Background Obsessive-compulsive disorder (OCD) is a disorder of automatic,
uncontrollable behaviors and obsessive rumination. There is evidence that OCD patients
have difficulties performing goal-directed actions, instead exhibiting repetitive stimulus-
response habit behaviors. This might result from the excessive formation of stimulus-
response habit associations or from an impairment in the ability to use outcome value to
guide behavior. We investigated the latter by examining counterfactual decision making …