The nucleus accumbens (NAc) is thought to integrate information that is conveyed by (1) dopaminergic inputs from the midbrain and (2) glutamatergic inputs from limbic and cortical regions,including the amygdala,prefrontal cortex (PFC),hippocampus,and thalamus [1],and signal to the basal ganglia motor system to guide appropriate behaviors.Addictive drug use is proposed to hijack this system,enhancing the brain\'s reactivity to drug cues and triggering drug-seeking and relapse after prolonged withdrawal [2,3].Both positive reinforcement (rewarding effects of drugs) and negative reinforcement (aversive emotional state associated with withdrawal) have been considered to play critical roles in the etiology and maintenance of drug addiction,and NAc neurons are capable of processing both reward and aversion [4,5].