PROVOC will be used to evoke manageable levels of OCD related distress. Three tasks will be developed collaboratively with the participant and independent evaluator that involve the participant being exposed in vivo to triggers that are considered by him/her impossible to confront without ritualizing. Each of the 3 tasks will be broken up into 7 steps, which provoke increasing levels of distress when encountered. Each step will be uniform in duration (i.e., one minute exposure) with the potential of 7 one-minute tasks with ~30 seconds break between steps, to provide brief rest for the patient and introduction of the next task. Participants will systematically confront triggers without ritualizing starting with easier items, and will continue until they feel their distress or need to ritualize is intolerable. This task will involve researchers and subjects deciding upon a few different triggering items (bloody (fake) napkin, used tissue, etc) that will be moved closer and closer to the subject as they wear the EEG measuring system. Each step should take one minute or less, and the subject will always have the option of stopping if the task becomes too distressing. There will also be a similar process involving objects that should not cause any distress to be used as a control. Consistent with prior research, 5 scores are calculated including percentage of steps completed, subjective units of distress (SUDS) across steps, avoidance, ritual engagement, and composite provocation score, which will be associated with changes in biosignature from brain recordings. We will pilot the provocation protocol, and start addressing problems that come up (e.g. EEG movement artifacts). Sessions will be videotaped with AFAR system concurrent to recording of LFPs from VS and scalp EEG.