Figure 6. Ensemble encoding is task-specific.

Top plot shows ACC trajectories of population activity in low-dimensional space for several trials in one session, including three trials with off-task behavior (identified by trial numbers). In these cases, the animal approached the barrier, then backtracked from the barrier to the start feeder before returning to commit the climb and reach the target feeder. The running paths and velocity vectors are shown in the lower panels. Note that the neural trajectories deviate largely when the animal is on the second approach and climb (dashed lines in upper panel) as compared to trials with no off-task behavior (solid red-green-orange sequence of lines). This deviation occurs, even though the paths and velocity of the initial approach (fuchsia) and re-approach (black) are similar. This suggests that ACC is sensitive to past events – in this case, off-task behavior.