Graded error signals in eyeblink conditioning.
Minimizing errors is an important aspect of learning. However, it is not enough merely to record if an error occurred. For efficient learning, information about the magnitude of errors is critical. Did my tennis swing completely miss the target or did I hit the ball, but not quite in the sweet spot? How can neurons - which have traditionally been thought of as binary units - signal the magnitude of an error? Here I review evidence that eyeblink conditioning - a basic form of motor learning - depends on graded signals from the inferior olive which guides plasticity in the cerebellum and ultimately tunes behavior. Specifically, evidence suggests that: (1) Error signals are conveyed to the cerebellum via the inferior olive; (2) Signals from the inferior olive are graded; (3) The strength of the olivary signal affects learning; (4) Cerebellar feedback influences the strength of the olivary signal. I end the review by exploring how graded error signals might explain some behavioral learning phenomena.
['Rasmussen|Anders|A|']
D000818:Animals D002531:Cerebellum D003215:Conditioning, Eyelid D006801:Humans D007858:Learning D009043:Motor Activity D009434:Neural Pathways D009474:Neurons D009847:Olivary Nucleus
Error signals Eyeblink conditioning Learning Inferior olive Plasticity Cerebellum Climbing fibers Nucleo-Olivary pathway Rescorla-Wagner