Motivation for reward as a function of required effort:Dissociating the 'liking' from the 'wanting' systemin humans

摘要

Recent studies investigating the neurobiology ofreward motivation in animals have begun to deconstructreward into separable neural systems involving the 'liking'of a reward (hedonic enjoyment of consumption) versus the`wanting' of a reward (incentive salience to obtain reward).To date, however, it is unclear whether these systems arealso separable in humans. We examined this question bymanipulating the effort (clicking on a moving square)required for participants to obtain a reward (humorous ver-sus non-humorous cartoon). Overall, as the required effort toview a humorous cartoon increased, participants were lesslikely to choose this reward. Moreover, individual differ-ences in cartoon preference predicted cartoon choice at lowlevels of required effort, but not at high levels of requiredeffort. These findings suggest that manipulating effort maybe a valid method for dissociating the 'liking' from 'want-ing' components of reward motivation in humans.