The corticospinal tract, also known as the pyramidal tract, is a major pathway of the central nervous system which conveys motor information from the cerebral cortex to the lower motor neurons in the brainstem and spinal cord. It is composed of axons from upper motor neurons (UMNs) located in the primary motor cortex, the premotor cortex, the supplementary motor area, and the cingulate motor area (Girgis et al., 2016). The corticospinal tract is one of the most important motor pathways in the body, playing a vital role in motor control, coordination, and movement.
The axons of UMNs in the corticospinal tract travel from the cortex through the internal capsule and the cerebral peduncles of the midbrain before decussating (crossing over) at the pyramids of the medulla oblongata (Girgis et al., 2016). Once crossed, the axons travel down the spinal cord, synapsing with lower motor neurons (LMNs) along the way. LMNs are located in the ventral horn of the spinal cord and are responsible for controlling the contraction of the skeletal muscles (Girgis et al., 2016). Thus, the corticospinal tract is responsible for conveying motor information from the cortex to the LMNs, which results in the execution of voluntary movements.
The corticospinal tract is not the only motor pathway in the central nervous system. Other motor pathways include the rubrospinal tract, the reticulospinal tract, and the vestibulospinal tract (Girgis et al., 2016). The rubrospinal tract originates from the red nucleus in the midbrain and descends through the midbrain and the spinal cord, synapsing with LMNs along the way. The reticulospinal tract is a pathway of both motor and autonomic neurons that originates from the reticular formation of the brainstem. The vestibulospinal tract is responsible for conveying information from the vestibular system, which is responsible for maintaining balance and postural control.
The corticospinal tract is an important motor pathway of the central nervous system, responsible for conveying motor information from the primary motor cortex to the lower motor neurons in the brainstem and spinal cord. It is composed of axons from UMNs located in various regions of the cortex, which travel through the internal capsule, the cerebral peduncles, and the pyramids of the medulla before decussating at the pyramids and synapsing with LMNs located in the ventral horns of the spinal cord. It is one of several motor pathways of the CNS, including the rubrospinal tract, the reticulospinal tract, and the vestibulospinal tract.
References
Girgis, F. F., Abouleish, A. E., & Karlin, J. E. (2016). Neuroanatomy: An illustrated color text. Philadelphia, PA: Elsevier.