Attention Modulates Stimulus Representations in Neural Feature Dimension Maps

Computational theories posit that attention is guided by a combination of spatial maps for individual features that can be dynamically weighted according to task goals. Consistent with this framework, when a stimulus contains several features, attending to one or another feature results in stronger fMRI responses in regions preferring the attended feature. We hypothesized that multivariate activation patterns across feature-responsive cortical regions form spatial ‘feature dimension maps’, which combine to guide attentional priority. We tested this prediction by reconstructing neural feature dimension maps from fMRI activation patterns across retinotopic regions of visual cortex using a spatial inverted encoding model. Participants viewed a peripheral visual stimulus at a random location which always contained moving colored dots. On each trial, participants were precued to report the predominant direction of motion or color of the stimulus, or to attend fixation. Stimulus representations in reconstructed priority maps were selectively enhanced in color-selective regions when color was attended, and in motion-selective regions when motion was attended, and this effect was primarily observed at the stimulus location. While enhancement was localized to the stimulus in color-selective regions, motion-selective regions were globally enhanced when motion was task relevant. These results suggest different cortical regions support spatial maps of different visual features, and that each map is uniquely reweighted based on task demands to guide visual behavior towards the most relevant locations based on important features.