While the two neuropsychological disorders may seem like two sides of the same coin — as both seem to manifest similar hyperactive symptoms — researchers are quick to dispel the idea that ADHD (attention deficit hyperactivity disorder) and OCD (obsessive compulsive disorder) belong lumped together, as the consequences of medicating them similarly can prove disastrous, especially for children.

While ADHD is characterized by short attention span, loose focus, and recklessness, OCD exhibits symptoms of intense repetition, calculated — even paralyzing — decision-making, and over-consideration of consequences. And while ADHD is medicated with Ritalin, a psychostimulant, giving a child with OCD the drug could only exacerbate his or her symptoms.

In one study, researchers from Tel Aviv University examined 30 subjects with OCD, 30 with ADHD, and 30 with no psychiatric diagnosis to act as the control. The purpose of the study was to compare the effects of each disorder against a standard set of questionnaires and cognitive tests.

All participants were male, with a mean age of 30 years old.

As expected, the OCD/ADHD groups performed worse on the tests than the control group. The ADHD group exhibited more impulsivity than the other two groups, and the OCD group did not perform significantly different than the control group. However, the OCD group did report a bias in their perceived levels of impulsivity.

"Moreover, a negative association between OC symptoms and response inhibition and a bias in self-perception of impulsivity was found only in the OCD group," the researchers noted, suggesting that people with OCD tend to overestimate their impulsivity by measuring it according to an abnormally high threshold.

Co-author of the study, Prof. Reuven Dar of TAU's School of Psychological Sciences, argued that these findings highlight the ease with which many children can get misdiagnosed for the wrong disorder. OCD's compulsive behavior could be seen as ADHD's fidgeting, for instance.

Dar points out that OCD diagnoses are less common, in part because of a vicious circle of diagnosis and also that ADHD has become more popularized; therefore, its symptoms seem more pronounced.

If diagnosed incorrectly, a child's future path could be fraught with unnecessary medication and psychological problems stemming from self-esteem issues and behavioral disorders.

"It's more likely that a young student will be diagnosed with ADHD instead of OCD because teachers see so many people with attention problems and not many with OCD," said Dar. "If you don't look carefully enough, you could make a mistake."