ADHD and Autism: Similarities, Differences, and When They Interconnect

Similarities Between ADHD and Autism

ADHD and autism are both neurodevelopmental disorders, which means they can affect a variety of areas related to the central nervous system. This includes language, memory, movement, attention, and social skills.

Neither ADHD or autism can be diagnosed with a simple physical test, like bloodwork or a brain scan. Instead, clinicians have to rely primarily on the presence of certain symptoms. This is where the similarities between autism and ADHD can become more noticeable. Prior to a diagnosis, certain symptoms can be easily assigned to either one.

Some areas where ADHD and autism symptoms overlap in a significant way include:

Impulsivity
Learning challenges
Social challenges
Executive dysfunction
Emotional dysregulation
Fidgeting or stimming

A thorough assessment is required in order to get to the root cause of the symptoms and deliver an accurate diagnosis. For example, if an individual seems to be not listening to someone speaking to them, it could be an indicator of either ADHD or autism. Subtle hints can make the difference in these assessments, like whether the individual is inattentive due to ADHD or they’re not making eye contact during conversations due to autism.

Similarly, fixations can be an area which makes an accurate diagnosis more difficult. Many people assume that ADHD makes it hard to focus on anything for extended periods of time, but people with this condition actually tend to hyperfocus on certain topics or activities to the point where it’s hard to break their attention. Those with autism also experience this type of intense focus which can be beneficial in some contexts and detrimental in others. This is another example of the types of overlaps which can make it difficult to differentiate between ADHD and autism.

Differences Between ADHD and Autism

While there are many similarities between autism and ADHD, there are some key differences which stand out. The primary areas where an individual experiences challenges are often indicators of which disorder that person has.

With ADHD, the primary challenges tend to occur in the areas of inattention and/or hyperactivity-impulsivity. For autism, the primary challenges are associated with social communication deficits and restrictive, repetitive behaviors.

When overlaps in symptoms still make it difficult to differentiate whether someone has ADHD or autism, there are other indicators and diagnostic criteria which clinicians can use to narrow it down. For example, the age of onset is usually younger for autism than ADHD. Symptoms of ASD tend to become apparent around 12 to 18 months, while ADHD symptoms often start to emerge somewhere around the ages of 3 to 6 years.

When ADHD and Autism Overlap: AuDHD

With so many overlaps between symptoms of ADHD and autism, it should come as no surprise that a significant portion of people end up having both disorders. In fact, there is a specific term which is applied in this situation. When someone meets the diagnostic criteria for both autism and ADHD, they have AuDHD.

It actually wasn’t until 2013 that the Diagnostic and Statistical Manual of Mental Disorders recognized a dual diagnosis of ADHD and ASD. That was an important change, especially considering how frequently this comorbidity occurs. Estimates state that about 20% to 50% of children with ADHD also meet the criteria for autism, while approximately 30% to 80% of children with autism also meet the criteria for ADHD. Adults can have AuDHD as well, though it’s not as common as it is in children.

People who have both ADHD and autism need to work closely with their healthcare providers to come up with a personalized treatment plan. Someone with both conditions will have to confront more serious obstacles in their day-to-day life compared to an individual who has just one of the two disorders. If you’re concerned about the possibility of having ADHD, autism, or AuDHD, Done can help. Our experienced, licensed clinicians can provide ADHD assessments and treatments. For those who don’t receive an ADHD diagnosis, we can help direct you to the best resources to get the help you need.