Figure 3.

Short-access meth rats respond equally for novel and meth-conditioned cues in a relapse setting, but long-access meth rats respond preferentially for meth cues. (a) Long-access (LA) meth self-administration results in higher amounts of meth intake (and escalation) compared with short-access (SA) meth. *p<0.05 compared with the first long-access session. (b) Layout of the test chamber for Experiment 2. (c) Total lever presses over the 1-h novel cue relapse test from Experiment 2. *p<0.05, **p<0.01 compared with inactive responding within access condition. ++p<0.01 compared with active responding within access condition. (d) Relapse index reflects within-subject choice between meth-cue vs novel-cue (see Materials and Methods for formula). *p<0.05, **p<0.01 compared with SA group. ++p<0.01 compared with hypothetical mean of 0.50.