As noted above, to ensure that cell recordings were made at dopamine-rich regions of the NAc, prior to the start of each session electrical stimulation was applied to the VTA and stimulated dopamine release was measured. Interestingly, the average concentration of stimulated dopamine was approximately double at phasic locations compared to NP locations. For the core, stimulated dopamine release in phasic locations was 1270 ± 320 nM vs NP locations; 590 ± 130 nM (t29 = 2.10, p < 0.01). Likewise, for the shell stimulated dopamine release at phasic locations was 650 ± 260 nM vs 280 ± 40 nM at NP locations (t31 = 2.29, p < 0.05). Furthermore, examination of [DA] changes following electrical stimulation prior to each experiment revealed differences in dopamine reuptake between core and shell locations. Specifically, calculation of dopamine half-life (when DA concentration is half of total stimulated release) revealed significant differences between the core (1315 ± 85 ms) and shell (1546 ± 75 ms) (t73 = 2.06, p < 0.05). Importantly, the differences in stimulated dopamine release peak concentrations and reuptake values across
