News & Seminars

Xiaolin Zhou’s group at the PKU-IDG/McGovern Institute for Brain Research, Department of Psychology and Center for Life Sciences at Peking University have recently published a paper on Human Brain Mapping (Volume 37, Issue 5, May 2016) titled ‘COMT Val158Met polymorphism influences the susceptibility to framing in decision-making: OFC-amygdala functional connectivity as a mediator’. They demonstrated the involvement of COMT Val158Met polymorphism in the framing effect in decision-making and suggested resting-state functional connectivity between OFC and amygdala as a neural mediator underlying this gene–behavior association. This paper was accepted as cover article for this issue of Human Brain Mapping.

 

Individuals tend to avoid risk in a gain frame, in which options are presented in a positive way, but seek risk in a loss frame, in which the same options are presented negatively. Previous studies suggest that emotional responses play a critical role in this “framing effect.” Given that the Met allele of COMT Val158Met polymorphism (rs4680) is associated with the negativity bias during emotional processing, this study investigated whether this polymorphism is associated with individual susceptibility to framing and which brain areas mediate this gene–behavior association. Participants were genotyped, scanned in resting state, and completed a monetary gambling task with options (sure vs risky) presented as potential gains or losses. The Met allele carriers showed a greater framing effect than the Val/Val homozygotes as the former gambled more than the latter in the loss frame. Moreover, the gene–behavior association was mediated by resting-state functional connectivity (RSFC) between orbitofrontal cortex (OFC) and bilateral amygdala. Met allele carriers showed decreased RSFC, thereby demonstrating higher susceptibility to framing than Val allele carriers. These findings contribute to our understanding of the individual differences in irrational decision-making.

 

Figure 1. Neural correlates underlying the gene-behavior association.


Figure 2. Cover illustration. In this Chinese-style painting, the two dragons with “DNA” horns represent the chromosomes of Val allele carriers (left) and Met allele carriers (right), respectively. The money in the left dragon’s hand represents its tendency to choose the sure gain option, and the dice in the right dragon’s hand represents its tendency to choose the gamble option. The functional connectivity between OFC and bilateral amygdala is shown in the middle of the two dragons representing its mediation role in this gene-behavior association. The idea of this painting comes from the ancient Chinese myth, “Two dragons play with a pearl”, which is representative of good luck and happiness.

 

Figure 3. The association between COMT Val158Met polymorphism and the susceptibility to framing in decision-making. Individuals with the Met allele, which is associated with lower activity of COMT, were more susceptible to framing than the Val/Val homozygotes.


Figure 4. The mediation analysis. The effect of the COMT Val158Met polymorphism on individual susceptibility to framing was mediated by OFC-amygdala functional connectivity.

 

This study was supported by National Basic Research Program of China (973 Program), Natural Science Foundation of China and China Postdoctoral Science Foundation.

 

Xiaoxue Gao#, Pingyuan Gong#, Jinting Liu#, Jie Hu, Yue Li, Hongbo Yu, Xiaoliang Gong, Yang Xiang, Changjun Jiang, Xiaolin Zhou*. COMT Val158Met polymorphism influences the susceptibility to framing in decision-making: OFC‐amygdala functional connectivity as a mediator. Hum Brain Mapp, 2016, 37: 1880-1892.