The neuroscience of dual (and triple) systems in decision making.

Samantha Marie Waters Wood

Abstract: With the emergence of functional neuroimaging and the field of neuroeconomics, the debate about “single system” or “dual system” models for valuation is beginning to intensify. Proponents of a single system for valuation maintain that one neural region is devoted to evaluating costs and rewards, while dual system models argue decision making is a balance between fast, impulsive processing and slow, reflective processes. Using evidence from the clinical side of the argument, we will argue in this chapter that not only are the traditional two processes supported by the clinical facts, but in addition the evidence points to a third process, thus calling for the notion of “triple process” models. We also will highlight the importance of a third neural system that translates homeostatic, bodily signals into feelings of craving, which in turn modifies the dynamics of the traditional dual systems.