Feature-specific salience maps in human cortex

Abstract

Priority maps are representations of visual space that determine the relative importance of scene locations. Computational theories suggest that priority maps identify salient locations based on individual feature dimensions (e.g., color, motion), which are integrated into an aggregate priority map. While widely accepted, a core assumption of this framework--the existence of independent feature dimension maps in visual cortex--remains untested. Here, we tested the hypothesis that feature-selective retinotopic regions in human cortex act as neural feature dimension maps, indexing salience based on their preferred feature. We used fMRI activation patterns to reconstruct spatial maps while participants viewed stimuli with salient regions defined by color or motion direction. Reconstructed spatial maps selectively represented salient locations defined by each regions preferred feature. These findings identify spatially organized feature dimension maps that characterize the salience of scene locations based on a specific visual feature, confirming a key prediction of priority map theory.