Theta activity supports landmark-based correction of naturalistic human path integration

How do humans integrate landmarks to update their spatial position during active navigation task? Using immersive virtual reality and high-density mobile EEG, we investigated the neural underpinnings of landmark-based recalibration during path integration. Our findings reveal that a briefly presented intramaze landmark effectively corrected accumulated homing errors. However, this effect was transient and less optimal when participants were highly confident in their self-motion-based spatial representation suggesting that internal priors hinder the assimilation of novel spatial cues. At the neural level, RSC theta-band activity supported these recalibration processes. When fine adjustments of the spatial representation were sufficient, landmark presentation elicited stronger theta-band activity and greater phase resetting compared to when substantial spatial updating was necessary. Our results also revealed motor-related theta activity that scaled with acceleration during rotational corrections, highlighting the dual role of theta in the flexible integration of multimodal signals, involved in both landmark-based spatial updating and self-motion encoding.