• We use a simple gambles design in an fMRI study to compare two conditions: ambiguity and conflict.

• Participants were more conflict averse than ambiguity averse.

• Ambiguity aversion did not correlate with conflict aversion.

• Activation in the medial prefrontal cortex correlated with ambiguity level and ambiguity aversion.

• Activation in the ventral striatum correlated with conflict level and conflict aversion.

Studies of decision making under uncertainty generally focus on imprecise information about outcome probabilities (“ambiguity”). It is not clear, however, whether conflicting information about outcome probabilities affects decision making in the same manner as ambiguity does. Here we combine functional magnetic resonance imaging (fMRI) and a simple gamble design to study this question. In this design the levels of ambiguity and conflict are parametrically varied, and ambiguity and conflict gambles are matched on expected value. Behaviorally, participants avoided conflict more than ambiguity, and attitudes toward ambiguity and conflict did not correlate across participants. Neurally, regional brain activation was differentially modulated by ambiguity level and aversion to ambiguity and by conflict level and aversion to conflict. Activation in the medial prefrontal cortex was correlated with the level of ambiguity and with ambiguity aversion, whereas activation in the ventral striatum was correlated with the level of conflict and with conflict aversion. These novel results indicate that decision makers process imprecise and conflicting information differently, a finding that has important implications for basic and clinical research.

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Notes/Citation Information

Published in Frontiers in Behavioral Neuroscience, v. 9, article 325, p. 1-15.

© 2015 Pushkarskaya, Smithson, Joseph, Corbly and Levy.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

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Funding Information 

This research was supported by Grants P50 DA005312, R01 HD052724, R01 AG033406, and P20 RR015592 from the Research Foundation of the University of Kentucky and from the National Institutes of Health.

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