of Life and Death
the Determination of Death
Apnea - lack
of spontaneous respiration
- procedure for determining the circulation of blood to an organ or region
of the body (e.g. the brain). Involves injecting a potentially harmful
(usually radioactive) dye.
Brain stem -
the stemlike portion of the brain that connects the cerebral hemispheres
to the spinal cord. It includes the pons, medulla oblongata, mesencephalon,
and (debatably) the diencephalon.
system depressants (CSN depressants) - "downers", e.g. barbiturates.
Cephalic - of
or relating to the head.
(brain stem reflexes) - reflexes controlled by the brain stem (e.g. pupil
response to light, "eye rolling", gag and cough).
Cerebral - of
or relating to the cerebrum (in general, the brain).
- absence of oxygen to the brain.
- the intricately folded outer layer of the cerebrum. About 40% of the
brain by weight.
brain) - the large rounded portion of the brain occupying most of the cranial
cavity, divided into two hemispheres.
- "a state during which all external signs of life (consciousness, reflexes,
respiration and cardiac activity) are absent, but the organism as a whole
is not yet dead; the metabolic processes of its tissues still proceed and
under definite conditions it is possible to restore all its functions;
i.e. this state is reversible under appropriate therapeutic intervention.
...[Excluding hypothermia and CSN depressants,] 5-6 minutes in the maximum
duration of the state of clinical death which the brain cortex of an adult
organism can survive with subsequent recovery of all its functions." (Negovskii,
quoted in M. Sabom, Recollections of Death)
deep sleep) - a trancelike state from which a person cannot be aroused
by external stimuli, is unresponsive to a wide range of stimuli, and is
usually considered to be unconsciousness. There are varying levels of coma,
depending on the range of nonresponsiveness.
Deep coma (coma
depasse) - complete or nearly complete unresponsiveness. Some spinal reflexes
(e.g. tendon reflexes) may remain. Although heartbeat and respiration may
be artificially sustained, no spontaneous heartbeat or respiration is attempted
by those in a deep coma. Flat EEG. Usually thought to be irreversible.
- those in whom the capacity for cerebral activity has been destroyed.
Roughly synonymous with being in a deep coma or being "brain dead."
- measurement of the electrical activity of the brain. Thought to correlate
with cognitive activity.
EKG (ECG: electrocardiogram)
- measurement of the electrical activity of the heart.
silence (flat EEG, isoelectric EEG) - no significant electrical activity
in the brain.
- body temperature below 90 degrees F (for a human).
simpliciter (ICS) - those who are irreversibly comatose without being
the outer layer of the brain. Believed to be the most recently evolved
part of the cerebral cortex. Includes all the cerebral cortex in a human,
except the hippocampal formation and piriform areas. Believed to be the
part of the brain that controls consciousness and the capacity for social
- state in which the neocortex has irreversibly ceased to function, but
brain stem activity remains. Subclass of ICS.
Website constructed and maintained
Douglas Shrader / Shradedw@Oneonta.edu
Updated February 4, 2002