Posterior external arcuate fibers
Encyclopedia
The posterior external arcuate fibers (dorsal external arcuate fibers) take origin in the gracile
and cuneate
nuclei; they pass to the inferior peduncle of the same side.
It is uncertain whether fibers are continued directly from the gracile and cuneate fasciculi into the inferior peduncle.
The term "cuneocerebellar tract" is sometimes used to collectively refer to the posterior external arcuate fibers.
The term "cuneocerebellar tract" is also used to describe an analogue to the dorsal spinocerebellar tract
for the upper limb
s. In this context, the "cuneo-" derives from the accessory cuneate nucleus
, not the cuneate nucleus
. (The two nuclei are related in space, but not in function.)
Gracile nucleus
Located in the medulla oblongata, the gracile nucleus is one of the dorsal column nuclei that participate in the sensation of fine touch and proprioception of the lower body...
and cuneate
Cuneate nucleus
One of the dorsal column nuclei, the cuneate nucleus is a wedge-shaped nucleus in the closed part of the medulla oblongata. It contains cells that give rise to the cuneate tubercle, visible on the posterior aspect of the medulla...
nuclei; they pass to the inferior peduncle of the same side.
It is uncertain whether fibers are continued directly from the gracile and cuneate fasciculi into the inferior peduncle.
The term "cuneocerebellar tract" is sometimes used to collectively refer to the posterior external arcuate fibers.
The term "cuneocerebellar tract" is also used to describe an analogue to the dorsal spinocerebellar tract
Dorsal spinocerebellar tract
The dorsal spinocerebellar tract conveys inconscient proprioceptive information from the body to the cerebellum....
for the upper limb
Upper limb
The upper limb or upper extremity is the region in an animal extending from the deltoid region to the hand, including the arm, axilla and shoulder.-Definition:...
s. In this context, the "cuneo-" derives from the accessory cuneate nucleus
Accessory cuneate nucleus
The accessory cuneate nucleus is located lateral to the cuneate nucleus in the medulla oblongata at the level of the sensory decussation ....
, not the cuneate nucleus
Cuneate nucleus
One of the dorsal column nuclei, the cuneate nucleus is a wedge-shaped nucleus in the closed part of the medulla oblongata. It contains cells that give rise to the cuneate tubercle, visible on the posterior aspect of the medulla...
. (The two nuclei are related in space, but not in function.)