Architecture shapes event boundaries: Theta dynamics of event segmentation during spatial transitions

Human experience unfolds continuously, yet it is remembered and understood as a sequence of discrete events. How the brain segments this stream of experience, particularly under naturalistic conditions, remains poorly understood. Here we investigate the neural dynamics associated with event boundaries during active navigation through architectural transitions. Using mobile electroencephalography combined with virtual reality, we analyzed data from participants freely walking between rooms and repeatedly crossing doorways. Time-frequency analysis of source-localized neural activity revealed a robust increase in theta-band power (4-8 Hz) over temporo-occipital and parietal regions approximately 300-450 ms after passing through a doorway. This effect was consistent across participants and independent component clusters, indicating a reliable neural signature of architectural transitions. We interpret this theta response within frameworks of event segmentation and Bayesian inference, suggesting that doorways trigger a transient reconfiguration of distributed neural networks when ongoing predictions can no longer be maintained and a new event model must be inferred. By preserving the natural coupling between perception, movement, and environmental structure, our findings demonstrate that architecture provides meaningful boundaries that shape brain dynamics and the organization of experience. More broadly, this work highlights the power of naturalistic experimentation and positions architectural space as an active medium for investigating how the brain structures events.