Talk Title: A coming-of-age story: neuronal circuit function in early life

Talk Abstract: How is the brain built? Even very early in life, developing neuronal circuits are active, responsive to sensory inputs, and drive behavior. Such early life circuit functions both guide circuit formation and also support early social and survival behaviors. This is akin to flying an airplane while still building it. How do developing circuits, despite rapidly changing structure, drive coherent and age-appropriate behaviors? To address this, I focused on the hypothalamic preoptic area. The preoptic area is critical for homeostatic control and social behavior, functions that change dramatically from infancy to adulthood. I established a developmental transcriptomic atlas of ~150 preoptic cell types, including dozens involved in distinct homeostatic and social functions, uncovering (1) surprisingly early cell type diversity; (2) a mosaic pattern in which, at any given age, some cell types are more mature than others, correlating with the maturation of distinct behaviors; and (3) a putative critical period in early infancy, when social experience affects social behavior circuit maturation. These findings lay the foundation for ongoing and future investigations of neuronal circuits underlying social behavior, sleep, and other functions in early life.