1. Rapid Serial Visual Presentation (RSVP) Task (abbreviated sequence) Simulates saccadic vision Used to gauge speed of visual object recognition Thorpe et al. (1996), Keysers et al. (2001), Johnson & Olshausen (2003) Barrage style visual oddball (low probability of target image) Use as a high vigilance stimulus for studying the neural origins of subjects’ response time variability. Fixation (2 seconds) Target RSVP Sequence (100 ms / image)

2. Single-trial discrimination Trials Stimulus locked time (ms) AzAz 0.51p = 0.01 250 ms 0.75 Trials Stimulus locked time (ms) AzAz 0.51p = 0.01 Trials Response locked time (ms) AzAz 0.51p = 0.01 Trials Response locked time (ms) AzAz 0.51p = 0.01 -200 ms Discrimination performance

3. Quantifying response locking Simulated EEG

4. Single-trial results Neural activity becomes strongly response locked during transition from far-frontal to parietal activity vs. 0-200-400-600-800-1000200 Response locked time (ms) AzAz RL% p = 0.01