Intracranial recordings in humans reveal differential contributions of medial and lateral orbitofrontal cortex to approach-avoidance decision-making.

Approach-avoidance refers to the psychological conflict in which deciding to approach a reward also carries potential punishment. The orbitofrontal cortex (OFC) is proposed to arbitrate approach-avoidance decisions, yet little is known about the real-time computations within OFC during these decisions. We conducted intracranial recordings in humans implanted with stereotactic electroencephalography electrodes in the OFC while they played a gamified approach-avoidance task. Here we identified two anatomically distinct signals within the OFC prior to approach: an increase in activity within the medial compartment and a decrease within the lateral compartment. Prior to decisions, these signals rapidly alternated between discrete pro-approach and pro-avoidant states, thus introducing a new functional architecture within the human OFC during decision-making.