Choice-driven remapping of action- and stimulus-anchored value in human single neurons

Whether stimulus- and action-based choices rely on a shared neural architecture remains intensely debated. While lesion and fMRI studies show conflicting regional dissociation and overlap, the underlying single neuron substrates remain unknown. We recorded single neuron activity from the human ventromedial prefrontal cortex (vmPFC), anterior cingulate cortex (ACC), pre-supplementary motor area (preSMA), and amygdala during distinct action- and stimulus-based reward tasks. Prior to decision-making, neurons across all regions broadly encode value for both choice domains. However, choice commitment triggers domain segregation across the prefrontal cortex. While ACC and vmPFC neurons flexibly track both chosen actions and stimuli, they exhibit a double dissociation for chosen valuation: ACC neurons selectively maintain action-based values, whereas vmPFC neurons selectively maintain stimulus-based values. Conversely, preSMA neurons invariant to task domain track chosen action identity and value. These findings reveal how prefrontal networks transition from domain-general evaluation to domain-segregated choice execution.