Different forms and degrees of uncertainty, such as risk (known probabilities) and ambiguity (unknown probabilities), create quantitatively different signals about choice outcomes. Our goal is to establish a link between sensitivity to risk, ambiguity and physiological arousal to choice. By identifying a discrete emotional signal that may differentially contribute to the value of computation for ambiguous decisions over risky decisions, we aim to identify and classify the behavioral and neural correlates of decision-making under uncertainty.