Tegmental pontine reticular nucleus

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Brain: Tegmental pontine reticular nucleus
Latin	nucleus reticularis tegmenti pontis
NeuroNames	hier-563
Dorlands/Elsevier	n_11/12583133

The tegmental pontine reticular nucleus (or pontine reticular nucleus of the tegmentum) is also known to affect the cerebellum with its axonal projections.

These efferent connections have been proven to project not only ipsilaterally, but also to decussate and project to the contralateral side of the vermis.

It has also been shown that the projections from the tegmenti pontis to the cerebellar lobes are only crossed fibers.

The n.r. tegmenti pontis also receives afferent axons from the cerebellum.

This nucleus is known for its large amount of multipolar cells and its particularly reticular structure.

The n.r. tegmenti pontis is topographically related to pontine nuclei (non-reticular), being just dorsal to them.

The nucleus reticularis has been known to mediate eye movements, otherwise known as so-called saccadic movement. This makes sense concerning their connections as it would require a nucleus which receives and projects to the cerebellum to mediate that kind of complex circuitry. Also, behaviorally this makes sense as no one thinks about saccadic movements when scanning a room and the saccadic movements are not directly controlled by the cortex.

The nuclei of the cerebellum are the most traditionally studied mostly because it is easy to see which nuclei degrade when the cerebellum is amputated.

The neurons of the lateral reticular formation are very important for reflexes and the mediation of posture. It has been shown in cats that electrical stimulation of the reticular formation can make a standing cat lie down. Conversely if the cat is stimulated in an alternate spot it can make a lying cat stand.

[edit] References

v • d • e Brain: reticular formation
Medial reticular formation: Gigantocellular - Caudal pontine - Oral pontine - Parvocellular - Ventral Lateral reticular formation: Lateral - Paramedian - Tegmental pontine

v • d • e Brain: rhombencephalon (hindbrain)
Myelencephalon/medulla	Arcuate nucleus of medulla, Solitary nucleus, Hypoglossal nucleus, Nucleus ambiguus, Olivary body, Inferior olivary nucleus, Cuneate nucleus, Accessory cuneate nucleus, Gracile nucleus, Inferior salivatory nucleus, Raphe nuclei (Obscurus, Magnus, Pallidus), Area postrema, Posterior nucleus of vagus nerve, Reticular formation (Gigantocellular nucleus, Parvocellular reticular nucleus, Ventral reticular nucleus, Lateral reticular nucleus, Paramedian reticular nucleus), Pyramid (Decussation)
Metencephalon/cerebellum	Vermis, Flocculus, Arbor vitae
Metencephalon/pons	Pontine tegmentum, Superior salivary nucleus, Trapezoid body, Pontine nuclei (Superior olivary nucleus, Trigeminal nerve nuclei, Abducens nucleus, Facial motor nucleus, Cochlear nuclei, Vestibular nuclei), Locus ceruleus, Paramedian pontine reticular formation, Median raphe nucleus - Reticular formation (Caudal pontine reticular nucleus, Oral pontine reticular nucleus, Tegmental pontine reticular nucleus)
Fourth ventricle	Obex, Median aperture