 Before turning to arguments for and against the whole-brain standard, it may be helpful to review some basic facts about the human brain, “whole-brain death” (total brain failure), and other states of permanent (irreversible) unconsciousness. (The most important terms for our purposes appear in italics.) We may think of the brain as comprising two major portions: (1) the “higher brain,” consisting of both the cerebrum, the primary vehicle of conscious awareness, and the cerebellum, which is involved in the coordination and control of voluntary muscle movements; and (2) the “lower brain” or brainstem. The brainstem includes the medulla, which controls spontaneous respiration, the reticular activating system, a sort of on/off switch that enables consciousness without affecting its contents (the latter job belonging to the cerebrum), as well as the midbrain and pons.