脑干位于后颅窝中。由中脑、桥脑、延髓三部分组成。前上部为中脑,上与间脑相连。后下部为延髓,下与脊髓相接。中脑和延髓之间为桥脑。脑干与小脑联系有延髓的绳状体为小脑下脚,桥脑的桥脑臂为小脑中脚,中脑的结合臂为小脑上脚。脑干是连接脊髓、大脑、小脑的中间枢纽,由脊髓上行至丘脑而最后 Brainstem in the posterior fossa. By the brain, pons, medulla composed of three parts. The upper part of the upper brain, connected with the diencephalon. After the lower part of the medulla oblongata, next to the spinal cord phase. Between the brain and medulla oblongata pons. Brainstem and the cerebellum connected with the medulla oblongata of the cerebellar hypothalamus, pons the bridge of the cerebellum in the middle leg, the binding arm of the cerebellum for the cerebellum. The brainstem is an intermediate junction connecting the spinal cord, the brain, and the cerebellum, traveling up the thalamus from the spinal cord and finally