Seeking Ambiguity: a Review on Neuroimaing Studies on Decision Making under Ambiguity

Recent developments of neuroimaging technology enable us to investigate the brain network implicated in economical decision making(Glimcher et al. 2004; Camerer 2008). One of the fascinating topic is "ambiguity aversion" where people tend to avoid unknown options as demonstrated by Ellsberg paradox. Although "ambiguity aversion" has been consistently observed in a variety of situations, uncertainty due to incomplete knowledge can be resolved by obtaining missing information, and people explore the ambiguous options as well. Here, we review a number of neuroimaging studies on "ambiguity aversion" and associated works. It has been shown that the affective OFC and the cognitive prefrontal cortex play a crucial role in decision making under uncertainty. We discuss what kinds of cognitive function are involved in the decision making process by overviewing neuroimaing studies on higher cognitive processes in general including exploratory behavior.