Paraventricular thalamic inputs to the ventral pallidum shape reward seeking during threat and fear responding in extinction.

Abstract

Environmental threats are typically encountered when animals are searching for food and other necessities. Adaptive behavior must balance competition between fear behavior and reward seeking. We gave rats local neuronal deletions of the ventral pallidum (VP) or specifically deleted paraventricular thalamic nucleus (PVT) neurons projecting directly to the VP. Rats were then assessed in a conditioned suppression procedure in which cues predicting unique foot shock probabilities were presented during, but independent from, reward seeking. Foot shock introduction generally suppressed reward seeking in rats, and recovery from shock introduction was facilitated in rats with VP or PVT → VP pathway deletions. Discriminative fear was observed in controls, and this fear responding reduced over a single extinction session. VP deletion enhanced extinction fear responding, and PVT → VP pathway deletion abolished within-session fear reductions. The results demonstrate the VP and its inputs from the PVT shape reward seeking in threat settings and govern fear extinction responding. (PsycInfo Database Record (c) 2025 APA, all rights reserved).