Fig. 2.

Decoding stimulus orientation from ensemble fMRI activity in the visual cortex. (a) Decoded orientation responses for eight orientations. Polar plots indicate the distribution of predicted orientations for each of eight orientations (S2, 400 voxels from V1/V2, 22 samples per orientation). The same values are plotted at symmetrical directions as stimulus orientation repeats every 180°. Solid black lines show the true stimulus orientations. (b) Decoded orientation responses for all four subjects (400 voxels from V1/V2, total 160–192 samples for each subject). Results for individual orientations are pooled relative to the correct orientations, and aligned to the vertical line. (c) Across-session generalization. Decoded orientation responses were obtained by training a decoder with Day 1’s data and testing with Day 2’s data (31 days and 40 days apart for S1 and S2, respectively).