Posterior root of spinal nerve
|Posterior root of spinal nerve|
The formation of the spinal nerve from the dorsal and ventral roots
The posterior root (or dorsal root) is one of two "roots" which emerge from the spinal cord. It emerges directly from the spinal cord, and travels to the posterior root ganglion. Nerve fibres with the anterior root then combine to form a spinal nerve. The posterior root transmits sensory information, forming the afferent sensory root of a spinal nerve.
The lateral division of the posterior root contains lightly myelinated and unmyelinated fibres of small diameter. These carry pain and temperature sensation. These fibers cross through the anterior white commissure to form the anterolateral system in the lateral funiculus.
The medial division of the dorsal root contains myelinated fibres of larger diameter. These transmit information of discriminative touch, pressure, vibration, and conscious proprioception originating from spinal levels C2 through S5. These fibers are pushed in towards the posterior median sulcus to form the gracile fasciculus and the cuneate fasciculus.
If the posterior root of a spinal nerve were severed it would lead to numbness in certain areas of the body.
- Anatomy figure: 02:04-06 at Human Anatomy Online, SUNY Downstate Medical Center - "Superior view of a section through the spinal cord within the vertebral foramen."
- Anatomy Atlases - Microscopic Anatomy, plate 06.114 - "Spinal Root Nerve Fibers"
- Dorsal Root - Cell Centered Database
|This neuroscience article is a stub. You can help Wikipedia by expanding it.|