(A) Percentage of neurons with significant press, delay, and release activity among neuronal ensembles recorded from dmPFC. Example of single neurons modulated around (B) press, (C) delay, and (D) release. Rasters aligned to lever release. Gray regions indicate temporal epochs used to assess the statistical significance of event-related modulation of firing rate. In (B), modulation was assessed using rasters aligned to lever press. Rasters are sorted by lever press duration with long lever presses at the top.