title: Reward value comparison via mutual inhibition in ventromedial prefrontal cortex.
abstract: Recent theories suggest that reward-based choice reflects competition between value signals in the ventromedial prefrontal cortex (vmPFC). We tested this idea by recording vmPFC neurons while macaques performed a gambling task with asynchronous offer presentation. We found that neuronal activity shows four patterns consistent with selection via mutual inhibition: (1) correlated tuning for probability and reward size, suggesting that vmPFC carries an integrated value signal; (2) anti-correlated tuning curves for the two options, suggesting mutual inhibition; (3) neurons rapidly come to signal the value of the chosen offer, suggesting the circuit serves to produce a choice; and (4) after regressing out the effects of option values, firing rates still could predict choice-a choice probability signal. In addition, neurons signaled gamble outcomes, suggesting that vmPFC contributes to both monitoring and choice processes. These data suggest a possible mechanism for reward-based choice and endorse the centrality of vmPFC in that process.
authors.affiliation: Department of Brain and Cognitive Sciences, Center for Visual Science, University of Rochester, Rochester, NY 14627, USA. Electronic address: cstrait@bcs.rochester.edu.
authors.forename: Caleb E
authors.initials: CE
authors.lastname: Strait
authors.affiliation: Department of Brain and Cognitive Sciences, Center for Visual Science, University of Rochester, Rochester, NY 14627, USA.
authors.forename: Tommy C
authors.initials: TC
authors.lastname: Blanchard
authors.affiliation: Department of Brain and Cognitive Sciences, Center for Visual Science, University of Rochester, Rochester, NY 14627, USA.
authors.forename: Benjamin Y
authors.initials: BY
authors.lastname: Hayden
mesh_terms: D000818:Animals; D002755:Choice Behavior / Q000502:physiology*; D008253:Macaca mulatta; D008297:Male; D009433:Neural Inhibition / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D017397:Prefrontal Cortex / Q000502:physiology*; D011897:Random Allocation; D012201:Reward