FEAST OR FRIENDSHIP: HOW THE BRAIN PRIORITIZES COMPETING NEEDS

Animals continuously balance competing physiological needs by prioritizing behaviors essential for survival. Despite the critical importance of need prioritization, the neuronal and molecular mechanisms remain poorly understood. Since oxytocin (OXT) modulates both social and feeding behaviors, we hypothesized that hypothalamic OXT neurons play a key role in governing preference between social interaction and food needs under competing demands. To test this, we used a recently established Social versus Food Preference test in adult CD1 male mice, manipulating social and metabolic states through housing conditions and food deprivation. Regardless of housing, all mice initially preferred social stimuli over food stimuli. However, as caloric need increased, group-housed mice shifted their preference toward food, whereas single-housed mice maintained equal preference for both stimuli, reflecting behavioral indecision when both needs remained unmet. Immunofluorescence revealed that oxytocin neuronal activity in the paraventricular nucleus (PVN) correlated with stimulus preference, with reduced PVN-OXT activity in the food-preferring group and increased activity in the social-preferring group. Additionally, animals showing strong preference exhibited lower neuronal activity in the bed nucleus of the stria terminalis (BNST) and higher activity in the basolateral amygdala (BLA). Circuit-tracing identified that both BLA and BNST regions receive input from a common upstream region, the paraventricular thalamus (PVT). Notably, animals with strong social preference showed heightened activity in PVT→BLA projecting neurons and chemogenetic inhibition of this pathway biased animals towards food preference. Together, these findings suggest that PVN-OXT activity and a PVT→BLA circuit jointly modulate behavioral prioritization between competing social and metabolic needs.