What is Autism?

Autism spectrum disorder (ASD) is a neurodevelopmental disability, which means that it affects the functioning of the brain. Signs of autism typically appear during the first three years of life.[1] Autism affects a person’s ability to communicate and interact with others. ASD is defined by a certain set of behaviors and is a “spectrum condition” that affects individuals differently and to varying degrees.[2]

Here are just a few of the behavioral characteristics associated with ASD:[1]

  • Prefers to be alone
  • Has a lack or impairment of conversational skills
  • Does not develop age-appropriate peer relationships
  • Has an aloof manner
  • Exhibits little or no eye contact
  • Is detached from feelings of others
  • Has an inappropriate attachment to objects
  • Repeats words or phrases (echolalia)
  • Speaks on very narrowly focused topics
  • Has difficulty talking about abstract concepts
  • Peculiar voice characteristics (flat monotone or high pitch)
  • Does not like change in routine or environment
  • Will eat only certain foods
  • Does not like to be touched
  • Repetitive motor movements (rocking, hand-flapping)
  • Low muscle tone
  • Uneven fine and gross motor skills
  • Covers ears
  • Does not react to pain
  • Becomes hyperactive or totally nonresponsive in noisy or bright environments
  • Eats or chews on unusual things
  • Hits or bites self and/or others
  • Has temper tantrums for no apparent reason and is difficult to calm down
  • Lacks common sense
  • Does not appear to understand simple requests
  • Frequent diarrhea, upset stomach, or constipation.


There is no known single cause for autism spectrum disorder, but it is generally accepted that it is caused by abnormalities in brain structure or function. Researchers are also investigating a number of other theories, including the links among heredity, genetics, and medical problems.[3]

In many families, there appears to be a pattern of autism or related disabilities, which supports the theory that the disorder has a genetic basis. It also appears that some children are born with a susceptibility to autism, but it has yet to be determined if there is a single “trigger” that causes autism to develop. Some such triggers could potentially come from issues during pregnancy or from environmental factors such as viral infections, metabolic imbalances, or chemical exposure.[3]

Comorbidity & Related Conditions

The term “comorbidity” means that there is a presence of one or more conditions that often go along with a person’s main diagnosis. For example, someone with autism may very likely also have ADHD, OCD, anxiety, or a depressive disorder. Keep in mind: this does not mean that any of these comorbid conditions is their primary diagnosis; they are merely additional diagnoses that appear in someone with autism. Many people do not understand this and believe that an issue such as ADHD is the main issue, which leads to many misdiagnoses.[1]

Many people with autism also suffer from related medical conditions that include but are not limited to:[4]

  • Seizures: It is estimated that around 30% of people with autism develop epilepsy.
  • Sensory Processing Disorder (SPD): Many people with autism have SPD, which involves unusual sensitivities to sounds, sights, touch, taste, and smells.
  • Sleep Problems:  Many individuals with autism have sleep problems. Night waking may be due to gastrointestinal issues, allergies, environmental intolerances, seizures, sleep apnea, sleep terrors, or confusional arousals.
  • Chronic Constipation and/or Diarrhea:  Medical literature states that about 47% of adults on the spectrum and 45% of children with autism have gastrointestinal symptoms.

What is Asperger Syndrome?

Asperger syndrome (also known as Asperger’s or AS) was coined in the 1940s by Hans Asperger, and he used it to describe individuals who have “autism-like behaviors and difficulties with social and communication.” Since then, many believe that AS is simply a milder form of autism and use the term “high-functioning autism” instead.[1]

However, Asperger syndrome is no longer a formal diagnosis. Along with the publication of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013, the four pervasive developmental disorders (autistic disorder, Asperger syndrome, childhood disintegrative disorder, and pervasive developmental disorder not otherwise specified) were placed under one umbrella diagnosis: autism spectrum disorder (ASD). Therefore, those who would have gotten diagnosed with Asperger’s in the past are now simply diagnosed with autism spectrum disorder or, more specifically, high-functioning autism.[1]

One major difference that has been used to differentiate between Asperger syndrome and classic autism is that there is no speech delay in Asperger’s. Often times, people with AS excel in their language abilities, but they may struggle to grasp the subtleties of language, such as misunderstanding irony and humor or taking idioms literally.[1]

Another distinction between Asperger’s and classic autism concerns their cognitive abilities. While some people on the spectrum have intellectual disabilities, a person with Asperger’s cannot have a cognitive delay, and most possess average to above-average intelligence.[1]

Image courtesy of Harkla.co


  1. Sicile-Kira, C. (2014). What is autism spectrum disorder and how to know if a person has ASD. Autism spectrum disorder: the complete guide to understanding autism (revised ed.) (18-34). New York, NY: Perigree, 2014.
  2. Autism Society (2016). What is autism? Retrieved from http://www.autism-society.org/what-is/.
  3. Autism Society (2016). Causes. Retrieved from http://www.autism-society.org/what-is/causes/.
  4. Autism Society (2016). Related conditions. Retrieved from http://www.autism-society.org/what-is/diagnosis/related-conditions/.
  5. Autism Society (2016). Asperger’s Syndrome. Retrieved from http://www.autism-society.org/what-is/aspergers-syndrome/.