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The structures of the tegmentum reflect the functions of the pons and its cranial nerves. Sensation from the face arrives in the trigeminal nerve and distributes to the chief sensory nucleus, the mesencephalic tract and nucleus and the tract and nucleus of spinal V; muscles of mastication are served by the motor nucleus of V. The lateral rectus muscle of the eye is served by the abducens nucleus near which lies the center for the control of horizontal lateral gaze (PPRF). The MLF connects to the oculomotor nucleus of the midbrain to integrate with the medial rectus muscle and incorporates vestibular information. The auditory division of the CN 8 enters at the pons-medulla junction. Its fibers synapse in the cochlear nuclei and the central auditory pathway continues via the lateral lemnisci (with some synapses in the superior olives) to the inferior colliculus. The vestibular division of CN 8 also enters at the pons medulla junction and terminates in the vestibular nuclei which is an extensive area from high pons through the open medulla. Its connections are to the cerebellum, CN 3,4 and 6, and forms the vestibulospinal tracts. The 7th cranial nerve has motor and sensory components. The motor components serve the muscles of facial expression and secretomotor functions of the lacrimal and salivary glands; general and special sensory (taste) functions are represented in the nucleus solitarius.