ADHD and Autism: Why Does this Dual Diagnosis Happen?

Attention Deficit Hyperactivity Disorder, or ADHD, is becoming a more and more common comorbidity with Autism Spectrum Disorder. At one point it was thought that having one of these diagnoses would disqualify you for the other, but that manner of thinking has drastically shifted over the past decade as our understanding of developmental disorders has shifted. 

Developmental disorders were previously thought of as categories within themselves, which is how the assumption that ADHD and ASD couldn’t exist in one brain developed. The idea was that since these disorders can often present in traits that oppose each other, the mechanism within the brain that caused the disorders must also be drastically different, to an extent wherein two could not exist in the same brain. Now, however, we know that these disorders occur in many areas at once, affecting the development of the whole brain, and that these developmental differences can produce multiple disorders, as it can affect different areas of the brain. 

ADHD and ASD are both disorders that heavily involve sensory sensitivity and processing, executive functioning, and emotion regulation. Because of this, the two disorders present like a venn diagram, with things like social difficulties differentiating ASD and attention and hyperactivity differentiating ADHD, with the aforementioned traits serving as the overlap of the two. Additionally, traits that are common with both disorders, but are not diagnostic criteria, are also frequently found to overlap. This means that the comorbidity of ADHD and ASD is actually a lot more common than previously considered, since it only requires one or two additional diagnostic criteria to qualify for both disorders. 

The presentation of both ADHD and ASD is a complex one, since both present on a spectrum. This is made additionally complicated by the fact that some traits can actually counteract each other, masking one diagnosis or the other. For example, someone with comorbid hyperactive subtype ADHD is more likely to talk a lot, be more impulsive, and engage in social behaviors than someone with only ASD. This sometimes results in a lack of diagnosis of ASD until later in life, when the social difficulties could become more pronounced.

The diagnosis of ADHD and ASD can be a complex process and often requires a familiarity with multiple presentations of both diagnoses. If you would like more information on ADHD and ASD assessments, or you would like info on how to help your teen with a dual ADHD/ASD diagnosis, please reach out to Mindful Healing.