BEING FASTED REDUCES TOUCH REWARD

Hunger constitutes one of the strongest motivators in the animal kingdom with the potential to override almost all competing incentives. While short-term hunger is ubiquitous in our daily lives, we do not know whether it is strong enough to override strong interpersonal incentives such as affective touch. Thus, this neuroimaging study investigated whether touch reward is influenced by one’s metabolic state. In a within-subject study, 60 participants (16 women) remained once fasted, while they started the other test session with a standardized meal. All rated pleasantness and stimulus intensity for slow (0.3cm/s), CT-targeted (3cm/s), and fast (30cm/s) touch applied to the right shin. For 45 participants (11 women), 3T fMRI data were collected during touch processing. Touch was rated as more pleasant when participants were satiated than when fasted. Additionally, participants rated CT-targeted touch as most pleasant. In accordance, brain activation was enhanced in the right supramarginal gyrus and bilateral paracingulate areas during CT-targeted touch when participants were satiated compared to fasted (cluster-level FWE-corrected p