Multimodal sensorimotor investigation of audio-visual integration in cochlear implant users

Rhythm is an omnipresent element of many daily activities. Numerous studies in cognitive sciences have highlighted that humans exhibit greater precision in synchronizing their movements with auditory rhythmic stimuli compared to visual ones. Deaf individuals were shown to excel in synchronizing with visual cues, surpassing those with normal hearing (NH). Furthermore, it was demonstrated that cochlear implant (CI) users were able to move in time to the beat of music, although not as well as NH controls. This study aims to investigate whether CI users retain a visual synchronization advantage from their pre-implant deafness, while maintaining auditory synchronization skills comparable to those of NH individuals, or if the neural reorganization post-implantation negates the visual synchronization advantage acquired pre-implantation. Specifically, we assessed both unimodal and multimodal auditory and visual abilities in CI users compared to NH controls using a standard sensorimotor synchronization paradigm. Results revealed that CI users exhibit comparable auditory rhythmic synchronization abilities to NH individuals, which is consistent with existing research, while not displaying a superior ability in synchronizing with visual rhythms, likely due to neural reorganization following implantation. This shift in audio-visual integration among CI users suggests that the post-implant reorganization of their auditory cortex might hinder the effective integration of temporal auditory input from the implant with visual information.