Tegmental pontine reticular nucleus

Brain: Tegmental pontine reticular nucleus
Latin	nucleus reticularis tegmenti pontis
NeuroNames	hier-563

The tegmental pontine reticular nucleus (or pontine reticular nucleus of the tegmentum) is an area within the floor of the midbrain. This area is 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 pontine nuclei 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.

See also

• Pontine tegmentum

References