Tractus corticospinalis lateralis

Tractus corticospinalis lateralis

The Tractus corticospinalis lateralis, also known as the lateral corticospinal tract, is a major descending pathway in the central nervous system. It plays a crucial role in the voluntary control of movement.

Anatomy

The tract originates from the primary motor cortex in the precentral gyrus of the cerebral cortex. The axons of the pyramidal cells in this region form the corticospinal tract, which descends through the internal capsule and the cerebral peduncle of the midbrain. As it descends, the tract crosses over to the opposite side of the brain at the level of the pyramidal decussation in the medulla oblongata. After crossing over, the tract continues its descent in the lateral funiculus of the spinal cord, giving rise to its name, the lateral corticospinal tract.

Function

The main function of the lateral corticospinal tract is to transmit voluntary motor commands from the cerebral cortex to the skeletal muscles of the body. These commands are responsible for initiating and controlling precise movements, such as fine motor skills and skilled movements. The tract carries signals that control both distal (e.g., hands and feet) and proximal (e.g., shoulder and hip) muscles.

Clinical Significance

Damage to the lateral corticospinal tract can result in spastic paralysis, a condition characterized by increased muscle tone and exaggerated reflexes. This condition occurs due to the loss of inhibitory control from the cerebral cortex over the spinal cord. Common causes of damage to the tract include stroke, traumatic brain injury, and neurodegenerative diseases.

See Also

• Corticospinal tract
• Pyramidal decussation
• Motor cortex
• Internal capsule
• Cerebral peduncle
• Medulla oblongata
• Spinal cord