Figure 1.

1, Task description. The experimental procedure is a cued-target detection based on a dual RSVP paradigm (Yantis et al., 2002; Ibos et al., 2009). The monkey is required to maintain its gaze on the central fixation point all throughout the trial. A first stream of stimuli, a succession of visual stimuli every 150 ms, is presented either within (as here) or opposite the fixation point from the cell's receptive field. Three hundred milliseconds later, a second stream appears opposite the first stream from the fixation point. Then, 300, 450, or 600 ms (here, 300 ms) after the second stream onset, a cue is presented within the first stream. This cue can be a green Stay cue, indicating to the monkey that the target has an 64% probability to appear within this very same stream, or a red Shift cue (as here), indicating that the target has a 64% probability to appear within the opposite stream. In 80% of the trials, the target is presented 150, 300, 600, or 900 ms from cue onset. In 80% of these target trials (64% of all trials), the target location is correctly predicted by the cue (valid target, as here). In 20% of these target trials (16% of all trials), the target location is incorrectly predicted by the cue (invalid target). In the remaining 20% of trials, no target is presented (catch trials) so as to discourage FAs. The target is composed of just one horizontal and one vertical spatial cycle, whereas distractor items are composed of up to six horizontal and vertical spatial cycles. The monkey gets rewarded for responding by a bar release between 150 and 750 ms after target presentation and for holding on to the bar when no target is presented. 2, 3, Cue validity effects. Both monkeys respond faster (2) and have higher DRs (3) on valid cue trials than on invalid cue trials (mean ± SE) in both the FEF (black) and LIP (gray) recording sessions. **p < 0.01; ***p < 0.001.