Figure 2. In Experiment 1, there were no differences in the amount of cocaine exposure, cocaine-cue exposure, or number of days to reach each infusion criterion between the 5- and 90-s groups.

Total drug intake (panel A), number of cue-cocaine pairings (panel B) and days to reach infusion criteria (panel C). Note that total drug intake includes cocaine taken during self-administration training, when all rats self-administered cocaine injections delivered over 5 seconds. Rats were required to meet infusion criteria 10–25 for 2 days each and infusion criterion 30 for 5 days. Values are mean ± SEM. n's = 5/group. s, seconds. CS, conditioned stimulus; UCS; unconditioned stimulus.