Figure 1.
(A) Schematic of change detection task showing two clip-art trials (figure not drawn to scale). Rhesus monkeys viewed sample displays for 5 s, followed by 50-ms delays. Monkeys were reinforced with either cherry koolaid or a 300-mg banana pellet (pseudorandomly) following correct responses. Trials were separated by 15 s (intertrial interval) accompanied by dim green light through a slit between the monitor and chamber. Green-light offset cued the start of the next trial. Humans viewed sample displays for 1 s, followed by 900-ms (colors) or 1000-ms (clip art) delays, with 2-s intertrial intervals. Dim room illumination red (incorrect) and green (correct) lights behind humans provided feedback; light offset cued the start of the next trial. (See supplement for more details and rationale.) (B) Change detection percent-correct performance by monkeys and humans. Error bars represent standard error of the mean.