Forgetting why you walked into a room, put your car keys or blanking on someone's name may sound like a list of the early signs of Alzheimer's disease.
But the common lapses in memory are what many twentysomethings experience and blow off.
Research tracing the gradual decline of memory says that the process begins at the ripe age of 20 and as brain cells slip away, gone forever, the chemicals that help the brain work efficiently are also not being produced in the same quantities as when you were a fast-thinking teen.
In studies of more than 350 men and women between the ages of 20 and 90, psychologist Denise Park found that normal memory loss in adults in their 20s and 30s affects their everyday lives in minor ways, such as forgetting a commonly used phone number or a person's name.
"Younger adults in their 20s and 30s notice no losses at all, even though they are declining at the same rate as people in their 60s and 70s, because they have more capital than they need," says Park, who directs the Center for Aging and Cognition at the University of Michigan Institute for Social Research (ISR) and who appears in The Secret Life of the Brain, a new PBS series funded by the National Science Foundation.
Using Computer Memory and Not Your Own?
But other recent research suggest that sections of the brain that strengthen memory are becoming flimsy and weak in a generation reliant on computers. With an increasing reliance on computers for research and guidance, as well as Palm pilots and navigation devices, instead of exercising these parts of the brain, young adults just search the Web or punch some words into a gadget, say researchers.
A preliminary study released earlier in the year looked at 150 20- to 35-year-olds in Japan and found that more than one in 10 were suffering from severe memory problems. Researchers from Hokkaido University's in Japan said the memory dysfunction was enough to further study the possible connection between reliance on computer gadgets, organizers and automatic car navigation systems.
"They're losing the ability to remember new things, to pull out old data or to distinguish between important and unimportant information. It's a type of brain dysfunction," said Toshiyuki Sawaguchi, the university's professor of neurobiology. "Young people today are becoming stupid."
Park agrees that an increase in experience and general knowledge, as measured by vocabulary, compensate for memory loss.
But when people use the computer as a kind of external memory device, vocabulary, general knowledge and experience are not stored in the body's own "hard drive," instead they reside on the World Wide Web.
"Cognitive performance is a direct result of brain activity and brain structure much like cardiovascular fitness relates to our ability to exercise and perform physical tasks," Park said
Exercising the Brain Like a Bicep
By the time people are in their mid-60s, according to Park, the continuous decreases in cognitive abilities may become noticeable.
Park is now embarking on a grand study of the brains of younger and older minds at work. By linking behavioral testing and neuroscience, she is studying what parts of the brain older adults use for different types of mental tasks compared to younger adults, and what patterns of brain activation high-performing older adults show compared to their lower-performing peers.
"Only 40 years ago, we had little understanding of how smoking and cholesterol levels were related to cardiovascular health," Park said. "It's likely that just as diet and exercise help to keep our bodies fit and healthy, we'll find ways to improve the functioning of our aging minds."