Previously, it has been argued that high intelligence “mimics” ADHD [10, 11]. According to this hypothesis, individuals with high intelligence frequently show high levels of activity, attention difficulties, and problems following rules and with task persistence [10,11,12,13].
Misdiagnosis is not uncommon when high IQ and ADHD collide. Very bright children who are also highly active are sometimes misdiagnosed with ADHD.
Children with ADHD who score poorly on IQ tests are often quite bright. Although academic tests sometimes suffer from the same problems as IQ tests (e.g., adherence to standardized rules) achievement test results often more accurately reflect the true functioning ability of children with ADHD.
High IQ may “mask” the diagnosis of ADHD by compensating for deficits in executive functions in treatment-naïve adults with ADHD.
ADHD AND GIFTEDNESS are sometimes described as having the same or similar characteristics. However, one diagnosis is considered a disability and one, a gift. Neither assumption is ideal in supporting the child identified with either ADHD, giftedness, or both, often referred to as twice exceptional or 2e.
Studies have shown that symptoms of bipolar disorder often overlap with those of ADHD, making it hard to diagnose both of these disorders. Bipolar disorder is marked by mood swings between periods of intense emotional highs and lows.
Some aspects of ADHD may also be symptoms of other conditions. Due to the complex nature of the condition, some people may receive an incorrect diagnosis. This is due to a wide range of diagnostic issues.
Overall, the study found that about 20 percent – or 900,000 – of the 4.5 million children currently identified as having ADHD likely have been misdiagnosed.
High-IQ adults with ADHD seem to function well, but it comes at a high emotional cost. They feel burdened and exhausted, blaming their struggles on themselves, not on their ADHD.
For instance, among the 18 studies under scrutiny that did not explicitly state an IQ cut-off point the mean range of IQ among individuals with ADHD reported in the studies is from 102 to 110. Given that lower IQ is associated with ADHD this suggests that individuals with ADHD may be inaccurately represented.
Executive functions have other roles which affect how someone thinks. In people with ADHD, these executive dysfunctions impact thinking in numerous ways. People with ADHD don't really think faster than people without it, but it can sometimes seem like they do. People with ADHD do think differently though, in a sense.
Masking is when a person with ADHD acts in a “socially acceptable” way to fit in and form better connections with those around them. This usually involves camouflaging their symptoms by controlling their impulses, rehearsing responses, and copying the behaviors of those who don't have ADHD.
ADHD is not overdiagnosed, but it may be often misdiagnosed. Sometimes people think ADHD is overdiagnosed because diagnoses have increased over time. It could be true that some diagnosed people do not really have ADHD. There are college students who fake ADHD to get medications that help them study faster.
Brain Differences
Doctors don't know everything about how ADHD works in the brain. But “imaging tests like MRIs show there are clear differences in people who have it and people who don't,” Alsakaf says. He points to the prefrontal cortex, a brain area that plays a role in behavior, problem solving, and emotions.
These include a thorough diagnostic interview, information from independent sources such as the spouse or other family members, DSM-5 symptom checklists, standardized behavior rating scales for ADHD and other types of psychometric testing as deemed necessary by the clinician.
Hyperactivity (talks a lot, fidgets, always on the go, etc.) Impulsivity (blurts out, interrupts, lies, angry outbursts, difficulty waiting, etc.) Inattention (forgetful, loses things, disorganized, makes careless mistakes, etc.)
Experts now consider ADHD to be on a spectrum, as each person can experience varying levels of symptom severity. There are also different types of ADHD, which cause different types of symptoms. When diagnosing ADHD, a doctor will use set criteria to determine the type and severity of ADHD.
Even when academic performance is high, the hidden cost of ADD (ADHD) is often taking a toll. Gifted students with ADD (ADHD) often struggle with anxiety, even when grades are high. They may suffer from boredom when required to do unnecessary, repetitive work that less gifted students may need.
A gifted child's IQ will fall within these ranges: Mildly gifted: 115 to 130. Moderately gifted: 130 to 145. Highly gifted: 145 to 160.
Signs of giftedness can appear as early as infancy and continue during the toddler and preschool years. Testing for giftedness and high IQ, however, usually takes place around age 5.