Neuroimaging Illuminates How Gratitude Lights Up the Brain
A new fMRI study identifies the brain mechanics of gratitude and giving back.
Posted May 09, 2018
Altruism and gratitude are two sides of the same coin. However, until recently it was unclear how altruism from a benefactor translated into gratefulness in the brain of a beneficiary. On May 7, a new paper, “Decomposing Gratitude: Representation and Integration of Cognitive Antecedents of Gratitude in the Brain,” was published in the Journal of Neuroscience. This research provides fMRI-based evidence of the neural correlates associated with feelings of gratitude and the brain mechanics of reciprocity.
For this study, Xiaolin Zhou and colleagues at the Center for Brain and Cognitive Sciences at Peking University in Beijing set out to pinpoint the trial-by-trial neurocognitive process that leads to gratitude.
To investigate this research question, Zhou et al. designed a socially interactive game that could be played in a brain scanner. During this game, one player could pay a specific sum of money to prevent another player from receiving a painful shock. At various stages of play, both the degree of pain intensity and the cost of preventing an electric shock to another player were manipulated to make it more or less expensive to be altruistic and help someone else avoid pain.
As the authors explain, “By independently manipulating monetary cost and the degree of pain reduction, we could identify the neural signatures of benefactor's cost and recipient's benefit and examine how they were integrated.”
Notably, the researchers found that being a potential benefactor—who was in a position to be altruistic and relieve someone else's pain at a cost—activated brain regions involved in mentalizing (e.g., temporoparietal junction). On the flip side, being the beneficiary of pain relief was encoded in reward-sensitive brain regions (e.g., ventral striatum).
Sometimes, when a player’s pain was relieved, the beneficiary didn’t know that another player had made a sacrifice to stop the electric shock. As would be expected, when a player was aware that his or her pain reduction was the direct result of another player being altruistic, it triggered varying degrees of gratitude.
The intensity of someone's gratitude was correlated with the perigenual anterior cingulate cortex (pgACC) lighting up to varying degrees in the fMRI. As you can see in the image at the top of the page, the ACC looks like a "collar" surrounding the frontal part of the corpus callosum, which connects the left and right cerebral hemispheres.
The latest findings by Xiaolin Zhou and colleagues suggest that the pgACC plays an integrative role in generating gratitude. Additionally, the researchers speculate that the gyral ACC plays an intermediary role in converting gratitude into reciprocal gestures of thankfulness.
Hongbo Yu, Xiaoxue Gao, Yuanyuan Zhou and Xiaolin Zhou. “Decomposing gratitude: representation and integration of cognitive antecedents of gratitude in the brain.” The Journal of Neuroscience (Published: May 7, 2018) DOI: 10.1523/JNEUROSCI.2944-17.2018