Orbitofrontal cortex mediates pain inhibition by monetary reward

Becker, S., Gandhi, W. ORCID: https://orcid.org/0000-0003-3796-6311, Pomares, F., Wager, T. D. and Schweinhardt, P. (2017) Orbitofrontal cortex mediates pain inhibition by monetary reward. Social Cognitive and Affective Neuroscience, 12 (4). pp. 651-661. ISSN 1749-5024 doi: 10.1093/scan/nsw173

Abstract/Summary

Pleasurable stimuli, including reward, inhibit pain, but the level of the neuraxis at which they do so and the cerebral processes involved are unknown. Here, we characterized a brain circuitry mediating pain inhibition by reward. Twenty-four healthy participants underwent functional magnetic resonance imaging while playing a wheel of fortune game with simultaneous thermal pain stimuli and monetary wins or losses. As expected, winning decreased pain perception compared to losing. Inter-individual differences in pain modulation by monetary wins relative to losses correlated with activation in the medial orbitofrontal cortex (mOFC). When pain and reward occured simultaneously, mOFCs functional connectivity changed: the signal time course in the mOFC condition-dependent correlated negatively with the signal time courses in the rostral anterior insula, anterior-dorsal cingulate cortex and primary somatosensory cortex, which might signify momentto-moment down-regulation of these regions by the mOFC. Monetary wins and losses did not change the magnitude of pain-related activation, including in regions that code perceived pain intensity when nociceptive input varies and/or receive direct nociceptive input. Pain inhibition by reward appears to involve brain regions not typically involved in nociceptive intensity coding but likely mediate changes in the significance and/or value of pain.