Fig. 1: Mean distribution of brain glucose uptake, μ-opioid receptor availability and CB1 receptor availability in the whole study sample.

Top: Mean brain glucose uptake (BGU) of the 38 [18F]FDG scans (19 low-risk and 19 high-risk subjects). Middle: Mean binding potential (BPND) of the 41 [11C]carfentanil scans (22 low-risk and 19 high-risk subjects). Bottom: Mean volume of distribution (VT) of the 36 [18F]FMPEP-d2 scans (20 low-risk and 16 high-risk subjects).