Input minimization: a model of cerebellar learning without climbing fiber error signals.
The cerebellum is critical for motor learning. Current cerebellar learning models follow the Marr/Albus paradigm, in which climbing fibers provide error signals that shape plastic synapses between parallel fibers and Purkinje cells. However, climbing fibers have slow and largely random discharge, and seem unlikely to provide error signals with resolution sufficient to guide cerebellar learning. Parallel fibers carry error signals and could direct the plasticity of their own synapses, but the error signals are carried along with other signals. This report presents the new input minimization (InMin) model, in which Purkinje cells reduce error by minimizing their overall parallel fiber input. The slowly, randomly firing climbing fiber provides only synchronization pulses. InMin offers an alternative that can unify cerebellar findings.
Anastasio
T J
TJ
Department of Molecular and Integrative Physiology, Beckman Institute, University of Illinois at Urbana/Champaign, 405 North Mathews Ave, Urbana, IL 61801, USA.
D000200:Action Potentials / Q000502:physiology; D000222:Adaptation, Physiological / Q000502:physiology; D000465:Algorithms; D000818:Animals; D006801:Humans; D007858:Learning / Q000502:physiology*; D008959:Models, Neurological; D009068:Movement / Q000502:physiology*; D016571:Neural Networks, Computer; D009434:Neural Pathways / Q000166:cytology / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology*; D009847:Olivary Nucleus / Q000166:cytology / Q000502:physiology*; D017729:Presynaptic Terminals / Q000502:physiology* / Q000648:ultrastructure; D011689:Purkinje Cells / Q000166:cytology / Q000502:physiology*; D012027:Reflex, Vestibulo-Ocular / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology