Based on Barrett’s concept, we define emotion as a subjective, conscious experience characterized by biological reaction and mental states. According to her conceptual act theory ( Barrett, 2006, 2013 Barrett and Kensinger, 2010), physical states and actions can be transformed into different emotion expressions under different social contexts. Barrett (2012) suggested that emotions were both biologically evident and socially constructed. What is the distinction between emotion and reason? This question is as old as psychological science itself. The heart has its reasons which reason does not know. We then illustrate how cognition modulates emotion and how they cooperate to affect decision making. Specifically, in our model, we identify factors that determine when emotions override reason and delineate the type of contexts in which emotions help or hurt decision making. Here, drawing findings from behavioral economics and neuroeconomics, we provide a new model, labeled “The interactive influence model of emotion and cognition,” to elaborate the relationship of emotion and reason in decision making. However, from Darwin’s evolutionary perspective, emotion is adaptive, guiding us to make sound decisions in uncertainty. The reason system (in “the head”) reins in our impulses (from “the heart”) and overrides our snap judgments. Decision making is perceived as the competition between an emotion system that is automatic but prone to error and a reason system that is slow but rational. Following Plato’s description of emotion and reason as two horses pulling us in opposite directions, modern dual-system models of decision making endorse the antagonism between reason and emotion. The experience of emotion has a powerful influence on daily-life decision making. 2School of Economics and Management and Scientific Laboratory of Economic Behaviors, South China Normal University, Guangzhou, China.1School of Psychology and Center for Studies of Psychological Application, South China Normal University, Guangzhou, China.

Affective decision making