Feasibility of Vibrotactile P50 Sensory-Gating Assessment Using Portable EEG

Sensory gating (SG), most commonly quantified using the auditory P50 event-related potential elicited by a paired "double-click" paradigm, is a well-established biomarker of early sensory inhibition that reflects the brain's ability to suppress responses to repetitive sensory input. Although auditory SG paradigms have been widely used in both research and clinical settings, they impose an unavoidable auditory load and are generally limited to controlled laboratory environments, reducing their suitability for ecological monitoring and applications in which auditory resources must remain available. This study evaluated the feasibility of a portable vibrotactile sensory-gating system designed to assess inhibitory processing without engaging the auditory or visual modalities. Fifteen healthy adult participants completed both auditory and vibrotactile paired-stimulus conditions using a within-subject experimental design. Vibrotactile stimuli were delivered through transducers positioned on the volar surface of the forearm while electroencephalographic (EEG) activity was recorded using a 32-channel Emotiv EPOC Flex system. Event-related responses were extracted and analyzed using conventional sensory-gating metrics to enable direct comparison between modalities. Vibrotactile stimulation elicited time-locked P50 responses with attenuation of S2 relative to S1. Mean S2/S1 ratios were 0.521 +- 0.041 for the auditory condition and 0.524 +- 0.064 for the vibrotactile condition. The paired difference was 0.0029 (95% CI, −0.0221 to 0.0279), t(14) = 0.249, p = 0.807, dz = 0.064. No statistically significant difference was detected between modalities in this sample. These group-level findings support further evaluation of portable vibrotactile P50 measurement.