Medullary pyramid - Medullary pyramid

Japanese: 延髄錐体 - えんずいすいたい

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[Pyramidal tract movement disorder]
The axons of the giant pyramidal cells of Betz, which are nerve cells in the motor cortex of the cerebral cortex, reach motor neurons in the brainstem and spinal cord and connect with them through synapses. Some of these axons that reach the spinal cord pass through the medullary pyramid, and are therefore called pyramidal tracts. This system is active in voluntary movements, especially when performing quick, skillful movements using willpower, to regulate movement.

From [medulla oblongata]

The anterior medullary funiculus is made up of the pyramidal tract, which is a nerve tract that connects the olivary nucleus to the brain.
[Internal structure]
Within the medulla oblongata are nuclei (groups of nerve cells or neurons) that perform various functions and tracts that pass through or connect to the nuclei.

*Some of the terminology that refers to the "medullary pyramid" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

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［錐体路系の運動障害］
　大脳皮質運動野にある神経細胞であるベッツ巨大錐体細胞から出た軸索は，脳幹や脊髄の運動ニューロンに達して，シナプスで連絡する。これらの軸索のうち脊髄にまで達するものは延髄錐体medullary pyramidを通るため錐体路pyramidal tractと呼ばれる。この系統は，随意運動，とくに意志の力によるすばやい巧みな運動を行う際に作動して運動を調節する。…