Fig. 2: fMRI task design and measurements.
From: Perception and memory have distinct spatial tuning properties in human visual cortex
a Following training, participants participated in two tasks while being scanned. During perception runs, participants viewed the colored fixation dot cues and associated stimuli while maintaining central fixation. Participants performed a one-back task on the stimuli to encourage covert attention to each stimulus. During memory runs, participants viewed only the cues and recalled the associated stimuli while maintaining central fixation. Participants made a judgment about the vividness of their memory (vivid, weak, no memory) on each trial. We used the perception and memory fMRI time series to perform a GLM analysis that estimated the response evoked by perceiving and remembering each stimulus for each vertex on the cortical surface. Responses in visual cortex for an example participant and stimulus are shown at bottom. b In a separate fMRI session on a different day, participants participated in a retinotopic mapping session. During retinotopy runs, participants viewed bar apertures embedded with faces, scenes, and objects drifting across the visual field while they maintained central fixation. Participants performed a color change detection task on the fixation dot. We used the retinotopy fMRI time series to solve a pRF model that estimated the receptive field parameters for each vertex on the cortical surface. A polar angle map is plotted for an example participant at bottom.
