Oculomotor nucleus

Oculomotor nucleus
Brain: Oculomotor nucleus
Cn3nucleus.png
Section through superior colliculus showing path of oculomotor nerve.
Gray696.svg
The cranial nerve nuclei schematically represented; dorsal view. Motor nuclei in red; sensory in blue. (Oculomotor is "III")
Latin nucleus nervi oculomotorii
Gray's subject #188 807
NeuroNames hier-483

The fibers of the oculomotor nerve arise from a nucleus in the midbrain, which lies in the gray substance of the floor of the cerebral aqueduct and extends in front of the aqueduct for a short distance into the floor of the third ventricle. From this nucleus the fibers pass forward through the tegmentum, the red nucleus, and the medial part of the substantia nigra, forming a series of curves with a lateral convexity, and emerge from the oculomotor sulcus on the medial side of the cerebral peduncle.

The nucleus of the oculomotor nerve does not consist of a continuous column of cells, but is broken up into a number of smaller nuclei, which are arranged in two groups, anterior and posterior. Those of the posterior group are six in number, five of which are symmetrical on the two sides of the middle line, while the sixth is centrally placed and is common to the nerves of both sides. The anterior group consists of two nuclei, an antero-medial and an antero-lateral .

The nucleus of the oculomotor nerve, considered from a physiological standpoint, can be subdivided into several smaller groups of cells, each group controlling a particular muscle.

A nearby nucleus, the Edinger-Westphal nucleus, is responsible for the autonomic functions of the oculomotor nerve, including pupillary constriction and lens accommodation.

Additional images

  • Nuclei of origin of cranial motor nerves schematically represented; lateral view.

  • Coronal section through mid-brain.

  • Transverse section of mid-brain at level of inferior colliculi.

  • Scheme showing central connections of the optic nerves and optic tracts.

  • Plan of oculomotor nerve.

  • Figure showing the mode of innervation of the Recti medialis and lateralis of the eye.

External links

v · d · eHuman brain: mesencephalon (midbrain) (TA A14.1.06, GA 9.800)
Tectum
(Dorsal)
Surface
White: Sensory/ascending
White: Motor/descending
Peduncle
(Ventral)
White: Sensory/ascending
lemnisci (Medial, Lateral) · Ascending MLF (Vestibulo-oculomotor fibers) · Spinothalamic tract · Anterior trigeminothalamic tract · Dentatothalamic tract
White: Motor/descending
Grey: other
Base
White: Motor/descending
Surface

M: CNS

anat(n/s/m/p/4/e/b/d/c/a/f/l/g)/phys/devp

noco(m/d/e/h/v/s)/cong/tumr, sysi/epon, injr

proc, drug(N1A/2AB/C/3/4/7A/B/C/D)
v · d · eNerves of head and neck: the cranial nerves and nuclei (TA A14.2.01, GA 9.855)
olfactory (AON->I)
optic (LGN->II)
oculomotor
(ON, EWN->III)
trochlear (TN->IV)
no significant branches
trigeminal
(PSN, TSN, MN, TMN->V)
abducens (AN->VI)
no significant branches
facial (FMN, SN, SSN->VII)
near origin
vestibulocochlear
(VN, CN->VIII)
glossopharyngeal
(NA, ISN, SN->IX)
ganglia (superior, inferior)
vagus
(NA, DNVN, SN->X)
ganglia (superior, inferior)
accessory (NA, SAN->XI)
hypoglossal (HN->XII)

M: PNS

anat(h/r/t/c/b/l/s/a)/phys(r)/devp/prot/nttr/nttm/ntrp

noco/auto/cong/tumr, sysi/epon, injr

proc, drug(N1B)
v · d · eSensory system: Visual system and eye movement pathways
Visual perception
1° (Bipolar cell of Retina) → 2° (Ganglionic cell) → 3° (Optic nerve → Optic chiasm → Optic tract → LGN of Thalamus) → 4° (Optic radiation → Cuneus and Lingual gyrus of Visual cortex → Blobs → Globs)
Muscles of orbit
Tracking
Horizontal gaze
PPRF → Abducens nucleus → MLF → Oculomotor nucleus → Medial rectus muscle
Vertical gaze
Pupillary reflex
Pupillary dilation
Circadian rhythm

M: EYE

anat(g/a/p)/phys/devp/prot

noco/cong/tumr, epon

proc, drug(S1A/1E/1F/1L)

Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • oculomotor nucleus — n a nucleus that is situated under the aqueduct of Sylvius rostral to the trochlear nucleus and is the source of the motor fibers of the oculomotor nerve * * * nucleus of oculomotor nerve n. nervi oculomotorii …   Medical dictionary

  • Oculomotor nerve — Nerve: Oculomotor nerve Nerves of the orbit. Seen from above …   Wikipedia

  • nucleus nervi oculomotorii — [TA] nucleus of oculomotor nerve: a nuclear complex that is the origin of the fibers of the oculomotor nerve, situated in the tegmentum of the mesencephalon immediately ventral to the central gray matter, between the medial longitudinal fasciculi …   Medical dictionary

  • nucleus commissurae posterioris — [TA] nucleus of posterior commissure: a nucleus of the rostral midbrain tegmentum, located adjacent to the posterior commissure and near the oculomotor nucleus …   Medical dictionary

  • oculomotor nuclear complex — nucleus nervi oculomotorius …   Medical dictionary

  • Nucleus — 1) In cell biology, the structure that houses the chromosomes. 2) In neuroanatomy, a group of nerve cells. * * * 1. In cytology, typically a rounded or oval mass of protoplasm within the cytoplasm of a plant or animal cell; it is surrounded by a… …   Medical dictionary

  • nucleus anteromedialis nervi oculomotorii — [TA] anterior medial nucleus of oculomotor nerve: ventrally placed cells in the lateral part of the oculomotor nuclear complex (nucleus nervi oculomotorii); they are distinct from the dorsally placed cells in the middle third of the complex and… …   Medical dictionary

  • nucleus dorsalis nervi oculomotorii — [TA] dorsal nucleus of oculomotor nerve: a group of dorsally placed cells in the lateral part of the oculomotor nuclear complex (nucleus nervi oculomotorii); they are distinct from the ventrally placed cells in the middle third of the complex and …   Medical dictionary

  • Nucleus ambiguus — Brain: Nucleus ambiguus Transverse section of medulla oblongata below the middle of the olive. ( Nucleus ambiguus labeled at center right.) Gray s subject #187 …   Wikipedia

  • nucleus caudalis centralis — central caudal nucleus: an unpaired collection of cells in the caudal third of the oculomotor nuclear complex (nucleus nervi oculomotorii [TA]), located in the median raphe somewhat dorsal to the lateral nuclei …   Medical dictionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”