The Motor Pathway
The corticospinal tract originates from pyramidal cells in layer V of the cerebral cortex. About half of its fibres arise from the primary motor cortex. Other contributions come from the supplementary motor area, premotor cortex, somatosensory cortex, parietal lobe, and cingulate gyrus. The average fiber diameter is in the region of 10μm; around 3% of fibres are extra-large (20μm) and arise from Betz cells, mostly in the leg area of the primary motor cortex.
Read more about this topic: Pyramidal Tracts
Famous quotes containing the words motor and/or pathway:
“This biplane is the shape of human flight.
Its name might better be First Motor Kite.”
—Robert Frost (1874–1963)
“And open field, through which the pathway wound,
And homeward led my steps. Magnificent
The morning rose, in memorable pomp,
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The solid mountains shone, bright as the clouds,
Grain-tinctured, drenched in empyrean light;”
—William Wordsworth (1770–1850)