The diagnostic bible for psychiatry was updated in 2013—it was the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), and it marked the first time that a person could be diagnosed with both ADHD and autism. “The conditions themselves look very different on paper, but there’s confusion between the two of them because they can sometimes co-exist,” says Elisa I. Muniz, MD, assistant professor of pediatrics at Albert Einstein College of Medicine in New York City. “In kids with ADHD, 14 percent have autism, and for autistic children, it’s estimated that up to half have ADHD.” According to the Centers for Disease Control, it’s estimated that 11 percent of children in the U.S. have the condition, while 1 in 59 children has autism.
We asked our experts to show us certain scenarios in which these two common—and often intertwined—conditions differ:
Someone with ADHD can make friends easily—but often wants to overrun them at the same time. “A child with ADHD is the type who interrupts, invades personal space, and can often be bossy,” says Deborah A. Pearson, PhD, professor of psychiatry and behavior sciences at Louis A. Faillace, MD, Department of Psychiatry and Behavioral Sciences at UTHealth in Houston, Texas. Autistic children, on the other hand, are happy to watch from the sidelines. “Or they’ll do parallel play, playing on the side of other children without wanting to be a part of the group, and they may even avoid other children,” says Dr. Pearson. Lack of eye contact, inability to read social cues and hold conversations are other hallmarks of autism.
Energy levels and focusing issues
The classic high energy level of someone with ADHD differentiates them from someone with autism. “Those with ADHD are so hyperactive that it seems like they have a battery that doesn’t stop running,” says Dr. Muniz. “They can be impulsive and do things without thinking, more than another person would. They’re easily distracted and have trouble sustaining their attention, so they may start something and then stop because they need more breaks than the average person.” Girls are often underdiagnosed for ADHD, in fact, because they don’t always have those classic hyperactive qualities.
A main symptom of autism is an extreme sensitivity to tastes, smells, textures, sounds—they are especially sensitive to loud noises. “Some autistic children even need tags cut out of their clothes because they can’t tolerate it,” says Dr. Pearson. “On the other hand, those with ADHD aren’t sensitive at all to loud noises, textures, tastes.” Discover other autism symptoms you may not realize.
Here’s where the two conditions’ differences can be very apparent: Autistic children are very precise and hyper-organized—making sure there’s a place for everything and everything in its place—whereas someone with ADHD struggles with organization. “Autistic children will actually get very upset if their toys are not organized in a particular way, and god forbid if you put the pink bunny and put it where the blue elephant was supposed to be. They are very exact about things, usually obsessively so,” says Dr. Pearson.
Interests and hobbies
Someone with ADHD may have a bunch of varied interests, whereas those with autism will show a restrictive, hyper-focused interest on one particular topic. “Their interests are very specific,” says Dr. Muniz. “Say a child with autism takes an interest in trains. They will be able to tell you the names and stops of every train line, and only want to talk about that topic. That’s called a restrictive interest.”
While both conditions develop in childhood, it’s evident earlier in children with autism. “In a child with ADHD, speech development is pretty much on track. Those kids are developing speech pretty normally, but in autism, speech is often delayed, and in some cases, we don’t see it at all,” says Dr. Pearson. Discovering that your child has autism can be alarming at first; learn what you should never say to a parent of autism.
Just as with speech, other areas of early development may look different with autistic children versus those with ADHD. “Many of my parents of autistic children say they knew something was different early on,” says Dr. Pearson. “I had one parent, for example, who said ‘when he was a baby he wouldn’t look me in the eye.’ On the other hand, ADHD doesn’t usually become evident until they’re going to preschool and are compared to other children.” Determine whether your child is just energetic or may have ADHD.
“Those with ADHD display pretty typical nonverbal behavior—they make good eye contact, use gestures, and have a normal range of facial expressions, but in autism, this isn’t the case,” says Dr. Pearson. “With autism, you’ll see inconsistent or nonexistent eye contact, they may not use gestures, and they may have a limited range of expressions or may have either very exaggerated or neutral facial expressions.” (Learn about the one eye test that can detect autism.)
Experiencing something new
While someone with ADHD seems to constantly be jumping from one thing to another, those with autism are the opposite and can find new experiences anxiety-provoking says Dr. Pearson. “Anything that’s out of the routine can be very upsetting to them, even the smallest changes can cause a big upheaval.” Watch out for these persistent autism myths.