Another individual’s distress can provoke withdrawal and avoidance behaviors, yet, in social species, it can also motivate approach and caregiving behavior. In this issue, Geng et al. identified a vasopressin-sensitive neuronal circuit that converts distress signals from a cagemate into caregiving-like behavior in mice. Using fiber photometry, electrophysiological recordings, and optogenetic activation to dissect this circuit, they showed that vasopressin neurons in the paraventricular hypothalamus recruit vasopressin 1a receptor–expressing (V1aR-expressing) neurons in the medial central amygdala, which engage the ventral tegmental area to promote allogrooming and injury-directed licking. The findings link emotional state matching, prosocial action, reinforcement, and stress relief, while raising important questions about circuit specificity, sex as a biological variable, and translation.
Jonathan P. Fadok