Fig. 4.

Elevated plus maze test during withdrawal in alcohol vapor-escalated vs. non-escalated and naive rats. a Percent time spent on the open arms. b Number of open arms entries. c Number of total arm entries. The data indicate higher anxiety-like behavior in rats that escalated alcohol vapor self-administration. d Development of mechanical hypersensitivity after 24 sessions of alcohol vapor self-administration. The data are expressed as mean ± SEM. **p < 0.01, vs. naive rats; ^#p < 0.05, ^##p < 0.01, vs. non-escalated rats