Statistical analyses
Univariate ANOVAs with the main factor group (PK, LK, PP) were performed for the psychometric measures and the acute rCBF data. The data from the left and right hemispheres was averaged for each ROI. To correct for multiple testing, a Bonferroni adjusted alpha level of α = 0.0167 (α = 0.05/3) was applied to the analysis of the three ROIs of main interest. In case of a significant main effect of group, Tukey’s post hoc tests were performed, and for the rCBF data the following additional analyses were conducted: 1. To investigate prolonged effects, a univariate ANOVA at the delayed time point was conducted. 2. To investigate effects of laterality, univariate ANOVAs for left and right ROIs were conducted separately. 3. To investigate differences between the two time points within groups, paired 