Endorphin release is significantly greater in the right NAc (A: t = 3.25, p = 0.009) and significantly lower in the left mOFC (B: t = 2.34, p = 0.041) and right mOFC (C: t = 2.60, p = 0.027) of individuals with the val/val genotype. Blue circles indicate control subjects, red circles indicate heavy social drinkers.
Reproduced with permission from [61] under the terms of the Creative Commons Attribution License (CC BY) https://creativecommons.org/licenses/by/4.0/
COMT: Catechol-O-methyltransferase; mOFC: Medial orbito-frontal cortex; NAc: Nucleus accumbens.