Figure 2-1. The brainstem.
Cerebral peduncles--connecting the brainstem to the cerebrum.
Hindbrainstem, consisting of:
(a) Pons--concerned with transmission of impulses between the left
and right hemispheres of the cerebellum.
(b) Medulla--contains nerve centers for cardiac, vasomotor, and
respiratory functions. Also influences sneezing, coughing, hiccoughing, and vomiting.
b. The Cerebellum. The cerebellum (figure 2-2) is a spherical mass of nervous
tissue attached to and covering the hindbrainstem. It is attached to the brainstem by
three pairs of cerebellar peduncles. The cerebellum consists of three lobes; the right
hemisphere, left hemisphere, and a central portion called the vermis.
(1) The outer layer, or cortex, of the cerebellum is composed of "gray
matter." Gray matter is actually the cell bodies of neurons. Many folds (gyri) and
grooves (sulci) in the surface of the cortex give it a wrinkled appearance.