Reversal learning in patients with obsessive-compulsive disorder (OCD) and their unaffected relatives: Is orbitofrontal dysfunction an endophenotype of OCD?

It has been suggested that reversal learning deficits might be an endophenotype of OCD. To investigate this hypothesis, we administered a probabilistic reversal learning task (ProbRev) to OCD patients, their unaffected first-degree relatives, and healthy controls. Although the relatives had a performance in between OCDs and controls at the early phase of the ProbRev, their performance was similar to controls and was significantly better than OCD patients at the later stages of the test. Our findings imply that reversal learning impairment might be partly a trait-related feature of OCD but state-related factors can also contribute to observed deficits.