Orbitofrontal cortex contributes to the comparison of values underlying economic choices

Economic choices between goods entail the computation and comparison of subjective values. Previous studies examined neuronal activity in the orbitofrontal cortex (OFC) of monkeys choosing between different types of juices. Three groups of neurons were identified: offer value cells encoding the value of individual offers, chosen juice cells encoding the identity of the chosen juice, and chosen value cells encoding the value of the chosen offer. The encoded variables capture both the input (offer value) and the output (chosen juice, chosen value) of the decision process, suggesting that values are compared within OFC. Recent work demonstrates that choices are causally linked to the activity of offer value cells. Conversely, the hypothesis that OFC contributes to value comparison has not been confirmed. Here we show that weak electrical stimulation of OFC specifically disrupts value comparison without altering offer values. This result implies that neuronal populations in OFC participate in the decision process. Significance Economic choices encompass two mental stages: values are assigned to the available offers, and a decision is made by comparing values. Previous work showed that choices are causally related to offer values encoded in the orbitofrontal cortex (OFC). Conversely, the neural underpinnings of value comparison remain poorly understood. Here we show that weak electrical stimulation of OFC selectively disrupts the decision process without affecting offer values. Hence, neurons in OFC contribute to value comparison.