Tract Types of Spinal Cord

Dorsal Spinocerebellar tract: The fibers of this tract arise from the cells of the nucleus dorsalis (N.D.: the well defined collection of cells occupying, the inner part of the base of the dorsal horn is known as Clark’s column; this group is confined almost entirely to the thoracic region of the cord is also known as the dorsal nucleus) on the same side and pass to the cerebellum by way of the inferior peduncle. The tract conveys proprioceptive impulses from muscles and tendons of the limbs. The velocity of the nerve impulses conducted in this tract is high. The tract is found in the drsolatera1 part of the lateral funiculus.

Ventral Spinocerebellar tract

The fibers of this tract Originate from nerve cells in the dorsal column, on the same and opposite sides, and enter the cerebellum by way of the superior peduncle. It conveys proprioceptive impulses from the trunk musculature. It is found in the ventro-lateral part of the lateteral funiculus.

Lateral Spinothalamic tract
Consists of fibers that originate from nerve cells in the dorsal column of the opposite side and run in the lateral funiculus. The tract ends in the thalamus. From nerve cells in these organ axons arise and pass to the cerebral cortex.

The spino-thalamic tracts conduct nerve impulses which mediate the following kinds of sensation: Pressure and touch (in part), cutaneous, muscular and visceral regions, warmth and cold, cutaneous tickle, itch, muscular fatigue, bladder and sexual sensations.

These are the motor tracts. They connect the different parts of the brain with the spinal cord. Some of them originate in the cerebral cortex, whereas others originate at various reflex centers in the brain stem.

Corticospinal tracts of man

These are the most important descending Tracts in man. Constituting the only direct motor connection between the cerebral cortex and the spinal cord they place the motoneurons and thus the skeletal muscles, under cerebral control. There are two corticospinal tracts: Lateral and ventral on each side.

The lateral cortico spinal tract known also as the crossed pyramidal, is located in the lateral funiculus. It is composed of fibers that originate on the opposite side of the cerebral cortex and cross the median plane in the decussation of the pyramids at the lower border of the medulla oblongata.

Rubro-spinal tract
this tract sends some of its fibers back as far as the sal region. Its fibers originate from the red nucleus of the midbrain, 8fld immediately after leaving the nucleus they cross the medial plane they end either directly or through internuncial neurons in synaptic relation with the motoneurons of the ventral column. The fibers of the rubrospinal tract convey impulses from the cerebellum and corpus striatum to the motoneurons. This tract is not well developed in man.