Early visual perceptual processing is altered in obsessive–compulsive disorder

Abstract

ObjectiveExisting studies have shown changes in attention and emotion processing of disorder-relevant visual stimuli in those with obsessive compulsive disorder (OCD). However, early visual processing in OCD has not been assessed, as previous studies did not examine the entire time course of visual processing but instead assessed potential differences in pre-determined visual evoked potentials (VEPs). This study investigates the entire visual processing stream in OCD compared to healthy age-matched controls (HC) using emotionally-neutral visual stimuli and a data-driven rather than hypothesis-driven approach. Methods35 HC and 26 participants with OCD underwent EEG recording while completing a modified Eriksen flanker task. Permutation-controlled t-tests were used to identify group differences in the data’s full time course of visual evoked potentials. Baseline-corrected amplitudes at time points where the groups were significantly different were analyzed using ANCOVAs with BDI, BAI, and SNAP-inattentiveness scores included as covariates. ResultsThis analysis identified enhanced P1 amplitudes to two visual stimuli (the initial flanker and the stimulus), corresponding to time windows of 65–93 ms and 157–187 ms post-flanker presentation in the OCD group compared to controls. Group (OCD vs. HC) was the strongest predictor of VEP amplitude during both time windows, with no significant influences of any covariates. ConclusionsThis study showed an enhanced P1 component in people with OCD to neutral visual stimuli, potentially reflecting either inefficient or excessive early visual processing in this population. Additional inquiry is necessary to determine whether altered visual processing is associated with the sensory hypervigilance observed in those with OCD. SignificanceThis work identifies early visual processing alterations in OCD using neutral stimuli and a data-driven approach.