Auditory gating and its clinical correlates in adults with chronic tic disorder and neurotypical adults

Background: Over 80% of adults with chronic tic disorder (CTD) experience sensory over-responsivity (SOR), defined as heightened awareness of and/or behavioral reactivity to commonplace environmental stimuli. One potential mechanism underpinning SOR is sensory gating impairment. Sensory gating is the physiologic process whereby redundant stimuli are filtered out in early perceptual stages. In this study, we compared sensory gating between neurotypical and CTD adults and determined if gating indices associated with SOR. Methods: Neurotypical (n = 31) and CTD adults (n = 26) completed a clinical assessment, including two SOR measures (Sensory Gating Inventory, SGI; Sensory Perception Quotient, SPQ), and an auditory gating paradigm while monitored on EEG. Results: CTD adults exhibited greater SOR. Neurotypical and CTD adults did not differ in P50, N100, or P200 gating ratios. In regression analyses, N100 gating ratio was significantly associated with SGI score; the magnitude of this association was greater for neurotypical than CTD adults. No other significant associations emerged between gating ratios and SOR measures. Conclusion: Findings do not support sensory gating impairment as a mechanism underpinning SOR in CTD. The relationship between N100 gating and SOR warrants further investigation.