Figure 1.

Checkerboard and scene pRF mapping stimuli and task schematics. A, Example frames during checkerboard pRF mapping runs. A 100% contrast flickering (6 Hz) circular (21° diameter 7T; 10.5° diameter 3T) checkerboard stimulus was presented through a bar aperture that moved gradually through the visual field. A single sweep across the visual field took 36 s and consisted of 18 equal time (2 s) and width instances of the aperture. In each run, the aperture completed eight sweeps (2 orientations, 4 directions). Participants were required to maintain fixation and indicate the detection of a color change at fixation, via a button press. B, Example frames from scene pRF mapping sessions. The aperture, its progression across the visual field, and the detection task were identical to that used during checkerboard pRF runs. Scene images of identical dimensions replaced the checkerboard stimulus with images changing every 400 ms (5 per aperture position). Over an entire sweep, 90 scene images (5 × 18 aperture positions) were presented at random without replacement, guaranteeing that no scene was presented twice within a sweep.