Social Comparison Important in Brain's Reward Processing
Ventral striatum of brain appears to be involved
FRIDAY, Nov. 30 (HealthDay News) -- Receiving a larger monetary reward compared to a peer is associated with increased activity in the ventral striatum of the brain seen on functional MRI (fMRI), providing evidence for the importance of social comparison in reward processing, according to an article published in the Nov. 23 issue of Science.
Klaus Fliessbach, M.D., of the Life and Brain Center Bonn in Bonn, Germany, and colleagues investigated the impact of social comparison on reward-related brain activity measured by fMRI. Pairs of human subjects in adjacent MRI scanners were asked perform a dot-counting exercise that entailed monetary rewards for correct answers. After each trial, the subjects, 19 pairs in all, were given immediate feedback on both partners' accuracy and monetary payment.
The researchers found that participants' awareness of their partner's monetary reward relative to their own affected blood oxygen level-dependent (BOLD) responses in the ventral striatum seen on fMRI. Receiving a larger relative payment than another subject was associated with a stronger BOLD signal in this brain area, irregardless of the absolute payment amount.
The authors conclude, "Our results provide neurophysiological evidence for the importance of social comparison on reward processing in the human brain."