The mind is not as agile as it once was, even at the ripe old age of 34. Names elude me, statistics slip away, memory fades. This is just the first step on a long journey into senescence; and by 74, if I make it that far, I might remember practically nothing. That age is the average of a cohort of 2,802 seniors who recently participated in a long-term study to see if anything can be done to reverse this age-related mind decline. The good news: there is.

Sherry Willis of Pennsylvania State University led a team of scientists that followed this group of adults, aged 65 and older, still living independently between 1998 and 2004. The seniors came from all walks of life, races, and parts of the country, including Birmingham, Ala., Detroit, Boston and other major cities. They all had one thing in common when the study commenced: no signs of cognitive impairment.

The researchers divided them into four groups of roughly 700 each: three groups that would receive training in either memory, reasoning or speed of processing and one that would serve as a control (with no particular instruction). "We wanted to assess the impact of training not only on mental functions but also on peoples' ability to perform certain everyday activities," says University of Florida psychologist Michael Marsiske, a co-author of the study.

Toward that end, the seniors in the training groups were broken down into small classes of four or so to receive 10 one-hour training sessions over the course of five weeks. Memory training consisted of mnemonic strategies for remembering word lists or texts, such as associating various words, visualizing them or organizing them in specific ways. Reasoning training taught them how to spot the pattern in a series, such as "a c e g i... ." The researchers boosted the subjects' processing speed via practice, practice, practice in identifying an object on a screen after increasingly short exposures.

Over the course of the next five years the researchers asked participants to appraise their skills and to report whether the training had helped with everyday tasks. They also independently evaluated the subjects' skills in things like finding items in a medicine cabinet. After training, 87 percent of the speed trainees, 74 percent of the reason trainees and 26 percent of memory trainees showed immediate improvement. That advantage over their untrained peers persisted over the next five years. "We were able to move them from needing almost one second to perceive [objects flashing on a screen] to needing less than three quarters of a second," Marsiske says. "The memory-trained group was able to remember, in a list of 12 to 15 words, about three to four more words than people who did not receive training."

Further, subgroups of the trainees received additional, "booster" training one year and three years after the initial effort. These folks performed best of all, especially those in the processing-speed group. "They were performing significantly more quickly and more efficiently on tasks like finding items in a pantry, making change [for purchases], looking up a number or reading medications," Marsiske notes.

Such training seemed to largely offset the cognitive decline suffered by nearly all of the controls as the years wore on; by the fifth year, significant skill gaps had opened between trainees and their untrained peers. The research holds out hope that simple mental exercise may play a key role in staving off dementia and other cognitive declines that currently afflict at least 24 million people worldwide.

But it is not as simple as continuing to do the crossword or sudoku puzzles that you love, the brain must be continually stretched and challenged. "To drive this effect, you have to practice things that you don't like or things you don't regularly practice," Marsiske says. "We hope to find ways of making these training programs more widely available to people and begin to encourage something more like mental exercise." There may be hope for me--for all of us--yet.