The brain stem is located at the base of
the brain, in front of the cerebellum. Through it travel
all information signals from the remainder of the brain to
the body, and vice versa. In fact, the lowest
portion of the brainstem, known as the medulla, merges with
the top of the cervical spinal cord. In addition, the
brainstem contains many centers or nuclei, which supply the
cranial nerves (these nerves travel face and head), and the
brainstem is also responsible for such vital functions
as keeping us awake versus in a coma, breathing and other
basic "housekeeping" functions of the body.
From top to bottom, the brainstem may be
divided into several segments: the midbrain, the pons
and the medulla. Situated within the substance of the
brainstem are the cranial nerve nuclei.