APA Dictionary of Psychology

n. a part of the brainstem lying between the midbrain and the medulla oblongata, appearing as a swelling on the ventral surface of the brainstem. It consists of bundles of transverse, ascending, and descending nerve fibers and nuclei, including facial nerve nuclei. It serves primarily as a bridge, or transmission structure, between different areas of the nervous system. It also works with the cerebellum in controlling equilibrium and with the cerebral cortex in smoothing and coordinating voluntary movements. With the cerebellum, it forms the region called the metencephalon. —pontine adj.