Differential neural responses to rhythmic motion and rhythmic static auditory stimuli: An EEG and fNIRS study

Rhythmic auditory stimuli are widely used in neuromodulation, particularly in motor rehabilitation, due to their ability to facilitate auditory-motor entrainment. However, most research has primarily focused on the temporal properties of auditory stimuli, overlooking the potential influence of spatial motion information on neural processing and motor cortical activation. This study aimed to examine the neural effects of rhythmic motion auditory stimuli that couple auditory rhythmic information with spatial motion information. Specifically, differences in brain responses to rhythmic static and motion auditory stimuli were explored. Electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) were simultaneously recorded to measure neural oscillations and hemodynamic responses in the motor cortex. Participants were exposed to both rhythmic static and motion auditory stimuli, and their cortical activation patterns were analyzed. The results showed that both rhythmic static and rhythmic motion auditory stimuli elicited robust rhythmic neural responses. Compared with rhythmic static auditory stimuli, rhythmic motion auditory stimuli were associated with stronger neural modulation and more extensive activation patterns. These findings suggest that incorporating spatial motion information into rhythmic auditory stimulation may enhance auditory-motor coupling and recruit additional neural processes related to spatial motion perception and rhythm processing. Overall, the present study highlights the importance of considering spatial dynamics in the design of rhythmic auditory stimuli and provides new evidence for how temporal and spatial information jointly shape neural responses during rhythmic auditory processing. These insights may inform the development of more effective auditory-based neuromodulation and rehabilitation strategies.