F values for significant main effects of longer duration of exposure on neurotransmitter concentrations, and duration by drug interactions that only showed significant effects of duration for one drug group (p < 0.05). Arrows indicate the direction of effects of duration compared to the AO group. Cells containing group names (α-PVP or Saline) indicate interactions that were only significant for one group. Cells without group names indicate main effects that occurred when data were collapsed across drug and saline groups. Degrees of freedom are 1, 28 for all comparisons except for 5-HIAA in PFC which has 1, 27 degrees of freedom.