Neural basis of sexually dimorphic decision-making

Animals continually arbitrate between incompatible behaviors: whether to feed or flee, mate or fight, sleep or explore. The brain must select, suppress, and sequence actions according to sensory inputs, internal state, and likely success. Sexual dimorphism adds complexity: males and females face distinct reproductive pressures and often resolve conflicts in divergent ways. Yet the neural mechanisms underlying sex-specific prioritization remain poorly understood. Drosophila melanogaster offers a powerful model for dissecting action selection at cellular and circuit resolution. Here, we synthesize recent advances revealing how sexually dimorphic neurons act as integrator hubs, combining sensory cues with internal states to bias choice in both sexes. Neuromodulators confer flexibility, dynamically reweighting priorities as circumstances shift. Dopamine, in particular, filters distracting stimuli and tunes evidence accumulation, enabling priorities to update as goals approach. These studies outline emerging principles of action selection across contexts and sexes and suggest conserved strategies for balancing drives across species.