Well, are they? I’m asking for a friend.

Actually, I’m asking for a group of researchers in the Netherlands who just did a study that raises questions about whether sensory symptoms should be considered as diagnostic criteria for ADHD.

Sensory symptoms are most commonly associated with autism spectrum disorder (ASD). Incidentally, it’s not unusual for people who have either ADHD or ASD to also have the other. And it turns out that many people with ADHD may have sensory symptoms without having ASD.

TouchSensory symptoms come in two basic flavors. One is sensory hypersensitivity, which is exactly what it sounds like. People with sensory hypersensitivity are especially sensitive to sensations that don’t typically bother others.

On the other hand, people with sensory hyposensitivity are less sensitive to some types of sensory input. For example, they may seek out sensory stimulation or be less sensitive to pain.

So, back to that study. The researchers surveyed 116 adults with ADHD, asking them about their ADHD symptoms, their sensory symptoms and their autistic symptoms.

Comparing the people with ADHD to a group without the disorder, the researchers found that those with ADHD were more likely to have both sensory hypersensitivity and hyposensitivity. Moreover, how likely the ADHDers were to have sensory symptoms correlated with how severe their ADHD symptoms were in general.

The people with ADHD were also more likely to have autistic symptoms, but this didn’t explain the relationship between ADHD and sensory symptoms. In other words, if people with ADHD have more sensory symptoms, it’s probably not just because they have more autistic symptoms.

ADHD and sensory symptoms were especially closely intertwined for women. In fact, 43 percent of the women with ADHD experienced sensory hypersensitivity or hyposensitivity. Meanwhile, 22 percent of men experienced at least one of the two.

OK, so much for the science. Now for my personal take on this.

I think the idea that ADHD can be associated with being either oversensitive or undersensitive to sounds, touch, etc. is interesting because anecdotally, it does seem that ADHDers often go to one extreme or the other in their tolerance for sensory stimulation.

For example, one ADHD coping strategy I talk about on here is using sensory stimulation to help with focus. Things like listening to music while you work or even just working in a public place can keep the ADHD brain stimulated and help with concentration.

On the other hand, I’m also aware that some people with ADHD need absolute silence to work and get distracted by even the smallest sounds. And I expect that others with ADHD can have both an abnormally high need for “background noise” in some situations and an abnormally low tolerance of it in others.

From that observation, it doesn’t seem like too much of a stretch to say that ADHD people are prone to processing sensations atypically in one direction or the other (too sensitive or not sensitive enough).

What’s less clear is how the cause-and-effect works. Do the executive functioning problems that come with ADHD create the sensory symptoms? Or do the sensory symptoms actually contribute to the other problems? There’s some revealing scientific work to be done here, which is one of the points the authors of the study made too.

In the meantime, I’d be very curious to hear about your experiences with ADHD and sensory hypersensitivity or hyposensitivity. D’you experience sensory symptoms, and if so, how do they interact with your ADHD symptoms? It would be interesting to get some different perspectives on this.

Image: Flickr/Roberto Gama