||Little existing research has assessed the potential role of the nucleus accumbens (NAc) in interval timing processes (i.e., timing in the seconds to minutes range). Based on research suggesting that NAc dopamine (DA) levels reflect incentive, as well as research indicating that perceived incentive alters time perception, we employed a dopaminergic modulation technique in order to test the hypothesis that the NAc modulates clock speed based on incentive. Rats were trained on either a 10-second or a 30-second peak-interval (PI) procedure and received intra-NAc microinfusions of sulpiride, amphetamine and saline. Results showed that NAc DA modulations had no effect on timing, but intra-NAc sulpiride microinfusions significantly decreased rats' probability of responding, and rats' peak response rates on trials in which they responded, relative to saline and amphetamine. Our findings therefore suggest that neither NAc dopamine levels, nor the resultant changes in incentive computed by this structure, impact temporal control.