Autism is a developmental disorder that begins early in childhood; it is usually noticed in children by age 3. Defining characteristics of autism include communication deficits, poorly developed reciprocal social interactions, stereotyped behaviors, and restricted interests. These deficits occur at different levels of severity which has evolved into the contemporary view of autism as a spectrum disorder, and it is often referred to as Autism Spectrum Disorder (ASD), Autistic Disorder (AD), or Autism.
Traditionally, the autism range has included Autistic Disorder, Asperger Syndrome, and Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS).Autistic Disorder is sometimes called classic autism. It is characterized by:Significant language delays including reduced instances of language that has communicative and reciprocal intent.
Minimal reciprocal social interactions autism. For example, avoidance of eye contact, lack of appropriate facial expressions, inability to appropriately communicate emotions, lack of understanding of shared emotions, and inability to use verbal and nonverbal behaviors for social interchange.
Stereotyped behaviors and restricted interests. These may include unusual sensory interests toward objects, unusual or repetitive hand and finger movements, and excessive interest or reference to either unusual or highly specific topics or objects.
Asperger Syndrome, while somewhat milder than Autistic Disorder, has both similar and distinct characteristics including:
Difficulty with the social aspects of speech and language such as limited range of intonation, one-sided conversations, literal interpretations, and inability to shift topics. Vocabulary development is usually advanced while understanding of figurative language is a weakness.
Difficulty with social cognition a lack of social and/or emotional reciprocity, eye contact, and friendships. Social awkwardness such as not reacting appropriately to social interactions and not recognizing other’s feelings or reactions. Difficulties with social cognition may result in behavioral rigidity.
Restricted and repetitive behaviors, interests, and activities. This may result in inflexibility in regard to routines. Preoccupation with a narrowed topic of interest which often dominates conversations and thoughts.
Pervasive Developmental Disorder-Not Otherwise Specified is used to categorize those individuals who meet some, but not all, of the criteria for Autistic Disorder or Asperger Syndrome. PDD-NOS is usually marked by fewer and milder symptoms than Autistic Disorder or Asperger Syndrome. Pervasive deficits in the development of reciprocal social interaction, communication, or stereotyped and restricted behaviors are apparent.