Why Head Injuries Are So Dangerous
There's no disputing the fact that a bump on the head is much different than a bump on the knee, and that the bump on the head produces broader implications for long-term health. Depending on what part of the head is injured (and, therefore, the passageways in the brain that are damaged), the injured person can lose the ability to speak or walk or even remember his name. The brain, after all, regulates all body functions. It tells us what to think and what to feel, and it is what makes us human—and unique.
There are six distinct areas of the brain. Each of those areas controls different body functions that can be affected or disabled as the result of a head injury.
This list looks at each of the different parts of the brain in detail and outlines the function of each—which can be affected if that part is accidentally damaged. It will help you understand what's going on if a head injury occurs.
- CNS No, it's not a new bank. The CNS is the central nervous system, and it functions as the go-between that sends messages back and forth from the masses of peripheral nerves in the body to the spinal cord that leads to the brain. Damage here can affect a person's ability to move.
- Brainstem You'll find the brainstem at the uppermost tip of the spinal cord. Connected to the spinal cord by thick nerve fibers, it's the invisible underbelly of the “corporation.” It is divided into three areas: the Medulla is the place where basic life functions such as heartbeat, temperature, and breathing are regulated. Moving up the brainstem, we next come to the Pons: the bridge between the medulla and the “upper echelons” of the brain. It is also the area where reflexes are controlled and instinctively used, and it houses the brain's alarm nerve cells that keep you alert. The third area of the brainstem is the Midbrain, which provides eye muscle control, as well as helping the Pons with its basic job.
- Cerebellum Located behind the brainstem, the cerebellum is the body's center for balance and coordination: every step and every movement is regulated from here. The cerebellum acts as a traffic coordinator of your body's corporation, too. It coordinates your movement and your speech muscles.
- Diencephalon Considered the “outer corridor” of mind power, the diencephalon sits above the brainstem, as a proud, majestic gateway to the emotional and mental depth above. Here, the hypothalamus and the thalamus—the partners in crime— decipher every sensation. These two partners also delegate where memory will be stored.
The thalamus is a beehive of activity through which messages are transported to the place that determines who gets what in the “upper echelons” of power. To illustrate its function, think of this. The words of the poem you're reading sit next to your recipe for veggie burgers in your memory storage tank. The words of the poem are sent to both the emotional core of the brain (where they affect your feelings) and the intellectual center of the brain (where they are deciphered and analyzed). They bounce from emotion to intellect and evoke the deep sigh you produce. In the meantime, the smell of those cooking veggie burgers is sent to the brainstem, which activates your salivary glands in anticipation of lunch. All this and more. The thalamus never stops!
Short-term memory enables you to remember things about this morning or the movie you saw at the mall last week. Long-term memory accounts for those deep-seated remembrances of long-ago birthday parties, old friends, and music to which you once danced the night away. It also “locks in” repetitious, rote-learned motor skills, such as how to tie your shoe. The two types of memories are kept in “chemical loops” in different parts of the brain. Because short-term memory is stored in an area that's vulnerable to head injury and it has not yet become ingrained in the brain by repetition, it is usually more affected from an accident.
More on: First Aid
Excerpted from The Complete Idiot's Guide to First Aid Basics © 1996 by Stephen J. Rosenberg, M.D. and Karla Dougherty. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.
To order this book visit Amazon's web site or call 1-800-253-6476.