Perihypoglossal nuclei (also perihypoglossal complex, perihypoglossal nuclear complex, or satellite nuclei) are three prominent groups of neurons in the caudal

medulla oblongata The medulla oblongata or simply medulla is a long stem-like structure which makes up the lower part of the brainstem. It is anterior and partially inferior to the cerebellum. It is a cone-shaped neuronal mass responsible for autonomic (involun ...

near the

hypoglossal nucleus The hypoglossal nucleus is a cranial nerve nucleus, found within the medulla. Being a motor nucleus, it is close to the midline. In the open medulla, it is visible as what is known as the '' hypoglossal trigone'', a raised area (medial to the v ...

: the nucleus prepositus hypoglossi, intercalated nucleus, and

sublingual nucleus In the substance of the formatio reticularis are two small nuclei of gray matter. The one near the dorsal aspect of the hilus of the inferior olivary nucleus is called the Sublingual nucleus (inferior central nucleus, nucleus of Roller.) Referenc ...

. They are involved in controlling eye movements: they send their principal projections to the three

cranial nerve nuclei A cranial nerve nucleus is a collection of neuron cell bodies (gray matter) in the brain stem that is associated with one or more of the cranial nerves. Axons carrying information to and from the cranial nerves form a synapse first at these nucl ...

controlling extrinsic eye muscles via the

medial longitudinal fasciculus The medial longitudinal fasciculus (MLF) is a prominent bundle of nerve fibres which pass within the ventral/anterior portion of periaqueductal gray of the mesencephalon (midbrain). It contains the interstitial nucleus of Cajal, responsible ...

Anatomy

is a group of

neuron A neuron (American English), neurone (British English), or nerve cell, is an membrane potential#Cell excitability, excitable cell (biology), cell that fires electric signals called action potentials across a neural network (biology), neural net ...

s in the floor of the

fourth ventricle The fourth ventricle is one of the four connected fluid-filled cavities within the human brain. These cavities, known collectively as the ventricular system, consist of the left and right lateral ventricles, the third ventricle, and the fourth ...

, close to the nucleus of the hypoglossal nerve in the gray substance of the

, all of which contain cells with characteristics suggestive of reticular connections.

Afferents

Perihypoglossal nuclei receive afferents from the

cerebral cortex The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. It is the largest site of Neuron, neural integration in the central nervous system, and plays ...

vestibular nuclei The vestibular nuclei (VN) are the cranial nuclei for the vestibular nerve located in the brainstem. In Terminologia Anatomica, they are grouped in both the pons and the medulla in the brainstem The brainstem (or brain stem) is the poste ...

, accessory oculomotor nuclei, and

paramedian pontine reticular formation The paramedian pontine reticular formation (PPRF) is a subset of neurons of the oral and caudal pontine reticular nuclei. With the abducens nucleus it makes up the horizontal gaze centre. It is situated in the pons adjacent to the abducens nu ...

Efferents

The nuclei project principally to all three

controlling extrinsic eye muscles (the oculomotor (CN III), trochlear (CN IV), and abducens (CN VI) nuclei) via the MLF, with additional efferents to the

cerebellum The cerebellum (: cerebella or cerebellums; Latin for 'little brain') is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as it or eve ...

, and

thalamus The thalamus (: thalami; from Greek language, Greek Wikt:θάλαμος, θάλαμος, "chamber") is a large mass of gray matter on the lateral wall of the third ventricle forming the wikt:dorsal, dorsal part of the diencephalon (a division of ...

References

{{Reflist Neuroanatomy