HIPPOCAMPAL–HYPOTHALAMIC INTEGRATION OF TERRITORIAL CONTEXT

Territorial competition requires animals to distinguish locations associated with safety or threat, yet the circuit mechanisms supporting such contextual mapping remain unclear. We investigated how the ventrolateral ventromedial hypothalamus (VMHvl) - a key hub for aggression and avoidance - integrates territorial experience to guide agonistic decisions. Using a semi-naturalistic arena, we allowed hybrid mice to establish adjacent territories and recorded VMHvl neurons at single-cell resolution while animals were exposed to different social contexts (dominance/win, subordination/loss, neutral‑associated). Behaviourally, agonistic responses depend on context: mice modulate aggression when tested in their own territory versus in a competitor's. Preliminary analyses indicate that subsets of VMHvl neurons respond to transitions between territorial zones, suggesting the emergence of context-specific activity patterns. Ongoing work is assessing how these representations evolve with social conflict and whether they differ across dominance hierarchies. To test the contribution of hippocampal inputs to this context-induced neuroplasticity, we chemogenetically silenced ventral CA1 (vCA1) neurons after competition and assessed agonistic behaviours across contexts. Early observations suggest a possible reduction in contextual regulation of aggression in dominant animals. In a complementary experiment, we use Fos2A iCreER (TRAP2) mice to label and reactivate vCA1 ensembles engaged in either the home territory or the adjacent competitor’s territory. The data points to the presence of distinct context-responsive populations, and ongoing experiments will evaluate how these subpopulations contribute to context-associated behavioural responses. Together, these studies aim to elucidate how hippocampal–hypothalamic interactions contribute to the construction of territorial maps that support adaptive agonistic behaviour.