Walking Selectively Modulates Behaviorally Relevant Auditory Responses According to Stride Cycle Phase

Human perception operates in dynamic environments, requiring sensory processing to continuously adapt to ongoing motor activity. Here, we investigated how natural walking modulates auditory change detection by recording EEG while participants performed a transitional click train task during sitting and walking. Behaviorally, walking significantly elevated auditory change detection thresholds, reflecting reduced perceptual sensitivity. Electrophysiologically, three distinct auditory responses onset, change, and offset were evoked; both the onset and change responses were attenuated during walking, with the most pronounced effect observed for the cognitively demanding change response. Notably, this modulation was further amplified for the change response during active engagement compared to passive listening, implicating attentional resource allocation. Strikingly, both behavioral performance and change-related neural responses fluctuated rhythmically with the gait cycle, while onset and offset responses remained comparatively stable. Together, these findings reveal a stride-phase-dependent gating mechanism that selectively modulates perceptually relevant auditory signals, illustrating how the brain rhythmically reallocates sensory resources to optimize perception during locomotion.