climbing fiber

noun

anatomy

: any of the afferent nerve fibers arising from neurons in the inferior olive that ascend to the cerebellar cortex to synapse with Purkinje cells

The olive sends so-called climbing fibers up to the cerebellum where they wrap around Purkinje cells like vines around a tree, exerting a powerful influence on them …

—Ingrid Wickelgren, Science, 11 Sept. 1998

Individual Purkinje neurons receive synaptic input from only a single climbing fiber, whereas each climbing fiber contacts 1-10 Purkinje neurons.

—Eric R. Kandel et al., Principles of Neural Science, 4th Edition, 2000

Word History

First Known Use

1950, in the meaning defined above

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