Autonomic Dysregulation in Obsessive–Compulsive Disorder: Simultaneous Assessment of Electrodermal, Cardiac, and Oculomotor Responses to Triggering Videos—An Exploratory Study

Background: The autonomic nervous system (ANS) in individuals with obsessive–compulsive disorder (OCD) is often characterized by heightened sympathetic tone and reduced parasympathetic flexibility. This exploratory pilot study aimed to provide a detailed, dynamic portrait of autonomic dysregulation. Methods: Heart rate variability (HRV), galvanic skin response (GSR), and oculomotor measures (pupil size, fixations, saccade velocity) were recorded in 31 participants with OCD (obsessive–compulsive disorder) and 46 healthy controls while viewing 18 videos, half of them designed to trigger specific OCD dimensions and half neutral or positive. Results: The OCD group exhibited a state of sympathetic hyperactivation, evidenced by significantly lower mean NN intervals (average interval between normal heartbeats) and a distinct GSR (galvanic skin response) pattern marked by a rising tonic component across the experiment. Healthy controls exhibited increases in SDNN (standard deviation of NN intervals) and RMSSD (root mean square of successive differences) following pleasant videos, whereas this response was less pronounced and emerged later in the OCD group, suggesting reduced autonomic flexibility. Oculomotor data revealed faster saccade velocities during video viewing in the OCD group; however, unlike controls, their eye movements did not correlate with the pleasantness of the content. Conclusions: These results support the theory that individuals with OCD may exhibit greater sympathetic activation and delayed parasympathetic engagement. The findings suggest that autonomic inflexibility may be a core, measurable feature of OCD.