A neural circuit for flexible control of persistent behavioral states

To adapt to their environments, animals must generate behaviors that are
closely aligned to a rapidly changing sensory world. However, behavioral
states such as foraging or courtship typically persist over long time
scales. It remains unclear how neural circuits generate persistent
behavioral states while maintaining flexibility to switch states when the
context changes. Here, we elucidate the architecture of a circuit
controlling the choice between roaming and dwelling foraging states in C.
elegans. Through ensemble-level calcium imaging in freely-moving animals,
we identify stable, circuit-wide activity patterns corresponding to each
state. Mutual inhibition between two neuromodulatory systems underlies the
persistence and mutual exclusivity of the opposing network states. We
identify a sensory processing neuron that transmits information about food
odors to both the roaming and dwelling circuits, biasing the animal
towards different states in different contexts. These findings reveal a
circuit architecture that enables flexible, sensory-driven control of
persistent behavioral states.