Rubrospinal tract
Rubrospinal tract | |
---|---|
Details | |
Identifiers | |
Latin | tractus rubrospinalis |
NeuroLex ID | birnlex_1476 |
TA98 | A14.1.02.220 A14.1.04.136 A14.1.05.332 A14.1.06.213 |
TA2 | 6097 |
FMA | 73995 |
Anatomical terminology |
This article needs additional citations for verification. (October 2011) |
The rubrospinal tract is a descending tract of the spinal cord connecting to the red nucleus. It is a part of the lateral indirect extrapyramidal tract.
It is rudimentary[1]: 114 and functionally less important in humans.[1]: 244 It is involved in motor control of distal flexors of the upper limb - especially of the hand and fingers[1]: 114 - by promoting flexor tone while inhibiting extensors.[1]: 242 It complements the lateral corticospinal tract.[1]: 298
Anatomy
[edit]The rubrospinal tract originates in the magnocellular red nucleus[1]: 114 in the caudal part of the red nucleus of the midbrain. It decussates (crosses over) within the anterior tegmentum of the midbrain.[1]: 241 In the pons, it is situated medially within the rostral pontine tegmentum.[1]: 109 In the medulla oblongata, it descends within the lateral tegmentum medial to the spinocerebellar tract, and posterior to the spinothalamic tract.[1]: 100 In the spinal cord, it descends in the lateral funiculus,[1]: 241 adjacent to the lateral corticospinal tract.[citation needed] It terminates in the contralateral cervical spinal cord[1]: 297 by synapsing with interneurons of the lateral intermediate zone and anterior horn of the spinal cord.[1]: 241
Function
[edit]In humans, the rubrospinal tract is one of several major motor control pathways. It is smaller and has fewer axons than the corticospinal tract, suggesting that it is less important in motor control. It is one of the pathways for the mediation of involuntary movement, along with other extra-pyramidal tracts including the vestibulospinal, tectospinal, and reticulospinal tracts. The tract is responsible for large muscle movement regulation flexor and inhibiting extensor tone as well as fine motor control.[2] It terminates primarily in the cervical and thoracic portions of the spinal cord, suggesting that it functions in upper limb but not in lower limb control.
It is small and rudimentary in humans. In some other primates, however, experiments have shown that over time, the rubrospinal tract can assume almost all the duties of the corticospinal tract when the corticospinal tract is lesioned.[citation needed]
See also
[edit]References
[edit]- ^ a b c d e f g h i j k l Patestas, Maria A.; Gartner, Leslie P. (2016). A Textbook of Neuroanatomy (2nd ed.). Hoboken, New Jersey: Wiley-Blackwell. ISBN 978-1-118-67746-9.
- ^ "Spinal Reflexes and Descending Motor Pathways (Section 3, Chapter 2) Neuroscience Online: An Electronic Textbook for the Neurosciences | Department of Neurobiology and Anatomy - the University of Texas Medical School at Houston". Archived from the original on 2011-12-27. Retrieved 2012-01-03.