A report on Nucleus ambiguus

Transverse section of medulla oblongata below the middle of the olive. ("Nucleus ambiguus" labeled at center right.)
Section of the medulla oblongata at about the middle of the olive.
The cranial nerve nuclei schematically represented; dorsal view. Motor nuclei in red; sensory in blue.
Nuclei of origin of cranial motor nerves schematically represented; lateral view.
The formatio reticularis of the medulla oblongata, shown by a transverse section passing through the middle of the olive.

Group of large motor neurons, situated deep in the medullary reticular formation named by Jacob Clarke.

- Nucleus ambiguus
Transverse section of medulla oblongata below the middle of the olive. ("Nucleus ambiguus" labeled at center right.)

6 related topics with Alpha

Overall

Plan of the upper portions of the glossopharyngeal, vagus, and accessory nerves.

Vagus nerve

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Cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract.

Cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract.

Plan of the upper portions of the glossopharyngeal, vagus, and accessory nerves.
H&E stained fibers of the vagus nerve (bottom right) innervate the sinoatrial node tissue (middle left)
Inferior view of the human brain, with the cranial nerves labeled.
Section of the neck at about the level of the sixth cervical vertebra
Transverse section of thorax, showing relations of pulmonary artery
The arch of the aorta, and its branches
Dura mater and its processes exposed by removing part of the right half of the skull, and the brain
The tracheobronchial lymph glands
Section of the medulla oblongata at about the middle of the olive
Hind- and mid-brains; postero-lateral view
Upper part of medulla spinalis and hind- and mid-brains; posterior aspect, exposed in situ
The right sympathetic chain and its connections with the thoracic, abdominal, and pelvic plexuses
The celiac ganglia with the sympathetic plexuses of the abdominal viscera radiating from the ganglia
The position and relation of the esophagus in the cervical region and in the posterior mediastinum, seen from behind
The thyroid gland and its relations
The thymus of a full-term fetus, exposed in situ
Deep dissection of vagus nerve
Vagus nerve – dissection

The sensory fibers originate from neurons of the nodose ganglion, whereas the motor fibers come from neurons of the dorsal motor nucleus of the vagus and the nucleus ambiguus.

Medulla oblongata purple, part of the brain stem colored

Medulla oblongata

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Long stem-like structure which makes up the lower part of the brainstem.

Long stem-like structure which makes up the lower part of the brainstem.

Medulla oblongata purple, part of the brain stem colored
Medulla oblongata (animation)
Medulla and parts (10-16) - (10) pyramid; (11) the anterior median fissure; (15) is the choroid plexus in the fourth ventricle; (13) olive and (7) the pons
Medulla-animated as it protrudes from the foramen magnum of the skull-base, after which it gives rise to the spinal cord.
Lobes
Cross section of the medulla (in red) and surrounding tissues.
Anteroinferior view of the medulla oblongata and pons.
Base of brain.
Diagram showing the positions of the three principal subarachnoid cisternæ.
Medulla oblongata
Micrograph of the posterior portion of the open part of the medulla oblongata, showing the fourth ventricle (top of image) and the nuclei of CN XII (medial) and CN X (lateral). H&E-LFB stain.

The nucleus ambiguus, which form the special visceral efferent.

Corticobulbar tract.

Corticobulbar tract

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Two-neuron white matter motor pathway connecting the motor cortex in the cerebral cortex to the medullary pyramids, which are part of the brainstem's medulla oblongata (also called "bulbar") region, and are primarily involved in carrying the motor function of the non-oculomotor cranial nerves.

Two-neuron white matter motor pathway connecting the motor cortex in the cerebral cortex to the medullary pyramids, which are part of the brainstem's medulla oblongata (also called "bulbar") region, and are primarily involved in carrying the motor function of the non-oculomotor cranial nerves.

Corticobulbar tract.

The corticobulbar tract also contributes to the motor regions of cranial nerve X in the nucleus ambiguus.

Nuclei of origin of cranial motor nerves schematically represented; lateral view. ("X" visible at bottom center.)

Dorsal nucleus of vagus nerve

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Cranial nerve nucleus for the vagus nerve in the medulla that lies ventral to the floor of the fourth ventricle.

Cranial nerve nucleus for the vagus nerve in the medulla that lies ventral to the floor of the fourth ventricle.

Nuclei of origin of cranial motor nerves schematically represented; lateral view. ("X" visible at bottom center.)
Section of the medulla oblongata at about the middle of the olive.
The cranial nerve nuclei schematically represented; dorsal view. Motor nuclei in red; sensory in blue.
Dorsal motor nucleus of Vagus with Lewy body pathology

The cell bodies for the preganglionic parasympathetic vagal neurons that innervate the heart reside in the nucleus ambiguus.

Plan of the upper portions of the glossopharyngeal, vagus, and accessory nerves.

Glossopharyngeal nerve

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Cranial nerve that exits the brainstem from the sides of the upper medulla, just anterior to the vagus nerve.

Cranial nerve that exits the brainstem from the sides of the upper medulla, just anterior to the vagus nerve.

Plan of the upper portions of the glossopharyngeal, vagus, and accessory nerves.
Inferior view of the human brain, with the cranial nerves labelled.
Dura mater and its processes exposed by removing part of the right half of the skull, and the brain.
Hind- and mid-brains; postero-lateral view.(
Alveolar branches of superior maxillary nerve and sphenopalatine ganglion.
Upper part of medulla spinalis and hind- and mid-brains; posterior aspect, exposed in situ.
Hypoglossal nerve, cervical plexus, and their branches.

Fibers leaving the nucleus ambiguus travel anteriorly and laterally to exit the medulla, along with the other components of CN IX, between the olive and the inferior cerebellar peduncle.

The digestive tract, with the esophagus marked in red

Esophagus

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Organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the stomach.

Organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the stomach.

The digestive tract, with the esophagus marked in red
The esophagus is constricted in three places.
A mass seen during an endoscopy and an ultrasound of the mass conducted during the endoscopy session.

The upper striated muscle, and upper esophageal sphincter, are supplied by neurons with bodies in the nucleus ambiguus, whereas fibers that supply the smooth muscle and lower esophageal sphincter have bodies situated in the dorsal motor nucleus.