Question

Explain the corticospinal, corticobulbar, dorsal columns, spinothalamic, vestibulospinal, tectospinal, rubrospinal and spinocerebellar tracts in your own words, approx. 1-2 paragraphs per tract.

Answer 1

Corticospinal tract:-

It is a white matter motor pathway.Starting at the cerebral cortex that terminates on lower motor neurons and interneurons in the spinal cord,controlling movement of the limbs and trunk.

Corticobulbar(or corticonuclear ) tract:-

It is a two-neuron white matter motor pathway connecting the motor cortex in the cerebral cortex to medullary pyramids,which are part of the brain stems medulla oblongata (also called bulbar) region and are primarily involved in carrying the motor function of the non oculomotor central nervous system.

Dorsal column tract:-

Dorsal column medial lemniscus pathway (DCML) (also known as the posterior column medial lemniscus pathway (PCML)) is a sensory pathway of the CNS that conveys sensation of the fine touch vibration,two point discrimination and proprioception (position)from the skin and joints.

Spinothalamic tract :-(part of the anteriolateral system or ventrolateral system) -

It is a sensory pathway to the thalamus from the ventral posterolateral nucleus in the thalamus sensory information is relayed upward to the somatosensory cortex of the post central gyrus.

Vestibulospinal tract:- these are the descending tracts that originate from the vestibular nuclei of brain stem.They consist of a medial tract and lateral tract.The medial vestibulospinal tract arises from the medial vestibular nucleus.

Tectospinal tract :-

In the human the tectospinal tract (or colliculospinal tract ) is a nerve tract that co-ordinate head and eye movements.This tract is part of the extra pyramidal system and connect the mid brain tectum and cervical region of the spinal cord.

Rubrospinal tract:-

​​​​​​It is a descending tract in the spinal cord essential for controlling motor activity.It is present in the lateral gray column of spinal cord ,one in each half.The Ist order neurons are present in the red nucleus and central cortex.

Spinocerebellar tract:-

It is a nerve tract from the spinal cord and terminating in the same side of cerebellum.The spinocerebellar tracts occupy the periphery of the lateral funiculus and carry proprioceptive and cutaneous information from Golgi tendon organ and muscle spindle to the cerebellum for co-ordination of movements.