OCD PATIENTS SHOW INCREASED CERTAINTY SEEKING IN AN OPERANT OBSERVING RESPONSE TASK: A TRANSLATIONAL APPROACH

Abstract Obsessive Compulsive Disorder (OCD) has been linked to numerous cognitive theories, such as increased intolerance of uncertainty. Certainty seeking may be one process underlying excessive checking behavior. We sought to obtain objective and quantitative measurements of certainty seeking behaviors in patients in a translational task. A rodent version of the observing response task has previously demonstrated excessive checking under chronic quinpirole administration [1] . We tested 21 OCD medicated patients that did not have any comorbid disorders, and 21 age and gender matched controls on this novel operant paradigm. Participants pressed two buttons in order to earn rewards on two corresponding variable ratio schedules. At any one time, only one of the buttons is ‘active’ thereby leading to rewards. Importantly, participants could press a third, ‘observing’ button that always cued the currently active button. In the baseline phase pressing on the ‘inactive’ button resulted in no rewards being earned, in a subsequent phase, pressing on the ‘inactive’ button resulted in punishments being delivered on a variable ratio schedule. Patients with OCD pressed the ‘observing’ button more than controls in during baseline and avoided pressing the inactive button to a greater degree. When the inactive button pressing was punished, the patients did not differ in their observing responses but now healthy controls pressed the observing button significantly more, reaching the level of observing responses exhibited by the patients. Patients reported greater anxiety during the task, but did not significantly differ on amounts of rewards or punishments obtained. In sum, greater certainty seeking was found in OCD patients, as captured by the increased observing button pressing during baseline. The results further indicated that in contrast to healthy controls, the patients were insensitive to any actual negative consequences of being uncertain. This study is consistent with the notion that increased intolerance of uncertainty could contribute to clinical symptomatology. Moreover, the results provide validation for this translational paradigm reinforcing the rodent version.