Lateral corticospinal tract

Lateral corticospinal tract
Lateral corticospinal tract labeled in red at upper left.
Latin	tractus corticospinalis lateralis, fasciculus cerebrospinalis lateralis
Gray's	subject #185 759

The lateral corticospinal tract (also called the crossed pyramidal tract or lateral cerebrospinal fasciculus) is the largest part of the corticospinal tract. It extends throughout the entire length of the medulla spinalis, and on transverse section appears as an oval area in front of the posterior column and medial to the posterior spinocerebellar tract.

Its fibres arise from cells in the motor area of the cerebral hemisphere of the opposite side.

They pass downward in company with those of the anterior corticospinal tract through the same side of the brain as that from which they originate, but they cross to the opposite side in the medulla oblongata and descend in the lateral funiculus of the medulla spinalis.

The lateral corticospinal tract controls movement of ipsilateral limbs(albeit contralateral to the corresponding motor cortex) as it lies distal to the pyramidal decussation. Control of more central axial and girdle muscles comes from the anterior corticospinal tract.

Additional images

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  Decussation of pyramids.

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  Section of the medulla oblongata through the lower part of the decussation of the pyramids

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  Section of the medulla oblongata at the level of the decussation of the pyramids.

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  The motor tract.

External links

• NeuroNames hier-798
• -845545463 at GPnotebook
• Lateral+corticospinal+tract at eMedicine Dictionary
• Overview at thebrain.mcgill.ca
• Neuroanatomy at UW sc97/text/P4/intro.htm

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.