Pons

NervousOrgansHead

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What it is
The bulging middle part of the brainstem, lying on the clivus in front of the cerebellum. Transverse fibres wrap its front and sweep back on each side as the thick middle cerebellar peduncles; the basilar artery runs in the groove down its midline.
Function
Relays signals from the cerebral cortex to the cerebellum, houses the nuclei of cranial nerves V-VIII and helps control breathing rhythm and sleep (REM).
Size
About 2.5 cm long, 3-3.5 cm wide
Clinical note
A stroke in the ventral pons can cause locked-in syndrome: complete paralysis with consciousness and vertical eye movements preserved.

Nearby nervous structures Abducens nerve root (CN VI), Cerebral aqueduct, Facial nerve root (CN VII), Fourth ventricle, Glossopharyngeal nerve root (CN IX), Oculomotor nerve root (CN III), Trigeminal nerve root (CN V), Trochlear nerve root (CN IV), Vestibulocochlear nerve (CN VIII), Vestibulocochlear nerve root (CN VIII)