Zombie CSU (22 page)
PMI: Calculating the Postmortem Interval
The timetable for the process of death and decay is important to all aspects of murder investigation. It unfolds like this:
Algor mortis
: (Latin:
algor
—coolness;
mortis
—of death) The process a body goes through after death during which the body cools to ambient temperature. Temperature drops at approximately 1 to 1.5 degrees Fahrenheit per hour.- Rigor mortis
: (literally “death stiffness”) The stiffening of the limbs following death as muscle cells decay. - Vitreous humor changes
: There is a clear gel that fills the gap between the retina and the lens of the eye. Following death the potassium levels in this gel increases at a measurable and predictable rate, which allows forensics experts to use it to measure time elapsed since death. - Entomology
: Insects always appear on a corpse and are crucial to its decomposition. - Autolysis
: (literally “self-splitting”) This is the process of postmortem cell disintegration. - Putrefaction
: The decomposition of proteins by anaerobic microorganisms called putrefying bacteria.
Most of the cranial cavity is filled by the cerebrum, a large rounded structure divided into two hemispheres, and each hemisphere is further divided into four sections, the frontal, parietal, temporal, and occipital lobes. The two hemispheres are primarily linked to the corpus callosum (a very large bundle of nerve fibers) through which the two “half brains” communicate with each other. This commissure transfers information between the two hemispheres to coordinate localized functions. The cerebrum controls a variety of functions (motor, sensory, and higher mental functions, such as thought, reason, emotion, and memory) and integrates their actions. It consists of both gray and white matter. The gray matter is mostly composed of neurons (cell bodies) while the white matter primarily contains axons (nerve fibers). The majority of the cerebrum consists of white matter.
Zombie Oops!
“Using the mythology Romero put forth I realized there is a small problem. In both versions of
Night of the Living Dead
Johnny (brother of the female lead, Barbara) dies by his head being crushed. This would have damaged the brain, and since that is how to stop a zombie in the first place it makes you wonder how he came back in the first place.”—Damien Rogers, zombie movie fan
Each hemisphere has an outer layer of gray matter called the cerebral cortex. The motor cortex is the part of the cerebral cortex in the brain that controls the actions of voluntary muscles; different parts of the motor cortex control different specific muscle functions. It can be presumed that in zombies there is some function of the motor cortex. The jerky movements and (in some cases) apparently dead limbs are indications of damage to this center of the brain or perhaps the cerebellum.
In the cerebrum, there are fifty to one hundred thousand neurons; information is sent from place to place like a telegram. The neuron cell bodies would be the telegraph machine itself while the axons would be the wires connecting it to other machines.
The right hemisphere organizes or sorts information; the left hemisphere analyzes the information collected by the right.
Certain mental functions (e.g., mathematics, logic, language) are lateralized in the brain, meaning they are located in either the right or left side of the brain. Generalizations are made about these functions (e.g., logic, creativity), but they need to be treated carefully because popular lateralizations are often distributed across both sides. Lateralization of these functions also depend on whether or not the person is right-handed versus left-handed. Since the majority of people are right-handed, the distribution of mental functions (see the sidebar, “Brain Function”) is done with that in mind (in a left-handed individual, the lateralization is usually located in the opposite hemisphere from that of someone who is right-handed).
Art of the Dead—Kelly Everaert
Zombie Biohazard
“
Night of the Living Dead
scared the crap out of me. I was probably ten or eleven watching the late night movie on Halloween after a night of trick or treating. At least one channel played this classic movie every Halloween and I’ve watched it every year since.”
Brain Function
Left Hemisphere Functions | Right Hemisphere Functions |
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The best example of lateralization for one specific ability is language. Both sides contain major areas in language skills, but each have separate properties. Linear reasoning functions of language (e.g., grammar, word production) is lateralized to the left hemisphere while holistic reasoning (e.g., emphasis, prosody) are lateralized to the right hemisphere.