from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Either of the sixth pair of cranial nerves that convey motor impulses to the rectus muscle on the lateral side of each eye.
from the GNU version of the Collaborative International Dictionary of English
- n. a small motor nerve supplying the lateral rectus muscle of the eye.
from The Century Dictionary and Cyclopedia
- n. In anatomy, one of the sixth pair of cranial nerves: so called because it is the motor nerve of the rectus externus (external straight) muscle of the eye, which turns the eyeball outward.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a small motor nerve supplying the lateral rectus muscle of the eye
From the ventral longitudinal bundle collaterals are given off to the nuclei of the eye muscles, the oculomotor, the trochlear and the abducens.
Since oculomotor and abducens nuclei are intimately connected by the posterior longitudinal bundle this decussation of fibers to the Medial rectus may facilitate the conjugate movements of the eyes in which the Medial and Lateral recti are especially involved.
The fibers arise from the nucleus of the abducens nerve and pass ventrally through the formatio reticularis of the pons to emerge in the transverse groove between the caudal edge of the pons and the pyramid.
Its axons pass into the posterior longitudinal bundle of the same and the opposite side and ascend to terminate in the nucleus abducens of the same side and in the trochlear nucleus and the oculo-motor nucleus of the opposite side, and to the motor nuclei of the trigeminal on both sides.
Many collaterals and terminals are given off to the oculomotor nucleus from the posterior longitudinal bundle and thus connect it with the vestibular nucleus, the trochlear and abducens nuclei and probably with other cranial nuclei.
The abducens nucleus probably receives collaterals and terminals from the ventral longitudinal bundle (tectospinal fasciculus); fibers which have their origin in the superior colliculus, the primary visual center, and are concerned with visual reflexes.
The olfactory, optic, oculo-motor, pathetic, ophthalmic division of the trigeminal, and the abducens nerves are all liable to be implicated.
She developed acute bilateral abducens neuropathy with post-tetanic facilitation alongside acute laryngopharyngodysesthesia and hypokalemia.
For example, the abducens and facial nuclei appear at the level of the caudal pons.
The axons bifurcate as they enter the posterior longitudinal bundle, the ascending branches send terminals and collaterals to the motor nuclei of the abducens, trochlear and oculomotor nerves, and are concerned in coördinating the movements of the eyes with alterations in the position of the head; the descending branches pass down in the posterior longitudinal bundle into the anterior funiculus of the spinal cord as the vestibulospinal fasciculus (anterior marginal bundle) and are distributed to motor nuclei of the anterior column by terminals and collaterals.
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