Autism and Aspergers - 04-10-2007, 08:07 AM
(taken from Wikipedia)
Autism is classified by the World Health Organization (WHO) and American Psychological Association as a developmental disability that results from a disorder of the human central nervous system. It is diagnosed using specific criteria for impairments to social interaction, communication, interests, imagination and activities. The causes, symptoms, etiology, treatment, and other issues are controversial.
Autism manifests itself "before the age of three years" according to the WHO's International Classification of Diseases (ICD-10) Children with autism are marked by delays in their "social interaction, language as used in social communication, or symbolic or imaginative play" (Diagnostic and Statistical Manual of Mental Disorders).
Autism, and the other four pervasive developmental disorders (PDD), are all considered to be neurodevelopmental disorders. They are diagnosed on the basis of a triad, or group of three behavioral impairments or dysfunctions: 1. impaired social interaction, 2. impaired communication and 3. restricted and repetitive interests and activities. These three basic characteristics reflect Dr. Leo Kanner's first reports of autism emphasizing "autistic aloneness" and "insistence on sameness."
From a physiological standpoint, autism is often less than obvious in that outward appearance may not indicate a disorder. Diagnosis typically comes from a complete patient history and physical and neurological evaluation.
The incidence of diagnosed autism has increased since the 1990s. Reasons offered for this phenomenon include better diagnosis, wider public awareness of the condition, regional variations in diagnostic criteria, or simply an increase in the occurrence of ASD (autism spectrum disorders). The United States Centers for Disease Control (CDC) estimate the prevalence of autism spectrum disorders to be about one in every 150 children. In 2005, the National Institute of Mental Health (NIMH) stated the "best conservative estimate" as 1 in 1000. In 2006, NIMH estimated that the incidence was 2-6 in every 1000.
There are numerous theories as to the specific causes of autism, but they have yet to be fully supported by evidence (see section on "Causes" below). Proposed factors include genetic influence, anatomical variations (e.g. head circumference), abnormal blood vessel function and oxidative stress. Their significance as well as implications for treatment remain speculative.
Conversely, some autistic children and adults are opposed to attempts to cure autism. These people see autism as part of who they are, and in some cases they perceive treatments and attempts of a cure to be unethical.
On the surface, individuals who have autism are physically indistinguishable from those without. Some studies show that autistic children tend to have larger head circumferences but the significance in the disorder is unclear. Sometimes autism co-occurs with other disorders, and in those cases outward differences may be apparent.
Individuals diagnosed with autism can vary greatly in skills and behaviors, and their response to sensory input shows marked differences in a number of ways from that of other people. Certain stimulations, such as sounds, lights, and touch, will often affect someone with autism differently than someone without, and the degree to which the sensory system is affected can vary greatly from one individual to another.
Autistic children may display unusual behaviors or fail to display expected behaviors. Normal behaviors may develop at the appropriate age and then disappear or, conversely, are delayed and develop quite some time after normal occurrence.In assessing developmental delays, different physicians may not always arrive at the same conclusions. Much of this difference between diagnosis is due to the disputed criteria for autism.
Deciding how a child should behave is also difficult because diagnostic tests have to be objective, which is not a simple thing to accomplish.Because of this practitioners and researchers in pediatrics, child psychology, behavior analysis, and child development are always looking for early indicators of autism.
The diagnosis of autism must meet specific criterion but there are also many characteristics that are idiosyncratic. Thus, Autism is not a "one size fits all" label. In other words the spectrum disorder encompasses a very wide range of behaviors and symptoms.
Some behaviors cited by the National Institute of Child Health and Human Development (listed below) may simply mean a normal delay in one or more areas of development, while others are more typical of ASDs—Autistic Spectrum Disorders.
The list below is not all-inclusive, and generally applies to children and not adults. Furthermore, while some of these behaviors might be seen in a person with autism, others may be absent.
Noted Behaviors in Children