Figure 1.
(A) Sequence of events in the delayed-response task. Rats pressed a lever for 1000 ms (delay period) and released the lever within 600 ms of the onset of an auditory trigger stimulus (Correct responses) presented at the end of the delay period. Two types of errors occurred in the task. Premature errors occurred if the lever was released before the trigger stimulus. Late errors occurred if the reaction time was greater than 600 ms.