Autism is one of many diagnoses that fall under the umbrella of Pervasive Developmental Disorders (PDD). Signs of the disorder normally develop before the age of three. It appears to be more common in boys than girls with little ethnic, social or racial boundaries (Autism Depot). Symptoms of autism fall under three categories: limitations in social interaction, limitations in communication and repetitive patterns of behavior, interest and activities (Hamilton 41). Approximately 25% to 40% of autistic children develop epilepsy by adolescence. Although there are no pharmacological treatments available for autism there is medication to help control the seizures caused by epilepsy. Approximately 75% of autistic children score below the normal range on intelligence tests, including Weschler Scales of Intelligence (WISC). Although their cognitive abilities show uneven levels of development, they commonly do better on spatially related tests, such as block design (Gray 11). Symptoms range from mild to severe in a wide variety of combinations. In fact, two children with autism can show very different symptoms from one another. The symptoms are also at times mistaken for shyness, hearing problems, hyperactivity and/or moodiness (Small). Unfortunately many children exhibit a number of these traits, which would explain why the signs of autism could be overlooked.
The estimated numbers of children that have autism vary. However, it is agreed amongst many professionals that between two and six in one thousand individuals have the disorder. Approximately three hundred sixty thousand (360,000) cases in the United States alone, making it one of the most common developmental disorders. In recent studies the numbers show an annual increase of 26%. Dr. Rimland, an expert in the study of autism, believes that these increases are due to increased use of antibiotics, reactions to childhood inoculations and pollutants in the environment.