What is a neural circuit made of?: Cell-type diversity - The nervous system is spectacularly specialized, with dedicated neural circuits tailored to hear the difference between B and B#, read micro expressions on a friend's face, catch a ball, remember your childhood address, and much more. Specific neural circuits underlie each of these complex tasks, and their constituent neurons shape how information is processed to drive behavior. We are interested in how genetic programs sculpt the functional properties of each neuronal cell type, and how these properties dictate its role in the circuit.