Averaged traces of locomotor activity from 30-min-long recordings of mice receiving saline (upper row) and cocaine i.p. injections (lower row). N saline = 9; N cocaine = 8; N water = 11; N sugar = 6, where N is the number of mice. Statistical significance was evaluated by ANOVA repeated measurements in (A) and (C) for saline vs. cocaine and water vs. sugar, where****p < 0.0001. Statistical significance for (B) and (D) was evaluated by one-way ANOVA with Šidák multiple comparison, where water vs. sugar 1 day < 0.0001; water vs. sugar 7 days = 0.4835; sugar 1 day vs. sugar 7 days = 0.001; saline vs. cocaine 1 day = 0.1173; saline vs. cocaine 7 days = 0.0006; cocaine 1 day vs. cocaine 7 days = 0.095.**p < 0.01,***p < 0.001. H1 and H2, days of habituation to a cage, not included in the statistical analysis. The data are shown as mean ± SEM.
