Dissociable cortical contributions to impulse control during waiting

Self-control requires regulating actions over time, particularly suppressing impulsive actions to obtain future rewards. Using a delayed-response task in mice, we identified distinct cortical contributions to impulse control during waiting. Optogenetic inhibition revealed that the dorsomedial frontal cortex (dmFC) promotes patience, the anterior insular cortex (AIC) drives impulsivity, and the posterior parietal cortex (PPC) regulates temporal precision in waiting. Calcium imaging uncovered region-specific computations: PPC neurons predominantly encoded absolute elapsed time through time cell-like activity, tiling the waiting period independently of patience levels. Their activity predicted the waiting precision. Meanwhile, dmFC and AIC neurons exhibited opposing lick-related activity-dmFC neurons preferentially decreasing and AIC neurons increasing activity during licking. Furthermore, their activity changes during waiting predicted patience. These findings reveal distinct yet complementary mechanisms underlying impulse control during waiting: The PPC encodes temporal information crucial for regulating waiting behavior, while the dmFC-AIC circuit orchestrates a push-pull dynamic to regulate patience.