Why is Autism called Autism Spectrum Disorder?

Autism Spectrum Disorder (ASD) is defined as a neurodevelopmental disability causing difficulty with social communication and interaction with other people, as well as, restricted interests and repetitive behaviors (American Psychiatric Association, 2013).  For ASD, there is also a level of severity that should be specified that ranges from Level 1 to Level 3.  The severity levels focus on the level of impairment and also the level of support needed to be successful in day-to-day activities.   Often, there is an assumption that the route from Level 1 to 3 is linear and many people refer to people with ASD as “high-functioning” for Level 1 or “low-functioning” for Level 3, implying that there are two ends of a linear continuum, but ASD is far more complex than that.  An example of this is the assumption that because someone is nonverbal, they are “low-functioning”.  When in fact, there are many people who are nonverbal, but have average and above-average intelligence and are highly skilled and less affected in many areas of functioning.

Previous versions of the DSM included multiple diagnoses that are now all included in the ASD diagnosis.  There were separate diagnoses for Asperger’s Disorder, Autistic Disorder, and Pervasive Developmental Disorder.  There were three criteria that had to be met for a diagnosis of Autistic Disorder: social impairments, communication impairments, and restricted, repetitive, stereotyped behavior.  Asperger’s Syndrome had the same criteria except it did not include communication impairments.  Many associate people with a diagnosis of Asperger’s as “high-functioning” and those who had a diagnosis of Autistic Disorder as “low-functioning”, with language ability being the hallmark trait making this distinction.  When the update to the DSM 5 occurred, it combined all of the diagnoses into ASD and combined the social and communication impairments into one criterion.  According to the American Psychiatric Association, “This spectrum will allow clinicians to account for the variations in symptoms and behaviors from person to person.”

While the DSM5 lists two criteria of social communication/interaction and repetitive, stereotyped behaviors and interests, they can present in extremely different ways in individuals.   I have often heard people say, “He has good eye contact, so he can’t have Autism”.  This is inaccurate, while many people with ASD have limited eye contact, it is not true of every person with ASD.   The complexity of the presentation of ASD is better conceptualized by the new name for the diagnosis and inclusion of the word “Spectrum”.  It is a much more representative label and speaks to the much less binary nature of the symptoms of ASD.  There are individual variations in the type and severity of the symptoms each person has.  There is a saying in the autism community that “If you have met one person with Autism, you have met one person with Autism”.  This speaks to the spectrum aspect of ASD.  The way that the different strengths and challenges present is very different for every person.  For example, two individuals who would be considered “low-functioning” do not necessarily have symptoms that present in the same way.

The degree to which a person is affected is individualized across all of these different areas.  One individual may have significant motor impairments, have typical verbal language, have limited nonverbal communication, have severe aggressive behaviors, and flap their hands.  Another person may have no motor impairments, limited verbal and nonverbal communication, have no aggressive behaviors, and have an intense interest in Disney.  Their level of functioning and/or impairment in each area is not consistent across all areas.  Having severe aggressive behaviors does not mean that the individual will have severely impacted verbal abilities, sensory sensitivities, or motor functions.  Having a really high verbal ability does not mean they are less impacted in other areas.  It is a unique mix of abilities and needs for each person.  The graphic below represents a number of areas that can be affected by ASD.

There is also complexity in the potential symptoms listed for ASD versus the various ways the symptoms can present.  The list of symptoms in the diagnostic criteria is not an exhaustive list and the clinician needs to be familiar with symptomology beyond just what is listed.  They also need to be familiar with developmentally expected behavior so that they can compare what is observed and reported to typical development.  For example, if parents report that the child is reactive to loud noises, that doesn’t necessarily mean they have sensory sensitivity.  It could be a developmentally appropriate reaction to hearing a loud noise, but it is likely a sensory sensitivity if the individual is 15 years old and has a tantrum for 20 minutes every time they hear a loud noise.

I appreciate the aspect of autism as a spectrum disorder that allows for more individuality in the diagnosis.  It has broadened the perspective of what ASD is and how it is perceived.  Now if someone has ASD, it is not assumed they are nonverbal with a co-occurring Intellectual Developmental Disability.  ASD now can allow people to be seen for their unique qualities.  I feel that it also encourages more focus on the strengths of the individual and not just areas of concern.  By seeing the whole person and their strengths and weaknesses across all areas, it helps to provide better treatment for each person.

 

References:
American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders(5th ed.). Arlington, VA: Author.