Locating Biomarkers of Obsessive-Compulsive Disorder Through the Use of Behavioral Tasks: Protocol DevelopmenttextLohman, Connor RaycreatorMcLaughlin, NicoleAdvisorGreenberg, BenjaminReaderBorton, DavidReaderBrown University. Division of Biology and Medicinesponsor20199, 74 p.born digitalThesis (Sc. M.)--Brown University, 2019thesesPatients who undergo deep brain stimulation (DBS) of the ventral capsule/ventral striatum (VC/VS) for intractable Obsessive-Compulsive Disorder (OCD) have approximately a 60% reduction in symptom severity in general ​(B. D. Greenberg et al. 2010)​. However, there are still negative DBS-induced behavioral side effects. One of the most important areas in which current DBS treatment is lacking is the inability to quickly react to phasic changes in both positive (hypomania) and negative (OCD-triggered distress) valence states. Adaptive (or “closed loop”) DBS systems would solve this problem by recording, stimulating, and using predetermined signals from the brain to make adjustments to patients’ behavior as it happens in real time. The only issue is the lack of reliably known biomarkers that can indicate these changes (or other physiological correlates of OCD and associated symptoms) are happening. The goal of this study is to accurately classify the acute fluctuations in OCD-related distress that will help to locate the biomarkers of change during the negatively valenced state. We plan to locate these biomarkers through a series of tests during which we record patients’ affective states through neural and video recordings while provoking their OCD symptoms. This should help us to distinguish such states from other affective states which might not require any changes in stimulation levels. Along with OCD-related distress, we will also be looking for state changes related to elevated or depressed mood and nonspecific anxiety which may also require an adjustment in stimulation. This paper describes the process of developing a unique provocation task intended to delineate such biomarkers, using EEG, as well as the experimental protocol and materials used to measure the relevant state changes.behavioral neuroscienceObsessive-compulsive disorderEnglishRPB2019060310.26300/th1j-gr37In CopyrightCollection is open for research.