The olivocerebellar system differentially encodes the effect sensory events exert on behavior

Inferior olive neurons convey information about sensorimotor events via climbing fibers (CFs) to the cerebellum, but their functional significance remains unclear. Here, we image CF axonal terminals in the cerebellum during a task that exposes mice to force perturbation, movement instruction, and reward; each followed by multiple modes of motor activity. CF activations by sensory events are found to be either generic or informative about the consequences the encoded event has on behavior. The number of informative cells and the information strength are regulated by event modality and the functional complexity of the cell's activity. We additionally find that CFs carry probabilistic information about behavioral context during idle waiting periods. Our findings reveal properties of olivary neurons that are key to defining their function in the cerebellum-dependent control of behavior. They suggest that the inferior olive flexibly instructs the cerebellum of any process that may shape an animal's action.