Abstract
In everyday vision, we experience an >180 degree view of the world in front of us. However, traditional functional magnetic resonance imaging (fMRI) setups are limited to presenting scenes like postcards in the central 10-15 degrees of the visual field. Here, we develop a method for ultra-wide angle visual presentation in the scanner, and explore how the brain processes visual scene information when presented with immersive first-person views. To accomplish wide-angle projection, we bounced the image off two angled mirrors directly into the scanner bore onto a custom-built curved screen, creating an unobstructed visual presentation of over 175 degrees. Additionally, we presented images that depicted a compatible wide field-of-view, rendered from 3D scenes built in Unity software; using standard scene images led to distorted perceptions of the environment. With this setup, we measured brain responses to a range of stimuli, including scene images presented in the full-field and at a typical smaller visual size. We found that all classic scene areas (parahippocampal place area, retrosplenial cortex, and occipital place area) were activated significantly more to the full-field scenes compared to the postcard scenes, indicating their preference for the far-periphery. Crucially, we found that a large swath of cortex connecting these areas was also strongly activated by the full-field more than the postcard scenes, forming a ring-shape around the parieto-occipital sulcus. Theoretically, these findings raise an intriguing possibility that there are representational principles unifying what are currently considered separate scene-selective regions within a common large-scale organization. Methodologically, our approach provides a novel avenue to test hypotheses relating to the foveal-peripheral organization of higher-level visual areas, and measure scene processing mechanisms with an immersive experience of scale.