This is in line with the observation that opioids play an important role in reproduction, an effect mainly mediated by the hypothalamus and amygdala ( Kostarczyk, 1986 Le Merrer et al., 2009). However, in the rodent it has been shown that the ensuing pleasure of these goal directed behaviors that is the hedonic aspect of reward consumption is mediated by an additional, opioidergic system ( Peciña and Berridge, 2005). Goal directed behaviors such as finding a sexual mate or searching for food are crucial for survival and subserved by a mainly dopaminergic motivational system including the ventral striatum ( Morton et al., 2006). The Reviewing Editor's assessment is that all the issues have been addressed ( see decision letter). Crucially, the naloxone induced activation decrease was observed at reward delivery, but not during reward anticipation, indicating that blocking opioid receptors decreases the pleasure of rewards in humans.Įditorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. This was paralleled by a reduction of activation in the ventral striatum, lateral orbitofrontal cortex, amygdala, hypothalamus and medial prefrontal cortex. Our data show that blocking opioid receptors reduced pleasure associated with viewing erotic pictures more than viewing symbols of reward such as money. We investigated this issue using a within subject, pharmacological challenge design with the opioid receptor antagonist naloxone and fMRI. Importantly, enjoying the pleasure of a reward is distinct from incentive salience induced by cues predicting the reward. It has been hypothesized that the pleasure of a reward in humans is mediated by an opioidergic system involving the hypothalamus, nucleus accumbens and the amygdala.

Hedonic