Experimental paradigm and evoked responses.

<p><b>A:</b> The visual stimulus used in the experiment, where it is superposed on a gray background. The solid black circles and cross are always present, to aid fixation. The three dashed isoeccentric rings reverse 4 times per second, where the two patterns are shown at the bottom of this frame. <b>B:</b> Retinotopic mapping the allowed the locations of the 3 concentric rings to be independently identified, where the colors represent the measured eccentricity, colored from red at the fovea to blue at 6°, as shown in the circular inset, with magenta and gray at larger eccentricities <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1002435#pcbi.1002435-Schira1" target="_blank">[3]</a>. <b>C:</b> Spatiotemporal snapshots showing the response to first ring at various times after stimulus onset. The colors represent percentage signal change, as labeled on the colorbar.