The pons is a structure which makes up the upper segment of the brain stem. Caudal to the midbrain and cranial to the medulla oblongata, the pons contains nerve fibers that connect the two halves of the cerebellum. The pons plays an important role in coordinating movements involving right and left sides of the body as it relays sensory information between the cerebellum and the cerebral cortex, controling arousal, and regulating respiration. Below the pons is the medulla, which is continuous with the spinal cord and transmits ascending and descending nerve fibers between the spinal cord and the brain. The pons is irrigated by pontine arteries.