Differences Between ADHD and ASD

Differences Between ADHD and ASD

Erin Yilmaz
4 minute read

differences between ADHD and ASD
Article originally published on Dr. Marshack's Blog, 01/20/2020.

Differences between ADHD and ASD

by Kathy J. Marshack, Ph.D.

Can a child have both ADHD and ASD? The short answer is yes and the sooner it’s diagnosed, the better. 

difference between ASD and ADHD

Dr. Amir Miodovnik, a developmental pediatrician at Boston Children’s Hospital authored a study, which shows that symptoms of ADHD may, in fact, conceal ASD in very young children. The study appeared in the October 2015 print issue of Pediatrics. 

Dr. Miodovnik concluded that ADHD symptoms sometimes masks “Autism” in very young children. A doctor may stop looking when he or she sees ADHD symptoms and then they miss that the child is also suffering from “Autism Spectrum Disorder”

The study found out that it took an average of three years longer to diagnose “Asperger Syndrome” in children with ADHD. This delay can have a big impact on the future of the child with many types of research showing that the earlier you implement therapies for autism, the better children do in terms of outcome. 

For this study, researchers looked at data on nearly 1,500 children with “autism” drawn from the 2011-2012 National Survey of Children’s Health. 

About 43% of these children have been reported to have both ASD and ADHD. More than two out of five children were diagnosed with ADHD first. About 81% of them were diagnosed with “autism” after age 6. Children already diagnosed with ADHD were nearly 17 times more likely to be diagnosed with “Asperger Syndrome” after age 6 compared to children who only received a diagnosis of “autism”. You can continue to read more about this study here.

What similar symptoms do “Asperger Syndrome” and ADHD have?

ASD and ADHD are different neurological disorders, however, they do have some symptoms in common.

  • Hyperactivity
  • Impulsivity
  • Inattentive
  • Social awkwardness
  • Difficulty in interactions with others

What are some differences between ADHD and ASD?

difference between autism and ADHD

”Asperger’s Syndrome”

  • All-absorbing interest in specialized topics, like sports statistics or dinosaurs
  • Lack of nonverbal communication – eye contact, facial expressions, body gestures
  • Lack of empathy or understanding others’ feelings
  • Monotone pitch or lack of rhythm when speaking
  • Missed motor skill development mile markers, such as catching a ball

Is it ASD or autism



  • Easily distracted and forgetful
  • Problems processing information accurately and quickly
  • Touching or playing with everything especially in a new environment
  • Very impatient and can’t wait their turn
  • Over-reacting when upset or bothered, without consideration for others

Similar symptoms make it harder and more complex to diagnose “Asperger Syndrome” in children with ADHD. Read these two blogs to understand a few of the challenges people with these disorders are facing: Male and Female Differences in “Autism Spectrum Disorder” and Do You Live in the ADHD or “ASD” Time Zone?

Dr. Miodovnik recommends that parents who believe that a child younger than five has ADHD should take their child to a developmental pediatrician, rather than a family physician, to make sure that possible autism will not be overlooked. He also recommends this, because managing a child with ADHD can be complicated.


If you have a loved one that has been diagnosed with “ASD”, you will also benefit from learning how science is unlocking the key to understanding “Asperger” behavior. My book, Out of Mind – Out of Sight: Parenting with a Partner with Asperger Syndrome (ASD), explores the science behind Asperger’s. If you want to understand your “Aspie” better, this is a must read.


Other suggested reading related to the above blog post:

Underlying Characteristics Checklist: Adult Self-Report (UCC-SR-ADULT)

Underlying Characteristics Checklist: Adolescent Self-Report (UCC-SR-ADOL)


Not Your Neurotypical Guy

Starting Points

About the Author

« Back to Blog