Autism Traits in Adults with ADHD: Fixations, Routines, Stimming
My husband once explained to me, in pain-staking detail, why J. R. R. Tolkien excised every French word from The Lord of the Rings saga, down to swapping “Bag’s End” for the French-derived “cul-de-sac.” The explanation lasted 45 minutes; I know because I counted each one. My husband owns multiple copies of every Tolkien book ever written, and most authoritative texts on his life and works. Mention Denethor in passing (somehow, it’s happened), and he’ll ask, “Do you mean the Steward of Gondor in The Lord of the Rings, or the 10th Steward of Gondor, or the elf?”
His psychology professor once told him, “You’re not on the [autism] spectrum. But you’re not not on the spectrum.” In other words, my husband has ADHD, which was diagnosed late in life; he certainly does not have autism. However, his ADHD manifests many traits that some consider autistic.
Obviously, not every person with ADHD will exhibit traits associated with autism — and while “up to a quarter of children with ADHD have low-level signs of ASD, which might include having difficulty with social skills or being very sensitive to clothing textures, for example,” sharing some traits with autism is not the same as having autism. I’ll repeat it for the people in the back: my husband does not have autism. Claiming a neurodiversity you don’t have is gross.
We can keep going now.
How Our ADHD Sometimes Looks Like Autism
Like 10 to 20 percent of people with ADHD, my husband has been diagnosed with dyscalculia, a learning difference related to math. By his own admission, he masks, or imitates other people’s social cues, facial expressions, and gestures, all the way down to handshakes. He “fixates on specific interests” (obviously, Tolkien) and, despite his ADHD, he tends toward a rigid schedule in which he vastly prefers that the same things happen at the same time every day.
[Self Test: Autism Test for Adults]
I’ve also been diagnosed with ADHD, and like my husband, I exhibit many traits associated with autism (no, I do not have autism. I would never claim to have autism. That would be gross and deeply offensive to my friends with autism or who self-identify as autistic). Like my husband, I mask. I tend toward fixations: The Magicians, which I used to live-tweet. Once, my husband made vanilla coffee in the morning. I glared over my mug and told him, “You’re going to become a podcast if you do this again.”
I also have trouble with “social emotional reciprocity,” which is a really fancy way of saying that I interrupt people a lot; I monologue; and I have trouble with peopling in general. I stim: did you know that obsessive cuticle-picking counts? I didn’t. I also have trouble with sensory overload and would happily eat my husband’s vegetarian chili every single night for the rest of my life.
The ADHD-Autism Connection
It shouldn’t come as a shock that two people with ADHD show traits associated with autism. A recent study of children with ADHD and children with autism found that “children with abnormal white matter nerve bundles are more likely to demonstrate more severe symptoms of either ADHD or ASD.” Brain scans showed that “structural abnormalities in the brains’ white matter nerve bundles were associated with more severe symptoms of both ADHD and ASD,” and these structures were related to the part of the brain related to communication.
Knowing these commonalities are normal offshoots of ADHD has helped us both tremendously. It’s that same lightbulb: “Oh, I’m not [insert negative self-talk that’s been drummed into me by years of people judging my behavior]!” Both my husband and I were diagnosed as adults, and it’s deeply reassuring, for me at least, to know that my tendency toward strange fixations is 100% normal for my neurodivergent brain.
[Read: The ADHD Brain – Neuroscience Behind Attention Deficit Disorder]
“Oh my gosh, how do you wake up every single day at 5 am and write?” people always ask me. Then their faces drop into confusion. “Wait,” they’ll say. “You mean you do it on weekends, too?” I never knew what to say, because I simply do it; I’ve done it for a decade now. If I don’t wake up and write at 5, the day feels strange and wrong. I finally understand why. My ADHD brain insists on that daily sameness—a sameness often needed, to a greater degree, by people with autism.
This knowledge has also helped me understand that my occasional meltdowns are sensory overload. There’s a solid neurological reason why my son’s incessant clicking noise might drive me over the edge, and why a brotherly shove or shout might send me fleeing. I hate loud movies; my husband thinks that films should shake the foundations. I’ve often stopped on our stairs, looked at the TV screen, and turned right around again.
Now he understands why that happens and why, when I appear, he has to turn it down.
Sometimes, it seems like childhood was one long stretch of the world shouting that I was weird, and adulthood has been a long road of realizations that wait, no, I’m not weird—and neither am I [insert negative self-talk about laziness, spaciness, time-management, messiness, a need for sameness, etc.]. Unwinding those ugly beliefs has taken a lot of time and therapy. Knowing that my ADHD can manifest traits associated with autism has handed me another piece in that puzzle.
Life makes so much more sense. I’m not the weird kid anymore. I’m a person whose ADHD shares some traits with autism. Maybe it seems small. But it points me in an important direction; it helps me to understand why I do what I do, and as a neurodivergent person, better ways to cope with a world designed for neurotypical people.
Score one for the former weird kid.
Autism Traits in Adults with ADHD: Next Steps
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