Page 46 - The Memory Program How to Prevent Memory Loss and Enhance Memory Power

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make up for this loss. But in cells that do not reproduce and are meant to last a lifetime, especially
those in the brain, programmed cell death may play a major role. Just as there are genes that tell each
cell to synthesize the right kinds of proteins to maintain life, other genes are programmed to turn off
protein synthesis and destroy the cell. Currently, we do not know what triggers these “suicide ’’
genes to come alive as we grow older. If the genes that trigger programmed cell death are
successfully blocked, the human life span can be greatly prolonged. But what will society be like if
new genetic therapies make people live to the age of 150 or 200 years? If in addition to increased
longevity there is a corresponding improvement in quality of life, then the ensuing problems won't be
as overwhelming as we now imagine.

Biological Clocks

Programmed cell death is like the entire assembly line going on permanent strike, leading to factory
closure. Disruption of biological clocks is the entire managerial staff, including the chairman and
board of directors, calling it quits. Many of the natural ebbs and flows in the body— including sleep,
body temperature, and hormone secretion— are under the control of biological clocks that are
genetically programmed to react according to set time sequences, such as the twenty-four-hour day,
based on environmental inputs. As our DNA decays with aging, these natural rhythms become erratic
and begin to desynchronize, weakening our natural defenses against disease. Gradually, over time,
the disruption of biological clocks becomes a central feature of the aging process.

By itself, this theory does not explain why we age the way we do. Many bodily functions do not
have natural biological clocks, and only a few of the brain's functions, particularly sleep, are under
this type of rhythmic control. Even the heart, a structure that requires near-perfect rhythmic
performance to ensure survival, is not affected very much by circadian (twenty-four-hour) rhythms.

Free Radicals Are Toxic

That's what some people said in the 1960s and 1970s. But jokes aside, what exactly are free radicals?
Free radicals are formed when an atom or molecule carries an unpaired electron. This extra negative