The oral pontine reticular nucleus, or rostral pontine reticular nucleus is one of the two components of the medial (efferent/motor) zone of the pontine reticular formation - the other being the

caudal pontine reticular nucleus The caudal pontine reticular nucleus or nucleus reticularis pontis caudalis is a portion of the reticular formation, composed of gigantocellular neurons. In rabbits and cats it is exclusively giant cells, however in humans there are normally size ...

. The efferents of these two structures together give rise to the medial (pontine)

reticulospinal tract The reticular formation is a set of interconnected nuclei in the brainstem that spans from the lower end of the medulla oblongata to the upper end of the midbrain. The neurons of the reticular formation make up a complex set of neural networks i ...

(which modulates the muscle tone of the trunk and limb musculature). A population of their neurons together also form the

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 ...

which is involved in the coordination of horizontal conjugate eye movements in response to head movements.

Anatomy

This nucleus tapers rostrally to transition into the caudal mesencephalic reticular formation. It contains sporadic giant neurons.

Afferents

It receives sensory and motor cortical afferents via corticoreticular fibers.

Research

Different populations of the pontis oralis have displayed discharge patterns which coordinate with phasic movements to and from paradoxical sleep. It is thus apparently involved in the mediation of changing to and from

REM sleep Rapid eye movement sleep (REM sleep or REMS) is a unique phase of sleep in mammals (including humans) and birds, characterized by random rapid movement of the eyes, accompanied by low muscle tone throughout the body, and the propensity of the s ...

.Dergacheva OIu et al. Impulse activity of neurons in the nucleus pontis oralis in cats during sleep--wakefulness cycle. Ross Fiziol Zh Im I M Sechenova. 2002 Dec;88(12):1530-7.

References

Pons Neuroscience of sleep {{Neuroanatomy-stub