What is Autism?

customer-help-question-graphic-iconAutism is a neurological disorder that typically is diagnosed by the age of three. The symptoms of autism involve three major areas of development, and impact a child’s abilities to:

  • Engage in reciprocal social interactions with others
  • Communicate with others in developmentally typical ways; and
  • Participate in a range of activities and behaviors typical of the child’s age and stage of development

One of the hallmarks of autism is that the characteristics vary significantly among different children with autism. No two children with autism are the same. That’s because the impairments can range from relatively mild to more severe. Autism spectrum disorders are found in all cultures and across all socio-economic groups, with the ratio of boys to girls diagnosed with ASD being 4 to 1.

What is causing the increase in autism prevalence?

people-person-graphic-icon-1In the past 30 years, the prevalence rate of ASD has skyrocketed. Recent estimates indicate that autism spectrum disorders occur in 1 out of every 54 children born (CDC, 2020). Autism is not rare. The importance of effective intervention is critical on a personal, professional, and societal level.

The short answer is that no one knows for sure. Some epidemiologists point to a broader definition of autism and an increasing awareness among medical professionals as key contributing factors. Others consider the potential impact of environmental factors (e.g. toxins). As more research is funded and completed, this question may soon be answered.

What does it mean for a student to have Asperger Syndrome?

book-apple-teacher-education-graphic-iconAutism Spectrum Disorder (ASD) is a complex developmental disability defined in terms of impairments in socialization, communication, cognition, and sensation.

Asperger Syndrome (AS), also known as Asperger’s Syndrome, is a term that was used by professionals between 1994 and 2013. During that time, Asperger Syndrome was one of five developmental disorders on the autism spectrum. Some people with Asperger Syndrome choose to continue identifying themselves as persons with AS. As with all diagnostic changes, the everyday use of the terminology will phase out over time.

Based on the DSM-IV, the main differences between Asperger Syndrome and classic autism exist in the language and cognitive areas. Children with Asperger Syndrome do not have delayed language development, unlike children with other forms of autism. Also, children with Asperger Syndrome display average to above-average intelligence. Like autism, there is no known cause or “cure” for Asperger Syndrome.

Asperger Syndrome is a neurological disorder that affects a person’s ability to communicate and relate to others. It is a lifelong disorder that carries with it considerable and long-term challenges. Although the characteristics of Asperger Syndrome will vary somewhat from person to person, common effects of the disorder include:

  • Trouble understanding social cues and conversational language styles
  • An inflexible adherence to routine or ritual
  • Repetition of movements or words and phrases
  • Difficulties with fine-motor skills and sensory integration
  • A persistent preoccupation with objects or narrowly focused topics of interest

In 2013, the American Psychiatric Association released the Diagnostic Manual of Mental Disorders, 5th Edition (DSM-V). Since then, Asperger Syndrome is captured under the broad term Autism Spectrum Disorder (ASD).
To learn more about how to support students with Asperger Syndrome, check out OAR’s Life Journey through Autism: An Educator’s Guide to Asperger Syndrome.

What are the main differences between the DSM-IV and DSM-V?


In the American Psychiatric Association’s Diagnostic Manual of Mental Disorders, 4th Edition (DSM-IV), autism spectrum disorders were categorized by separate disorders, including:

Autistic disorder (classic autism)
Asperger Syndrome / Asperger’s Syndrome (AS)
Childhood Disintegrative Disorder (CDD)
Rett Disorder / Rett Syndrome
Pervasive Developmental Disorder not otherwise specified (PDD-NOS)

Symptoms were organized into three core domains:

Communication deficits
Social interaction impairments
Restricted interests and repetitive behaviors


In 2013, the APA combined the four disorders under the broad term Autism Spectrum Disorder (ASD). Under the DSM-V, people diagnosed with ASD are now evaluated based on their symptoms and the severity in which they exhibit them under two domains:

Deficits in social communication and social interaction
Restricted repetitive behaviors, interests, and activities (RRB)

Symptoms in both domains must be present in order for people to receive the ASD diagnosis. For those who have difficulty communicating or interacting socially but do not exhibit RRBs are diagnosed with social communication disorder, not ASD.

Individuals with ASD vary significantly from one another. Their ability to function independently can be further clarified with a diagnosis of Autism Spectrum Disorder – Level 1, Level 2, or Level 3:

Level 1 – Requiring support
Level 2 – Requiring substantial support
Level 3 – Requiring very substantial support

Overall, the changes from DSM-IV to DSM-V are aimed to better inform clinicians to consistently and more accurately diagnose their patients. In theory, the specified levels of severity allow practitioners to have some sense of the amount of supports needed.

What is PDD-NOS?

exclamation-mark-urgent-notification-important-deadline-graphic-iconPervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS) was the term used in the DSM-III and DSM-IV to identify a condition that shares the same central features as autism, yet did not meet all the criteria for an actual diagnosis of autism or Asperger Syndrome. While learners with a PDD-NOS diagnosis were presented as being “less affected” than learners with autism, the course of intervention generally paralleled that of someone with an autism diagnosis.

Since the release of the DSM-V, PDD-NOS is now captured under the broad term Autism Spectrum Disorder (ASD).