Opioid regulation of reward in healthy humans


In our first opioid psychopharmacology study, we gave healthy young men pills containing 10 mg morphine to stimulate the µ-opioid receptor; 50 mg naltrexone to block µ- and kappa opioid receptors, and placebo (cherry flavoured breath mints) on three separate days.
As described more fully in the ensuing manuscripts, the data was consistent with the hypothesis that in the healthy human brain, endogenous opioids modulate the reward value and approach motivation of:
- Beautiful faces (pdf)
- Calorie-rich foods (pdf)
- Winning money (pdf)
- Social exploration of faces (pdf)
- But not caress-like touch (preprint)
