Cuneate fasciculus


Cuneate fasciculus
Fasciculus cuneatus
Spinal cord tracts - English.svg
Cuneate fasciculus is labeled in blue at upper right.
Gray672.png
Diagram of the principal fasciculi of the spinal cord.
Latin fasciculus cuneatus medullae spinalis
Gray's subject #185 763

The fasciculus cuneatus (tract of Burdach, named for Karl Friedrich Burdach) is a tract of nerves in the spinal cord which primarily transmits information from the arms. It is part of the posterior column-medial lemniscus pathway.

Contents

Physical characteristics

The fasciculus cuneatus is triangular on transverse section, and lies between the fasciculus gracilis and the posterior column, its base corresponding with the surface of the medulla spinalis.

Its fibers, larger than those of the fasciculus gracilis, are mostly derived from the same source, viz., the posterior nerve roots.

Some ascend for only a short distance in the tract, and, entering the gray matter, come into close relationship with the cells of the dorsal nucleus; while others can be traced as far as the medulla oblongata, where they end in the gracile nucleus and cuneate nucleus.

Function

The Fasciculus cuneatus transmits fine touch, fine pressure, vibration and proprioception information from spinal nerves located in dermatomes C1 through T6.

Neurons

The Fasciculus cuneatus tract is composed of 1st order neurons that synapse onto 2nd order neurons in the brain stem.

The 2nd order neurons decussate in the brainstem and continue on to the thalamus where the 2nd order neurons synapse onto 3rd order neurons.

The 3rd order neurons carry the received signals to the somatosensory cortex where the signals, in the form of action potentials are interpreted.

Additional images

Decussation of pyramids.
Superficial dissection of brain-stem. Lateral view.
The sensory tract.
Superior terminations of the posterior fasciculi of the medulla spinalis.
Upper part of medulla spinalis and hind- and mid-brains; posterior aspect, exposed in situ.


See also

External links



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Look at other dictionaries:

  • cuneate fasciculus — n, pl cuneate fasciculi FASCICULUS CUNEATUS …   Medical dictionary

  • cuneate fasciculus of medulla oblongata — f. cuneatus medullae oblongatae …   Medical dictionary

  • cuneate fasciculus of spinal cord — f. cuneatus medullae spinalis …   Medical dictionary

  • Cuneate — means wedge shaped, it can apply to: cuneate leaf, a leaf shape the cuneate nucleus, a part of the brainstem the cuneate fasciculus, a tract from the spinal cord into the brainstem This disambiguation page lists articles associated with the same… …   Wikipedia

  • fasciculus cuneatus — fasciculus cu·ne·atus .kyü nē āt əs n either of a pair of nerve tracts of the posterior funiculus of the spinal cord that are situated on opposite sides of the posterior median septum lateral to the fasciculus gracilis and that carry nerve fibers …   Medical dictionary

  • Cuneate nucleus — Brain: Cuneate nucleus Dissection of brain stem. Dorsal view. (Label for nucleus cuneatus is on left, third from the bottom.) …   Wikipedia

  • fasciculus cuneatus medullae spinalis — [TA] cuneate fasciculus of spinal cord: the lateral portion of the posterior funiculus of the spinal cord, composed of ascending fibers that terminate in the nucleus cuneatus of the medulla oblongata; called also Burdach f. Fasciculus cuneatus… …   Medical dictionary

  • fasciculus cuneatus medullae oblongatae — [TA] cuneate fasciculus of medulla oblongata: the continuation into the medulla oblongata of the fasciculus cuneatus of the spinal cord …   Medical dictionary

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  • Fasciculus cuneatus — Infobox Anatomy Name = Fasciculus cuneatus Latin = fasciculus cuneatus medullae spinalis GraySubject = 185 GrayPage = 763 Caption = Fasciculus cuneatus is 3b, in blue at upper right. Caption2 = Diagram of the principal fasciculi of the spinal… …   Wikipedia