Encoding Predictive Reward Value in Human Amygdala and Orbitofrontal Cortex

TLDR

Adaptive behavior is optimized in organisms that maintain flexible representations of the value of sensory‑predictive cues. The study aims to identify central representations of predictive reward value in humans using reinforcer devaluation and fMRI. Participants viewed two arbitrary visual stimuli before and after olfactory devaluation in an appetitive conditioning paradigm while fMRI recorded neural activity. Amygdala and orbitofrontal cortex activity decreased for devalued predictive cues but remained unchanged for nondevalued cues, indicating these regions encode current reward value.

Abstract

Adaptive behavior is optimized in organisms that maintain flexible representations of the value of sensory-predictive cues. To identify central representations of predictive reward value in humans, we used reinforcer devaluation while measuring neural activity with functional magnetic resonance imaging. We presented two arbitrary visual stimuli, both before and after olfactory devaluation, in a paradigm of appetitive conditioning. In amygdala and orbitofrontal cortex, responses evoked by a predictive target stimulus were decreased after devaluation, whereas responses to the nondevalued stimulus were maintained. Thus, differential activity in amygdala and orbitofrontal cortex encodes the current value of reward representations accessible to predictive cues.