Medial lemniscus
| Medial lemniscus | |
|---|---|
 The sensory tract. (Medial lemniscus labeled at top right.) | |
 Coronal section through mid-brain. ("e" is Portion of medial lemniscus, which runs to the lentiform nucleus and insula. "a’" is also the medial lemniscus.) | |
| Details | |
| Identifiers | |
| Latin | lemniscus medialis |
| NeuroLex ID | birnlex_887 |
| TA98 | A14.1.04.111 A14.1.08.672 A14.1.06.207 |
| TA2 | 5861 |
| FMA | 83675 |
| Anatomical terms of neuroanatomy | |
In neuroanatomy, the medial lemniscus (also known as Reil's band or Reil's ribbon (for German anatomist Johann Christian Reil) is a large ascending bundle of heavily myelinated[citation needed] decussating (crossing-over) second-order axons that extends throughout the brainstem. It represents the decussation of the internal arcuate fibers (which originate in the nucleus gracilis and nucleus cuneatus). The medial lemniscus is part of the dorsal column–medial lemniscus pathway that conveys information from skin mechanoreceptors to the thalamus.[1] Lesion of the medial lemnisci cause impairment of vibratory and touch sensation.[citation needed]
Anatomy
[edit]Structure
[edit]In the medulla oblongata, axons conveying stimuli from the lower body are situated ventrally/anteriorly, and those of the upper body dorsally/posteriorly. Passing through the pons and midbrain, the axons of the lemniscus rotate laterally by 90° so that those of the upper body come to be situated medially, and those of the lower body laterally.[1]
Course/relations
[edit]In the midbrain, it is situated dorsal/posterior to the substantia nigra, and medial to either red nucleus.[2]
It terminates by synapsing with third-order neurons in the ventral posterolateral nucleus of thalamus.[1][2]
See also
[edit]Additional images
[edit]-
Deep dissection of brain-stem. Lateral view. -
Deep dissection of brain-stem. Ventral view. -
Coronal section of the pons, at its upper part. -
Transverse section of mid-brain at level of inferior colliculi. -
Scheme showing the course of the fibers of the lemniscus; medial lemniscus in blue, lateral in red. -
Horizontal section through the lower part of the pons. The medial lemniscus is labeled #17. -
Tractography showing medial lemniscus
References
[edit]- ^ a b c Purves, Dale, ed. (2018). Neuroscience (6th ed.). New York: Oxford University Press. pp. 202–204. ISBN 978-1-60535-380-7.
- ^ a b "medial lemniscus - Dictionnaire médical de l'Académie de Médecine". www.academie-medecine.fr. Retrieved 2024-07-27.
