Deconstructing the Role of Expectations in Cooperative Behavior with Decision Neuroscience

Abstract

This project attempts to understand the role of expectations in cooperative behavior using the interdisciplinary approach of Decision Neuroscience. While cooperation provides the foundation for a successful society, the underlying bio-psycho-social mechanisms remain surprisingly poorly understood. This investigation deconstructs cooperation into the specific behaviors of trust, reciprocation, and norm enforcement using the Trust and Ultimatum Games from behavioral economics and combines formal modeling and functional magnetic resonance imaging to understand the neurocomputational role of expectations in these behaviors. The results indicate that people appear to use context specific shared expectations when making social decisions. These beliefs are malleable and appear to be dynamically updated after an interaction. Emotions such as guilt and anger can be formally operationalized in terms of others' expectations and appear to be processed by a specific neural system involving the anterior insula, anterior cingulate cortex, and supplemental motor cortex. Importantly, these neural signals appear to motivate people to not only behave consistent with these expectations, but also to help others update their beliefs when these expectations are violated. Further, violations of social expectations appear to promote enhanced memory for norm violators. This work demonstrates the neural and computational basis of moral sentiments.