Assessing attention deficit by binocular rivalry

Objective: To determine whether the frequency and duration of the periods of suppression of a percept in a binocular rivalry (BR) task can be used to distinguish between subjects with attention deficit hyperactivity disorder (ADHD) and controls. Method: 122 participants (6 to 15 years) were assigned to three groups: ADHD Combined (ADHD-C), ADHD-Predominantly Inattentive (ADHD-I) and controls. They each performed a BR task and two measures were recorded: alternation rate and duration of exclusive dominance periods. Results: ADHD-C group presented fewer alternations and showed greater variability than did the control group; results for the ADHD-I group being intermediate between the two. The duration of dominance periods showed a differential profile: in control group it remained stable over time, whereas in the clinical groups it decreased logarithmically as the task progressed. Conclusions: The differences between groups in relation to the BR indicators can be attributed to the activity of involuntary inhibition