Fig. 3.

Arc/Arg 3.1 KO mice show early impairments in cocaine IVSA acquisition but normal extinction.

Average nose-pokes (active, large boxes; inactive, small boxes) for WT versus Arc/Arg3.1 KO mice, during the first 7 days of (A) acquisition (1.0 mg/kg/inf, cocaine) and (D) extinction (saline with cue light) (n = 8 WT, 10 KO). Time out responses are excluded. For acquisition, active nose-pokes equal reinforcers earned. As animals met criteria, they were moved to the next phase. Percent of animals remaining in each group over (B) acquisition and (E) extinction sessions were not different. Statistical comparisons of active and inactive nose-pokes were made between groups using each animal’s first and last sessions for (C) acquisition and (F) extinction. *p < .05; except for (B,E), data shown are mean ± S.E.M.