Figure 1.

Maze diagram and schematic of the trials. The rats were trained on a T-maze task in which the reward locations (small circles) were indicated by flashing lights near the rewards (a left-rewarded example is indicated). The schematic timeline indicates key task events, including the trial start, light onset, arrival at the choice point and the reward. After a ~30 sec ITI, the rats were placed on the maze facing away from the choice point (Trial Start). One of the cue lights was illuminated ~3 sec later when the rat started down the stem of the maze (dashed line on the T-maze diagram). The light remained illuminated throughout the trial, until after the rat consumed the reward. Approximately 1.5 sec after light onset, the rats reached the choice point and after another ~1.5 sec the rat reached the reward location. Each of these times varied somewhat from one rat to another and across trials. Analysis of event-related firing of individual neurons compared firing during the 1 sec before and after the event (grey shaded regions).