Data were analyzed with either two- or three-way ANOVA with repeated measures when applicable, followed by either post hoc Bonferroni test (more than two groups) or by independent samples unpaired t-test (two groups). Correlations between locomotor activity and place preference during the place preference test were calculated using Pearson's correlation. Statistical analyses were performed by using the statistical software packages SPSS 15.0 for Windows (SPSS, Chicago, IL, USA) and the Prism 5.0 program (GraphPad Software). Statistical significance was set at p<0.05. Data from both sexes were pooled unless otherwise stated. Data are expressed as means ± standard errors of the mean (SEM).
