Purkinje layer of cerebellar cortex
anywhere else???
fan-like dendritic arborization (extend into molecular cell layer)
a single one of the climbing fibers - v powerful excitatory effect -> complex spike
parallel fibers -> simple spike
requires spatial and temporal summation of inputs from several parallel fibers before firing
same for cerebellar mossy fibers???
a million granule cells
inhibited by
inhibitory
project topographically to deep cerebellar nuclei
underlying white matter
large cell bodies
Purkinje cells ' dendritic arborizations extend upward into molecular layer
up to 100 spikes/second
frequency
represents magnitude and duration of peripheral stimuli or centrally generated behaviors
e.g. somatosensory, vestibular
also driven by voluntary eye or limb movements
regulate how much
the cerebellar mossy fibers and climbing fibers activate the deep nuclei
the cerebellum influences the motor system
input from 100-200,000 parallel fibers
excitatory input from inferior olivary nucleus via a single climbing fiber
spiking
wikipedia says:
simple spikes - the parllel fibers are supposed to be responsible for the all-or-nothing amplitude-invariant spiking
complex spikes - excitatory postsynaptic response of Purkinje cells from climbing fibers are amplitude-invariant
primary integrative cerebellar cortex neurons
sole output of cerebellar cortex
large dendrites with hundreds of spiny branches into molecular layer
mostly all flat (lie in planes) with neighboring Purkinje arbors in parallel plns
each parallel fiber from the granule cells runs orthogonally