals.

History of

As of the early 1900s, autism was considered to be a form of schizophrenia. The word autism is derived from the Greek word "autos," or self. The Swiss doctors of the time identified autism's key characteristic to be "the isolated self."
By the 1940s, autism was viewed as a childhood condition in which social and emotional problems were exhibited, but doctors still associated it with schizophrenia. It was at this time that specific withdrawal behaviors were identified and assigned their own diagnosis. Doctors Leo Kanner and Hans Asperger are credited for what is currently known as Asperger's syndrome.

Treatment approaches for autism included electric shock, behavior modification, and medication. Further identification of pronounced emotional and behavioral dysfunction led doctors away from autism's association with schizophrenia. By the 1980's, treatment focused more intently on behavior therapy within controlled learning environments.

Types

So far, 4 types of autism have been identified within the population:
*Asperger's syndrome--typical autistic symptoms are not as pronounced in Asperger's, but individuals with this syndrome are more prone to depression and anxiety symptoms. Asperger's typically develops in boys after the age of 3.
*Rett Disorder--symptoms develop as early as 6-18 months old and only occur with girls. This is a progressive disorder that gets worse with age. Pronounced motor skill problems, inability to express emotions and a smaller brain weight and size are observed.
*Childhood Disintegrative Disorder--this is the most severe of the four. Individuals have minimal motor-skill abilities, poor language/interaction skills and a high incidence of seizure activity. Long-term care is required for individuals with childhood disintegrative disorder.
*Pervasive Developmental Disorder--includes autistic-like conditions that don't fit within the other classifications. Onset can occur between 2 and 12 years old. Development of social and communication skills is delayed. Individuals exhibit unusual repetitive behaviors, require a stable, unchanging environment and are prone to self-injury through biting, scratching or cutting.

Resources

• Autistic Society of America
• Autism Resources