The ups and downs of life may seem to have no predictable plan. But scientists now know there are very definite life patterns that almost all people share. Today, when we live 20 years longer than our great-grandparents, and when women mysteriously outlive men by seven years, it is clearer than ever that the “game of life” is really a game of trade-offs. As we age, we trade strength for ingenuity, speed for thoroughness, and passion for reason. These exchanges may not always seem fair, but at every age, there are some advantages. So it is reassuring to note that even if you've passed some of your “prime”, you still have other prime years to experience in the future. Certain important primes seem to peak later in time.
WHEN ARE YOU SMARTEST? From 18 to 25, according to IQ scores; but you are more experienced with increasing age. You're sharpest in your 20's; around 30，memory begins to decline, particularly your ability to perform mathematical computations. “But your IQ for other tasks climbs,” says Berkeley psychologist Arthur Jensen. Your vocabulary at age 45, for example, is three times as great as when you graduated from college. At 60, your brain possesses almost four times as much information as it did at age 21. This trade-off between sharpness and wisdom has led psychologist Dr.Leopold Bellak to suggest that “maturity quotients" (MQs instead of IQs) be adopted for adults.
WHEN ARE YOU HEALTHIEST? For men, from 15 to 25; for women 15 to30.
“A man is in his best shape in the decade before age 25,”says New York internist Dr.Donald Tomkins.“His muscles are firmest, his resistance to colds and infection is highest, and his body is most efficient in utilizing nutrients.” Women, for reasons scientists do not understand, get a five-year bonus. Peak health begins to decline when the body process called anabolism (cell growth) is overtaken by the opposite process, catabolism (cell death).“Cells have been dying since bith,” says Tomkins,“but in our late 20's, they start dying faster than they are replaced.”Also, muscle is replaced with fat.
Women also get an additional bonus of good health later in life. The figures of National Institute of Health show that the onset of such “old age” diseases as arthritis, 0.rheumatism and heart ailments denies the generally greater fitness of women: Life expectancy for men is now 68.3; for women 75.9. U.S. aging authority William Kannel says, “Older women with low blood pressure are practically important." However, psychologists believe that by entering the competitive job market in increasing numbers, women may eventually give up their statistical advantage.
the quality of behaving in a sensible way like an adult (Para. 2)
【正确答案】：maturity
