Should I "stay" or should I "go"? Influence of an anticipated stop on cortical correlates of overground walking.

Real-world walking frequently requires pedestrians to maintain proactive inhibition to safely navigate unpredictable environments. While cortical modulations occurring during locomotion under environmental uncertainty are well-established, the specific proactive mechanisms underlying this state of inhibitory anticipation remain unexplored. This study aimed to investigate the behavioral and cortical shifts associated with anticipating a stop during overground walking. Fourteen healthy young adults performed fluent and cautious walking tasks with an expected stop. Cortical activity and trunk acceleration were recorded using a 32-channel mobile electroencephalography and an integrated accelerometer. Step-1 latency and step-interval variability were calculated via heel strike detection. Gait-phase-related power modulations were computed, and spectral principal component analysis was applied to attenuate artifacts. The results revealed that cautious walking significantly increased step-interval variability, whereas step-1 latency remained unaffected. At the cortical level, left frontotemporal areas exhibited an attenuated and delayed theta desynchronization during the swing phase. Furthermore, centroparietal regions demonstrated an altered temporal profile of alpha and beta synchronization, characterized by enhanced late-stance synchronization and reduced swing-phase synchronization. The present findings suggest that anticipating a potential stop may alter the rhythmic consistency of gait and reorganize phase-specific cortical dynamics. Being prepared to stop may shift the neural control of automated locomotion toward active monitoring, highlighting the relevance of proactive inhibition during everyday mobility.