The Neurocomputational Mechanism Underlying Decision-Making on Unfairness to Self and Others
Lanxin Luo1,2,3,4 · Han Xu1,2,3,4 · Xia Tian1,2,3,4 · Yue Zhao1,2,3,4 · Ruoling Xiong1,2,3,4 · Huafeng Dong1,2,3,4 · Xiaoqing Li1,2,3,4 · Yuhe Wang1,2,3,4 · Yue‑Jia Luo5,6,7 · Chunliang Feng1,2,3,41 Key Laboratory of Brain, Cognition and Education Sciences (South China Normal University), Ministry of Education, Guangzhou 510631, China
2 School of Psychology, South China Normal University, Guangzhou 510631, China
3 Center for Studies of Psychological Application, South China Normal University, Guangzhou 510631, China
4 Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou 510631, China
5 Institute for Neuropsychological Rehabilitation, University of Health and Rehabilitation Sciences, Qingdao 266113, China
6 School of Psychology, Shenzhen University, Shenzhen 518061, China
7 State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China
Abstract
Fairness is a fundamental value in human societies, with individuals concerned about unfairness both to themselves and to others. Nevertheless, an enduring debate focuses on whether self-unfairness and other-unfairness elicit shared or distinct neuropsychological processes. To address this, we combined a three-person ultimatum game with computational modeling and advanced neuroimaging analysis techniques to unravel the behavioral, cognitive, and neural patterns underlying unfairness to self and others. Our behavioral and computational results reveal a heightened concern among participants for self-unfairness over other-unfairness. Moreover, self-unfairness consistently activates brain regions such as the anterior insula, dorsal anterior cingulate cortex, and dorsolateral prefrontal cortex, spanning various spatial scales that encompass univariate activation, local multivariate patterns, and whole-brain multivariate patterns. These regions are well-established in their association with emotional and cognitive processes relevant to fairness-based decision-making. Conversely, other-unfairness primarily engages the middle occipital gyrus. Collectively, our findings robustly support distinct neurocomputational signatures between self-unfairness and other-unfairness.
Keywords
Fairness; Three-person ultimatum game; fMRI; Computational model; Multivoxel pattern analysis
