Oscillations Synchronize Amygdala-to-Prefrontal Primate Circuits during Aversive Learning

The contribution of oscillatory synchrony in the primate amygdala-prefrontal pathway to aversive learning remains largely unknown. We found increased power and phase synchrony in the theta range during aversive conditioning. The synchrony was linked to single-unit spiking and exhibited specific directionality between input and output measures in each region. Although it was correlated with the magnitude of conditioned responses, it declined once the association stabilized. The results suggest that amygdala spikes help to synchronize ACC activity and transfer error signal information to support memory formation. Taub et al. report increased synchrony between amygdala's output (spikes) and prefrontal's input (local field potentials) that is locked to theta band and declines once memory is formed. Therefore, the primate amygdala→prefrontal pathway uses theta to transfer error-like information during fear learning.