If a child who's simply very active is mistakenly diagnosed with Attention Deficit Hyperactivity Disorder (ADHD), they can end up on pharmaceuticals such as Ritalin unnecessarily. The problem is, it can be quite difficult to determine if someone actually has ADHD, and misdiagnoses are common. Now, however, researchers from Tel Aviv University have announced that analyzing a patient's eye movements may be the key.
In an experiment conducted at the university, two groups of 22 adult subjects took an ADHD diagnostic computer test called the Test of Variables of Attention, or TOVA. The first group, all of whom had previously been diagnosed with ADHD, took the 22-minute test twice – once unmedicated, and once after taking their ADHD-suppressing methylphenidate.
The second group did not have ADHD, and served as a control.
It was discovered that the ADHD group was significantly and consistently less able to suppress eye movement in anticipation of visual stimuli during the first tests. Additionally, however, the researchers noted that once those subjects took their medication, their level of involuntary eye movement was reduced to that of the control group.
"This test is affordable and accessible, rendering it a practical and foolproof tool for medical professionals," said team member Dr. Moshe Fried. "With other tests, you can slip up, make 'mistakes' – intentionally or not. But our test cannot be fooled. Eye movements tracked in this test are involuntary, so they constitute a sound physiological marker of ADHD."
Larger trials are now being planned.