The time-course of real-world scene perception: Spatial and semantic processing

Matt D Anderson; James H Elder; Erich W Graf; Wendy J Adams

doi:10.1016/j.isci.2022.105633

The time-course of real-world scene perception: Spatial and semantic processing

iScience. 2022 Nov 19;25(12):105633. doi: 10.1016/j.isci.2022.105633. eCollection 2022 Dec 22.

Authors

Matt D Anderson¹, James H Elder², Erich W Graf¹, Wendy J Adams¹

Affiliations

¹ Centre for Perception and Cognition, Psychology, University of Southampton, Southampton, UK.
² Centre for Vision Research, Department of Psychology, Department of Electrical Engineering and Computer Science, York University, Toronto, Canada.

Abstract

Real-world scene perception unfolds remarkably quickly, yet the underlying visual processes are poorly understood. Space-centered theory maintains that a scene's spatial structure (e.g., openness, mean depth) can be rapidly recovered from low-level image statistics. In turn, the statistical relationship between a scene's spatial properties and semantic content allows for semantic identity to be inferred from its layout. We tested this theory by investigating (1) the temporal dynamics of spatial and semantic perception in real-world scenes, and (2) dependencies between spatial and semantic judgments. Participants viewed backward-masked images for 13.3 to 106.7 ms, and identified the semantic (e.g., beach, road) or spatial structure (e.g., open, closed-off) category. We found no temporal precedence of spatial discrimination relative to semantic discrimination. Computational analyses further suggest that, instead of using spatial layout to infer semantic categories, humans exploit semantic information to discriminate spatial structure categories. These findings challenge traditional 'bottom-up' views of scene perception.

Keywords: Biological sciences; Neuroscience; Sensory neuroscience.