Vibrotactile beat sensitivity in deaf individuals: behavioral and neural evidence.

Beat sensitivity is typically studied in the auditory modality, yet the temporal prediction mechanisms that support beat processing are thought to be supramodal and may be accessible through other sensory channels. Deafness provides a powerful model for examining whether these mechanisms can be recruited through somatosensory input. We compared vibrotactile beat sensitivity in deaf (n = 17) and hearing (n = 16) adults using frequency-tagging EEG and sensorimotor synchronization (SMS) during exposure to isochronous and temporally complex vibrotactile rhythms. Neural entrainment was quantified as spectral power at beat-related frequencies, while SMS variability indexed behavioral precision. Deaf participants exhibited significantly stronger neural entrainment to vibrotactile rhythms than hearing controls. Behaviorally, deaf individuals showed reduced tapping variability, an effect that was selectively enhanced for temporally complex rhythms, suggesting more efficient extraction of higher-order temporal structure. These neural and behavioral enhancements occurred despite comparable within-group entrainment across rhythm types. Together, these findings demonstrate that beat-based temporal prediction can be robustly achieved through vibrotactile input in the absence of auditory experience. This work provides combined behavioral and neural evidence for vibrotactile beat sensitivity in deaf individuals and indicates that somatosensory pathways can support predictive timing mechanisms typically associated with audition.