Sulpiride blocks the transient attenuation of vSub–NAc drive after tetanic stimulation. A, When displayed on a expanded time base, a significant transient decrease in fimbria-evoked spike probability is revealed immediately after tetanic stimulation and has a duration of ∼1 min (open circle) (n = 36). The arrow indicates the time at which tetanic stimulation and TTX infusion are applied to the fimbria and the mPFC, respectively. B, The transient decrease observed after the tetanic stimulation is blocked by previous systemic administration of sulpiride (5 mg/kg; open circle) (n = 17). The arrow indicates at which time tetanic stimulation is applied to the fimbria. Error bars indicate SEM. *p < 0.05.