Page 1

1


2

3


THE AMAZING BRAIN THE BRAIN should need no introduction. You should know it intimately. After all, the brain is what makes you you. But it's a paradox that the organ that lets you know and connect with the world understands so little about itself. Now, thanks to stunning research building upon decades-no, centuriesof investigation, science is peeling away the layers of mystery to reveal how three pounds of flesh create an entire universe inside your head.

KNOWING ITSELF NERVE CELLS GLOSSARY ANATOMY LOOKING INSIDE

4

5


KNOWING ITSELF IT'S NOT MUCH to look at. Hippocrates, the Greek healer identified with the birth of medicine more than 2,000 years ago, thought it was made of moist phlegm. English philosopher Henry More, writing in the 1600s, compared it to bone marrow, a bowl of curds, or a cake of suet. Modernday neurologist Richard Restak says it resembles nothing so much as a large, wrinkly, squishy walnut. Looks can be deceiving. The brain, a three-pound chunk of organic matter, is not only the body’s most marvelous organ, it is the most complicated object known. It is “wider than the sky,” wrote poet Emily Dickinson. “For, put them side by side, / The one the other will contain / With ease, and you beside.” UNDERSTANDING THE BRAIN It is humbling to consider the brain and all that it does in every moment of our lives. In this corrugated mass of flesh, a staggeringly complex symphony of electrochemical reactions plays out every second of every day. Much of it does so without need of any conscious conductor to direct the ongoing melody. The brain makes the lungs The brain makes the lungs expand with the inrush of air, the heart pump blood, and the immune system fight off infection. It monitors pain and pleasure, signals when

6

to eat and when to sleep, houses memones and thoughts, and manufactures dreams and ideas. It processes sounds and sights, smells and tastes, and feelings ranging from the subtle to the sublime.

THE HUMAN ORGAN Beyond the work the brain does automatically comes something far different than mere mechanics. Out of the human brain arises consciousness-the unique ability

of Homo sapiens, "thinking man," to be aware of being aware. Consciousness, sometimes referred to as mind or possibly as soul, is difficult to define. A person in a deep sleep or a coma lacks an awareness, an alertness, that a waking person possesses. This heightened state of knowing about the world, and knowing about the knowing, is part of the definition. The conscious brain chooses and acts. It assembles words through language and communicates ideas. It commands muscles to move, directing the backhand volley of a tennis racket and the driving of a race car. It allows parents to recognize their children, and children to bond with their parents. It is responsible for Shakespeare's plays, Mozart's music, and Einstein's mathematical formulas. THE BRAIN AT WORK Truly, the thoughts, feelings, and memories that arise in the human brain are what define the species as well as being what make each person a ullique member of the human family. All of these marvels occur beyond the resolution of the human eye. As it labors, the brain does not expand like the lungs or contract like a muscle. It carries out its work electrochemically at the molecular level. Much of the process of observing the brain rests on the ability to scan its interior

with sophisticated computergenerated images requiring the use of x-rays, radioactive isotopes, and magnets. Small wonder, then, that only recently has science been External stimuli can physically alter the brain. For example, stress weakens the encoding of memories. able to examine the brain in detail and begin to explain its workings. Relying on macroscopic observation alone, research into the brain started extremely slowly. THE ANCIENT BRAIN More than 4,000 years ago, Egyptian priests considered the brain to be worthless. After a person's death, the most important organs were often removed and preserved. Prized above all was the human heart, which the priests believed contained the soul and the mind. In preparing a body for mummification, they slithered a hooked tool through the nose, removed the brain, discarded it, and packed the empty skull with cloth. The Greek philosopher Aristotle (384-322 B.C.) was of the same mind as the Egyptians, believing the brain to be merely an elaborate series of channels designed to cool the blood as it circulated throughout the body. Like the Egyptians, he considered the heart to be the paramount organ of the mind and of thought.

Although science has since discarded the idea of the heart as the home of humanity's essence, our language is replete with examples of the ancient idea clinging to the imagination. This is especially true in love and romance. We speak of losing a heart to a loved one, suffering a broken heart, and being heartsick. In reality, falling in and out of love is a matter of losing our brain-or perhaps, as anyone insane with romance could tell you, our mind. STAYING SHARP

YOUR BRAIN DOES not remain static, and there are ways to improve its performance. Like the muscles of your body, your brain gets stronger when it's given a workout. Creativity, imagination, and other methods of cognition improve when your brain reacts to new perceptions, particularly if you actively try to experience the world in fresh ways. Read and think. Soak up the art at a museum. Listen to complex music, and let your mind explore its patterns. Enjoying music stimulates many sections of the brain and presents the opportunity for creating new brain circuitry. Some scientific research, which was summarized in a book by physicist Gordon L. Shaw, suggests that listening to pleasurable music such as a Mozart sonata causes a short-term increase in the ability to solve spatial problems. Neurologist Richard Restak concurs with this finding. He believes that listening to Mozart for a few minutes each day may boost your cognition across many levels, from simple perceptions to deeper thoughts. Eine kfeine Nachtmusik, anyone?

7


8

9


Brain The Perfect Creation 10

Assignment 1  

To mdm Zuriani