Attention deficit hyperactivity disorder (ADHD) is a condition that impacts the lives of people young and old, across the country and around the world. Afflicting more than seven percent of school-aged children and as much as five percent of adults, ADHD is associated with behavior disorders, learning disabilities, hyperactivity, and the inability to concentrate (Antshel et al., 2011). ADHD can interfere with social and interpersonal relationships and pose serious challenges to academic achievement and job performance.
ADHD is one of the most common childhood disorders, yet confusion about its causes and implications abounds. Conventional wisdom says that children displaying symptoms of ADHD are likely less intelligent than their peers. In the same way, the stigma associated with ADHD reinforces the unspoken idea that smart kids can’t possibly be afflicted with such a syndrome.
ADHD and IQ
While it has been established that ADHD affects children and adults at every IQ level, some have suggested that ADHD patients with above average intelligence often achieve success that is out of reach for those with lower IQs (Arnold, et. al., 2010). ADHD is associated with positive attributes, such as creativity, a drive to achieve, a tendency toward entrepreneurship, and “out-of-the-box” thinking (Arnold, et. al., 2010).
The relationship between ADHD and IQ has become a topic of interest in the scientific community. Intelligence is a complicated human quality, and attempts to locate its foundation remain controversial. While standardized IQ tests are widely accepted guidelines for comparing individual aptitude, efforts to isolate intellect in the brain—and in our genetic code—have yielded mixed results.
The search for the source of smarts has linked intelligence to particular genes, but recent studies are not yet backed by scientific consensus (Rizzi, et. al., 2010). Scientists do agree, however, that ADHD and intelligence are highly dependent upon genetic inheritance, and may share influence in specific parts of the brain (de Zeeuw, et. al., 2012, Rizzi, et. al., 2010).
Recently, researchers hypothesized that changes in the brain associated with ADHD may vary according to the patient’s IQ. Examining 214 children ages six to 15, one study focused on areas and qualities of the brain known to correlate with ADHD. They found an association between IQ and ADHD but, as expected, the relationship between them was not so cut and dry (de Zeeuw, et. al., 2012).
The analysis showed that while ADHD correlates with intelligence, children with ADHD and above average IQ have global reductions in brain volume. Alternatively, ADHD children with below average IQs suffer from a delay in the brain’s cortical development (de Zeeuw, et. al., 2012). So, while ADHD impacts the brains of those with low and high levels of intelligence, it appears to affect them in different ways.
Intelligence and Impaired Executive Functions
Clinical interviews suggest that smarter ADHD patients may actually suffer more setbacks than their less intelligent peers. A recent study focused on executive functions that most of us take for granted. Impairments in executive functioning lead to distractibility, impulsiveness, and poor concentration, and can impact memory and organizational skills. 157 adults with ADHD and IQs greater than 120 were assessed according to eight measures of executive functioning (Brown, Reichel & Quinlan, 2009).
The study showed that executive function impairments are more common in high-IQ ADHD patients than in the general population. In fact, ADHD patients showed significant impairment in all eight measures of executive function compared to the average person. The results revealed that even ADHD patients who excelled in tests of language, memory, and perception had difficulty performing daily tasks (Brown, Reichel & Quinlan, 2009). Later studies have validated these results; they show that ADHD adults with high intelligence levels performed less well on executive function tests than their healthy, high-IQ counterparts (Antshel, et. al., 2010).
Are Smart ADHD Sufferers Stigmatized?
ADHD patients with high IQs also report the effects of a kind of reverse stigmatization that defined their childhoods. Children with ADHD often excel in particular activities that allow them to focus, such as computer gaming or piano playing (Brown, Reichel & Quinlan, 2009). This single-minded passion for specific activities accompanied by sub-par academic achievement was interpreted as laziness. For many, this resulted in delayed diagnosis and treatment of their ADHD symptoms. (Brown, Reichel & Quinlan, 2009).
For bright kids with ADHD, parents and teachers tend to assume the problem is their motivation or will power. These presumptions can follow patients throughout their childhoods and seriously impact their education. Of the ADHD patients interviewed, more than 40 percent had dropped out of post-secondary school despite having IQs of 120 or higher (Brown, Reichel & Quinlan, 2009).
While intelligence and ADHD are intertwined, their relationship is complex and generally misunderstood. For patients suffering from the physical and social impacts of ADHD, extra smarts do not afford them any added perks; in fact, a high IQ may actually make living with ADHD even more challenging.