Author(s): ZOU, Z., XU, Y.W., CHAN, Q.H., Institution: GUANGZHOU SPORT UNIVERSITY, Country: CHINA, Abstract-ID: 231

Objective: Peripheral nerve injury (PNI) results in sensory deficits that trigger cross-modal compensatory mechanisms. This process induces cortical reorganization, which potentially modulates motor preparation and execution. However, how post-PNI neural plasticity influences multisensory integration—specifically audiovisual integration—and its subsequent effect on motor function remains poorly understood. This study investigates alterations in audiovisual integration in PNI patients and their impact on motor performance to provide a theoretical foundation for targeted rehabilitation protocols.
Methods: Upper-limb PNI patients, non-neural upper-limb injury patients, and age- and sex-matched healthy controls were recruited. Participants performed an audiovisual discrimination task during an electroencephalography (EEG) recording. The paradigm included three conditions: (1) Visual: discriminating arrow directions; (2) Auditory: responding to sounds from four spatial locations; and (3) Audiovisual: concurrent spatially congruent visual and auditory cues. Analysis focused on cognitive event-related potentials (P1, N1, N2) and motor-related potentials, specifically stimulus-locked lateralized readiness potential (s-LRP) for motor preparation and response-locked LRP (r-LRP) for motor execution.
Results: Unlike the control groups, PNI patients showed no significant differences in reaction time or accuracy between visual and audiovisual conditions, indicating impaired multisensory integration. EEG data revealed that PNI patients exhibited larger N1 amplitudes in the right parietal region during the auditory condition compared to the audiovisual condition, suggesting attentional deficits and diminished spatial discrimination. Regarding motor components, s-LRP and r-LRP amplitudes in PNI patients were significantly higher in the auditory condition than in visual or audiovisual conditions. This implies increased neural effort for auditory-triggered motor preparation and heightened difficulty in activating motor cortical areas.
Conclusion: PNI patients exhibit deficient audiovisual integration characterized by reduced attentional allocation and inefficient motor preparation for auditory cues. These findings suggest that rehabilitation strategies should prioritize visual cues to facilitate motor activation and address underlying attentional deficits. This study underscores the importance of incorporating multisensory integration assessments into clinical motor rehabilitation frameworks for PNI.