Attention Deficit and Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) are unrelated conditions, much like depression and anxiety are two separate disorders. Indeed, the official manual of psychiatric disorders, the DSM-IV, does not recognize any overlap between ADHD and ASD.
Yet both disorders share many similar symptoms and experienced ADHD psychologists and Autism psychologists regularly cannot see a clear boundary separating them.
Recent evidence suggests that some of the same genetic influences affect the development of both ADHD and ASD. They ordinarily respond to the same treatments. And 60-70% of children diagnosed with ASD have symptoms consistent with ADHD.
For these reasons and others, it is important to understand and appreciate how the two conditions are similar. In fact, knowing these similarities often is more important than recognizing their differences.
Studies have shown that children with ADHD and those with Autism Spectrum Disorder have similar difficulties with executive functioning, a term referring to the mental processes involved in planning, paying attention, problem solving, task switching and mental flexibility.
Inattentiveness, distraction and impulsivity result from difficulties in executive functioning in both ADHD and ASD. Children and adults with ADHD or ASD:
- Have problems following directions
- Repeat the same errors when learning
- Behave impulsively, without considering the consequences of their actions
- Don’t give close attention to details and make careless mistakes
Children with ADHD, Autism Spectrum Disorder (ASD) or both may act in ways that interfere with making friends. They say inappropriate things, intrude on others and are impatient.
They tend to be highly active and have difficulty slowing down. Reading what other people are thinking and/or feeling based on their facial expressions, gestures and other nonverbal signals is challenging, and they rarely make eye contact. When spoken to, they don’t appear to listen. They often don’t understand what is socially inappropriate, inadvertently insulting and turning off others.
They tend to avoid playing and socializing with others. Because of their difficulty with social communication, children with ADHD or ASD often develop anxiety and low self-esteem, further complicating their social relationships.
Children with ASD or ADHD regularly have learning disabilities that require evaluation and special education support. Up to 30% of children with ADHD have a specific learning disability while 51% of those with Autism Spectrum Disorder have a non-verbal learning disability.
Both groups of children tend to have poor organizational skills. They work impulsively and make careless mistakes. They are also slow readers and lack awareness of time.
Many children who have ADHD or ASD also have a sensory processing disorder (SPD) that makes them sensitive to certain sensations, such as flickering lights, smells, touch and sounds. This contributes to distractability because they are so busy noticing background events that they are unable to focus on what they were originally doing.
Another symptom of SPD is poor body awareness. People with SPD may not realize they are sitting too close to someone. They bump into others because they misjudge distance, and they often break things because they don’t know how much force to use. These sensory related difficulties impact relationships and academic performance.
A Final Consideration
Children and adults with ADHD or ASD or both share many characteristics, yet describing these similarities implies generalizations. There is always the person who is the exception. Mental health professionals, including ADHD psychologists and Autism psychologists, recognize the uniqueness of each individual.
Whatever their diagnosis, the person with ADHD and the person with ASD must each be thought of as an individual with unique and different characteristics. Inside, each is a person who needs tolerance, our informed understanding, our thoughtful interventions, our patience and our love.