Figure 1.
Tasks and conditions, experiment 1. A, Example trial for saccade task. While subjects maintained fixation on the white fixation dot, a memory cue appeared briefly at another location. Subjects were instructed to hold this cued location in memory throughout the trial. The fixation dot then moved, and after completion of a saccade to the new fixation location, a probe stimulus (oriented bar) appeared after a variable delay in either the spatiotopic (top), retinotopic (middle), or control (bottom) location of the cue. Subjects made a button press response to indicate probe orientation. A memory test stimulus then appeared, and subjects indicated whether it occupied the same spatiotopic location as the memory cue. B, In the no-saccade task, subjects remained fixated on the original location for an equivalent amount of time, so that probe delays relative to the cue were consistent across tasks. Probes appeared in the spatiotopic/retinotopic (top) or control (bottom) locations. C, In the return-saccade task, subjects held fixation at the second location for 750 ms before making a return saccade back to the first fixation location. Probes appeared at the spatiotopic/retinotopic (top), updated retinotopic (middle; reported in supplemental material, available at www.jneurosci.org as supplemental material), or control (bottom) locations; probe delays were the same as in the saccade task relative to onset of the final fixation. Gray arrows indicating saccades did not actually appear on screen. Stimulus configurations illustrated here represent only one of 108 possible cue–saccade configurations for each task (for additional examples, see supplemental Fig. 1, available at www.jneurosci.org as supplemental material).
