2A) reached a similar number of infusions by the third hour, regardless of treatment. Repeated measures ANOVAs on BPs, which included only the initial BPs for all animals (including those for which sessions were restarted) showed a significant main effect of treatment [F (2, 22) = 4.13, p = 0.030] on the test day, but not on baseline days (Fig 2B). Bonferroni corrected pairwise mean comparisons detected no significant difference among treatments on the test day, however a strong statistical trend was observed between aCSF and OxoSQ 10 nmol (p = 0.061). The number of cocaine infusions during any of the time bins between baseline sessions and aCSF sessions did not differ appreciably (Fig 2A inset). Similarly, the number of cocaine infusions during any of the time bins between aCSF and CIC microinjection with OxoSQ 10 nmol did not differ significantly (Fig 4A). The ratio of the inactive/active lever presses on average was small at 0.012 ± 0.0016 (Mean ± SE), indicating low levels of inactive lever pressing, and there were no appreciable differences between any of the treatments or baseline sessions with regard to this ratio. This indicates that animals primarily associated the active lever with cocaine infusion rewards.
