Too Smart for ADHD?

Talk to 10 ADHDers who weren’t diagnosed until adulthood and you’ll hear ten stories of people who slipped through the cracks because they didn’t fit the stereotypical profile of the ADHD kid in some way or another.

Maybe they were shy and reserved, so they didn’t seem like the disruptive, hyperactive kids from hell many people envision when they think about ADHD.

Maybe they were female. ADHD is sometimes seen as a disorder of rambunctious boys, and too often gender alone can still be a disqualifying factor for an ADHD diagnosis.

And maybe they were just too smart to have ADHD. To the extent that higher-than-average intelligence can compensate for the impairments that come with ADHD, intelligent ADHDers can slip under the radar. After all, the idea of someone having a high IQ and an “attention deficit” at once does seem a little paradoxical.

And for the same reason intelligent ADHDers can be harder even for trained professionals to spot, intelligence can be a barrier preventing the ADHDers themselves from gaining insight into their condition. Highly intelligent ADHDers are prone to thinking of themselves simply as lazy or, yes, stupid, and are subject both to the self-doubt that living through years of undiagnosed ADHD can engender as well as that insidious kind of doubt that many ADHDers know all too well — doubt in their diagnosis itself.

It doesn’t make things easier that there has been debate even in the medical field about how meaningful ADHD is as a diagnosis for those with high IQs. Over the last decade or so, however, researchers have been looking increasingly carefully at how ADHD plays out in those with above-average intelligence. Their findings suggest that ADHD still wreaks damage on the lives of those with high intelligence and that intelligent children and adults with ADHD differ in several interesting ways from their neurotypical counterparts.

In other words, no matter how smart you are, you probably aren’t too smart for ADHD.

High intelligence makes ADHD harder to diagnose…

ADHDers with above average intelligence are more likely to fly under the radar and less likely to fit the stereotypical ADHD profile, but these aren’t the only reasons intelligence gets in the way of recognizing ADHD. Highly intelligent people with ADHD have different strengths and weaknesses that make traditional ADHD diagnostic tools less effective.

Take the TOVA, for example. If you’ve been in for a neuropsychological workup, you’ve probably encountered this delightful diagnostic tool — it involves spending about 20 minutes repeatedly pressing a button when you see a certain type of visual input or hear a certain type of sound and not pressing a button when you don’t see that type of visual input or hear that type of sound. It is literally designed to be the most boring computer game ever. Not because the people who made it are sadists, but because ADHDers don’t handle boredom well, so making people really bored is a good way of seeing whether they’ve got ADHD.

The problem, though, is that for those with ADHD and above-average intelligence, the TOVA’s special flavor of diagnostic torture just doesn’t work as well. A 2003 study found that children with higher IQs were more likely to get false negatives on the TOVA and that among gifted children, the TOVA was only able to pick out 9.4% of the ADHDers.

More generally, tests of executive functions that work reasonably well for diagnosing ADHD in those with average intelligence seem to be less reliable for those with higher IQs. A 2002 study looked at how people performed on 5 different tests of executive functioning and found that in the group with average IQ, 3 of the 5 tests were useful for distinguishing between ADHDers and non-ADHDers while in the group with above-average IQ, 0 out of 5 tests were helpful.

So highly intelligent people are probably less likely to be referred for diagnosis in the first place since they’re more able to sort of muddle along without getting in too much trouble, but even when they do get referred, many of the tests medical professionals use to look for ADHD don’t even work on them!

…but highly intelligent people can still have ADHD

If highly intelligent people with ADHD do OK on the TOVA and don’t bomb tests of executing functioning as often as other ADHDers, it’s reasonable to ask whether ADHD is even a valid diagnosis for those with high IQs.

And that’s exactly what a team led by Kevin Antshel, a professor at SUNY Upstate Medical University did in a study published in Psychological Medicine titled “Is adult attention deficit disorder a valid diagnosis in the presence of high IQ?

And, spoiler alert, the answer they came up with was “yes.” Comparing 53 ADHD adults with IQs of at least 120 and 64 equally intelligent non-ADHD adults, the study found that the adults with ADHD experienced wide-ranging and serious problems despite their high intelligence.

Overall, the ADHDers reported lower quality of life, did worse at work, received more speeding tickets, had more accidents and got arrested more often. They were also more likely to suffer from depression, OCD and anxiety, and to have first-degree relatives with ADHD. In other words, their high intelligence didn’t simply counteract the negative effects of ADHD; they still had a lot of problems.

Other studies have found that even though high intelligence can help compensate for ADHD on some measures of executive functioning, the functional problems Antshel’s study found still correspond to measurable executive functioning deficits. A 2009 study led by Thomas Brown found that ADHD adults with IQs of at least 120 are still much more likely than equally intelligent non-ADHD adults to score as impaired both on standardized cognitive tests and on self-report measures of executive functioning.

Taken together, these facts tell us that although highly intelligent people with ADHD can be harder to spot, they still have measurable deficits that wreak havoc on their personal and professional lives. There’s no such thing as “too smart for ADHD.”

Still, ADHD and high intelligence isn’t all bad

These studies paint a rather gloomy picture. Not only do intelligent ADHDers still have to put up with all the problems that come with the ADHD package, it’s also harder for them to get diagnosed. And it’s true that ADHD with high intelligence, or ADHD with any level of intelligence for that matter, isn’t exactly a walk in the park.

But there is somewhat of a silver lining — in a few areas, highly intelligent people with ADHD actually outperform their non-ADHD counterparts.

A 1991 study led Geraldine Shaw found that high-IQ children with ADHD actually score higher on tests of “figural creativity” (ie. visual creativity) than their non-attentionally-challenged high-IQ colleagues. A subsequent 1992 study by Shaw similarly showed that highly intelligent ADHD children use more imagery on average in general problem-solving tasks.

Both studies also found that high-IQ ADHD children tend to draw on a wider, less focused array of information while solving problems and rely more on implicit information and information outside of their conscious awareness — which helps explain why they might do better on creative tasks. Among the highly intelligent children, ADHD was also associated with several other traits including left-handedness, stimulation seeking and even allergies.

Probably there is a lot of interesting research yet to be done here. We know high intelligence can help compensate for some of the deficits associated with ADHD but not others and that high IQ + ADHD is a combo that can even confer advantages in some settings that require synthesizing information in an unpredictable, intuitive fashion. But we’re less clear on what exactly the defining characteristics of ADHD are in highly intelligent people and especially on what kinds of diagnostic tests would be useful for these folks.

One thing we do know for sure though: “too smart for ADHD” is a myth, and the sooner it goes away the better.

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