*What we call autism is a set of 5 conditions which share symptoms. [which all fall under the umbrella as represented in the figure above.]
-Autistic Disorder
-Aspergers Disorder
-Retts Disorder
-Childhook Disintegrative Disorder (CDD)
-Pervasive Developmental Disorder or Not Otherwise Specified (PDD:NOS)Autism is a physical disorder of the brain that causes a lifelong developmental disability.

Autism usually manifests itself by the appearance of typical behavioral symptoms in the following areas:

*SIX MAJOR SYMPTOMS OF AUTISM*

For a more detailed description of these symptoms, click here.
1. Failure to develop normal socialization

2. Disturbances in Speech, Language, and Communication

3. Abnormal Relationships to Objects and Events

4. Abnormal Responses to Sensory Stimulation

5. Developmental Differences and Delays

6. Begins during infancy or childhood

Rett's Syndrome has been diagnosed only in females.

Symptoms can begin as early as five months and include: 

*slow head growth

*loss of hand movement

Children who have CDD have significant loss in previously acquired skills. 

Children develop normally for the first two years (i.e., appropriate communication, social skills, play, and adaptive behavior), but then have a clinically significant loss of skills before age 10 in two of the following areas:

*language

*social skills

*toileting

*play

*motor skills.

In addition, they exhibit abnormal functioning in at least two areas:

*Social interaction

*Communication