The anterior paraventricular thalamus counteracts fear expression during retrieval through both amygdala and subiculum circuits
摘要
During fear memory recall, the concurrent suppression of passive freezing and promotion of active coping behaviors represents a crucial survival strategy, yet its neural basis remains unclear. Employing activity-dependent neuronal mapping, we identified consistent activation in the anterior paraventricular thalamus (PVA) during recall across retrieval timepoints. Manipulation of PVA glutamatergic neurons during recall bidirectionally modulated fear responses, exhibiting an effect opposite to that of the posterior paraventricular thalamus. Distinct PVA subpopulations project to the basolateral amygdala (BLA) and ventral subiculum (vSub). Projection-specific activation of either pathway recapitulated the PVA-mediated suppression of fear. However, an alternative platform-searching test revealed the functional divergence of these two circuits. The PVA-vSub circuit promoted exploratory behaviors during recall, whereas the PVA-BLA pathway was involved in memory retrieval. Collectively, PVA serves as a key hub in defensive strategy selection during fear memory recall, coordinating fear suppression and active exploration through parallel downstream circuits.