Figure 3. A cue paired with either rapid or slower cocaine injections acquires similar conditioned rewarding properties, and these properties abate with time.

Presses on the CR and NCR levers on Day 1 (panel A), Days 10–11 (panel B) and Day 30 (panel C) of withdrawal from self-administered cocaine in the 5- and 90-s groups. Values are mean ± SEM. n's = 5/group. s, seconds; CR, conditioned reward lever; NCR, non-conditioned reward lever. *p<0.05 compared with NCR within the same group.