Subsecond reward-related dopamine release in the mouse dorsal striatum.

Reward presentation is known to induce transient bursts of midbrain dopamine neurons in monkeys and rats, and the reward-induced dopamine overflow has been detected in the rat ventral striatum. To detect reward-related dopamine release in the dorsal striatum of behaving mice (C57BL/6), we used voltammetry with carbon-fiber microelectrodes implanted into the dorsal striatum. Dopamine signals increased transiently after food delivery with a peak at 0.6 s after the delivery onset. The success in detecting transient reward-response of dopamine in behaving mice opens a wide range of application to studies in mutant mice.