Allocentric and egocentric cues constitute an internal reference frame for real-world visual search

Visual search in natural environments involves numerous objects, each composed of countless features. Despite this complexity, our brain efficiently locates targets. Here, we propose that an internal reference frame facilitates real-world visual search. Objects in natural scenes often appear in orientations perceived as upright, enabling quicker recognition. However, how object orientation influences real-world visual search remains unclear. Moreover, the contributions of multiple reference cues—egocentric, visual context, and gravitational—on visual search are not well understood. To answer these questions, we designed a visual search task in virtual reality. Our results revealed an orientation effect that was independent of set size, suggesting the involvement of internal reference frame transformation. By independently rotating the virtual scene and participants in a flight simulator, we found that allocentric cues significantly altered search performance. These findings provide fundamental insights into the efficiency of real-world visual search and its connection to high-level cognitive processes.