A multilayered gap junction network is essential for social decision-making

Early-life social experiences can shape adult behavior, yet the underlying neural mechanisms of this plasticity remain incompletely understood. Here, we show that <i>Caenorhabditis elegans</i> larvae reared at high density develop into adults that exhibit exploratory behavior in the associative-learning paradigm known as thermotaxis. While animals grown at low density prefer the temperature previously associated with food, those exposed to high density during larval stages instead disperse from this temperature. The high-density experience alters the neural representation of thermal valence, a process that requires a gap junction network spanning multiple neural circuit layers. This network connects density-sensing neurons to the circuit that processes temperature information. Furthermore, these gap junction components also control the decision to enter developmental diapause in response to high density. Our results suggest that the multilayered gap junction network enables early social experience to influence adult behavior and is essential for developmental and behavioral plasticity in social contexts.