Distinct roles of central and peripheral vision in rapid scene understanding.

Central and peripheral vision loss, caused by conditions such as age-related macular degeneration and retinitis pigmentosa, disrupt visual processing in distinct ways, yet their impact on real-world scene perception remains poorly understood. Here, we used a real-time, gaze-contingent simulation to examine how central vision loss and peripheral vision loss alter eye movements and scene understanding. Sighted participants (n = 32, five males) viewed 120 real-world scenes (50% social interaction, 50% neutral) under one- or three-saccade constraints and described each scene; description quality was quantified via semantic similarity to ground-truth responses. Peripheral vision loss observers produced significantly less informative descriptions than both central vision loss and control participants, particularly for social interaction scenes, suggesting that peripheral vision is critical for rapid extraction of scene semantics. In contrast, central vision loss primarily disrupted oculomotor behavior, including increased saccade amplitudes, delayed saccade initiation, and reduced intersubject fixation consistency. Description quality was not predicted by fixation similarity to controls but by fixations to labeled humans and critical objects, underscoring the role of semantically informative sampling for real-world scenes that include people. These results reveal a dissociation between perceptual and oculomotor consequences of vision loss and highlight the importance of peripheral input for real-world scene understanding.