Growing Older

Tests do show that 70-year olds often take longer and make more mistakes than 20-year-olds on mental challenges such as memorizing lists or matching photos in a pile. But hidden within those results is the countervailing fact that, as people grow older, mental performance begins to differ markedly among individuals of similar ages, making it impossible to draw conclusions about an older person's abilities based on averages for his or her age. "The only thing you can assume about a 65 or 75-year-old is how many candles will be on the birthday cake," says Harvard University psychologist Douglas Powell. He tested 1 583 people from 25 to 92 years of age in reasoning, memory, and visual and spatial abilities. On various tests, he found that a quarter to a third of octogenarians performed as well as their younger counterparts. A fraction of people in their 80's and 90's ranked near the top of mental abilities for all ages. And even the lowest scorers suffered only modest declines that didn't interfere with daily living.

Powell's findings mirror other studies concluding not only that most people retain strong mental skills until at least age 70, but over a fourth go on well past that age without significant drops in brainpower. Scientists suspect that genetic and environmental factors play a part.

K. Warner Schaie, director of the Gerontology Center at Pennsylvania State University, finds that the factors most associated with strong mental function in older age groups include an above-average level of education, a complex and stimulating life-style and being married to a smart person.

Rigid adherence to routine and low satisfaction with life are associated with earlier deterioration of the intellect.

Short Answer Questions

1. What is the main idea of the first paragraph?
2. What is implied in the test of Douglas Powell?
3. At what age do most people have their strong mental abilities?
4. What kind of people are likely to have mental declines in old ages?
5. What is the passage mainly about?

(Keys.)