Behavioral/Systems/Cognitive The Neural Correlates of Subjective Utility of Monetary Outcome and Probability Weight in Economic and in Motor Decision under

In decision under risk, people choose between lotteries that contain a list of potential outcomes paired with their probabilities of occurrence. We previously developed a method for translating such lotteries to mathematically equivalent “motor lotteries. ” The prob-ability of each outcome in amotor lottery is determined by the subject’s noise in executing amovement. In this study, we used functional magnetic resonance imaging in humans to compare the neural correlates of monetary outcome and probability in classical lottery tasks inwhich informationaboutprobabilitywas explicitly communicated to the subjects and inmathematically equivalentmotor lottery tasks inwhich probability was implicit in the subjects ’ ownmotor noise.We found that activity in themedial prefrontal cortex (mPFC) and the posterior cingulate cortex quantitatively represent the subjective utility of monetary outcome in both tasks. For probability, we found that themPFC significantly tracked the distortion of such information in both tasks. Specifically, activity inmPFC represents probability information but not the physical properties of the stimuli correlatedwith this information. Together, the results demonstrate thatmPFC represents probability from two distinct forms of decision under risk