(A) A previous study (Vo et al, 2017) compared voxel receptive fields (vRFs) between different attention conditions (yellow dashed circle). vRFs were mapped with flickering checkerboard stimuli (depicted as white circles) presented at different locations on different trials. fMRI responses to these stimuli can be used to compute vRFs for each condition (right; white dashed circle; example voxel shown), demonstrating effects of attention on vRF position. (B) I propose to manipulate several stimulus properties: contrast (bright vs dim), size (small vs large), and the number of stimuli (single stimulus vs. several). (C) Within these stimulus manipulations, I will also manipulate the location of attention: participants will attend to fixed locations on the screen (as in A), or one or more visual stimuli presented. In all experiments gaze will be fixed.
This project seeks to develop new understanding for how brain networks support dynamic neural representations that are the cornerstone of cognition. The expectation is that a new understanding of these processes can be used to identify avenues for intervention to improve human perceptual and cognitive performance in demanding environments.