Figure 2.

Voxel selection. Top row: Voxels with coherence > 0.30 during localizer scan are shown in color overlay. Gray-scale images are motion- and distortion-compensated EPI data from successive slices in the Trio scanner (left and right images) and, Skyra (middle image). Bottom row: Each active voxel in V1 is marked, with color indicating to which quintile it belonged after event-related data were assessed for mean-normalized variance. Voxels in the top quintile (yellow, 80–100%) were discarded before the main analysis to minimize contamination by sagittal sinus and poor CNR due to edge effects.