Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD) are similar in many ways, which is why it can be hard to tell one from the other. However, there are important differences between the two.
Knowing what makes one condition different from the other will help you evaluate whether you have ASD or ADHD, or perhaps an altogether different condition.
Here is a list of important differences between Autism Spectrum Disorder (ASD) and ADHD. I will use the words “child” or “children” in this list, but the characteristics of those who have ASD or ADHD apply equally to both children and adults
Children with Autism Spectrum Disorder tend to focus on only one activity at a time, and they focus on that activity intensely with little regard for anything else going on around them. They are hyper-focused rather than unfocused.
Children with ADHD, on the other hand, engage in multiple activities at the same time, they are easily distracted and jump from one interest or activity to another. They can’t focus on one thing for very long, the opposite of hyper-focus.
Children with ADHD will do things without considering outcomes. They act immediately, have trouble waiting for things and find it hard to wait for their turn. They interrupt, blurt out comments, and seem unable to restrain themselves.
Children with Autism Spectrum Disorder think through their actions more carefully. They can tolerate waiting. They may interrupt and say things without regard for what else is going on but it is because they don’t understand how conversations are carried out rather than not being able to restrain themselves.
Difficulty interpreting non-verbal communication and subtle aspects of people related to each other is characteristic of children with Autism Spectrum Disorder. They confuse behaviors that may be appropriate in one setting from those that are appropriate in another setting, so that they often act inappropriately for the situation they are in.
They find it hard to interpret what facial expressions and body posture mean, and they have particular difficulty understanding how people express their emotions.
Children with ADHD understand social situations much more accurately and they engage much easier in social situations even though they are easily distracted and often not observant of what’s going on around them. Unlike those with Autism Spectrum Disorder they can consider what other people are thinking much easier and they can participate in the give-and-take of social interactions more readily. They tend to be more socially driven than children with Autism.
Children with ADHD do not tend to have specific weaknesses in their understanding of and use of language. They readily understand when a statement such as, “it’s raining cats and dogs” is being used as a figure of speech and not as a literal statement. They also speak with a normal tone of voice and inflection.
In contrast, children with Autism Spectrum Disorder often have difficulty understanding non-literal language, slang or implied meaning. The phrase, “it’s raining cats and dogs” is perplexing as they don’t immediately understand why dogs and cats would be raining.
They tend to talk a lot and have more one-sided conversations that have to do with topics of interest to them. They have a hard time taking turns in conversations or talking about a topic of interest to someone else.
Children with ADHD tend to express their feelings directly and fairly clearly whereas those with Autism Spectrum Disorder do not generally show a wide range of emotions. When they do communicate their feelings often they are out of synch with the situation that generates the feeling. They tend to be more brittle and fragile, falling apart easily when things don’t go their way.
6. Sensory Differences
Children with ADHD tend to process sensory input in a typical manner as their peers. They may have preferences for how they handle sensory input like music, touch, sounds in general, visual sensations but generally the way they handle these sensations are much like other children.
In contrast, children with Autism Spectrum Disorder have more specific preferences in the kind of sensory input they like or dislike. They may be overly sensitive to one kind of sensation and avoid that persistently. Or they may prefer a certain type of sensation, certain kind of music for example, and seek it out over and over. Overall, they tend to get more easily overloaded with sensory input than children with ADHD.