People are living longer thanks to improvements in physical health. But to get the most from those additional years of life, cognitive health needs to keep pace.
Scientists at the University of Texas at Dallas tested a theory recently, and have concluded that just as physical strength is enhanced through vigorous exercise, it also takes challenging mental chores to keep the brain sharp.
While engaging in stimulating exercises like crossword puzzles may help, the researchers speculated that it was the active process of learning tasks that keeps an aging brain from losing ground.
To test the theory, the researchers set up three groups of older subjects.
Learning new tasks
One group was assigned to the high-challenge task of spending at least 15 hours per week for 14 weeks learning progressively more difficult skills in digital photography, quilting, or a combination of both.
Another group was assigned low-challenge tasks. Its members met for 15 hours per week to socialize and engage in activities related to subjects such as travel and cooking, with no active learning taking place.
The control group engaged in low-demand cognitive tasks such as listening to music, playing simple games, or watching classic movies.
All the participants were tested before and after the 14-week period and a subset was retested a year later.
Better memory performance
The researchers say their theory was validated. The high-challenge group demonstrated better memory performance after the experiment, and an increased ability to control brain activity more efficiently. They performed better at word recognition and this increase in efficiency was still present a year later.
Brain scans showed increased neural efficiency in judging words – displaying little activity when words were easy and increasing activity as words got harder. The researchers say that is a pattern of response that is typical of young adults.
Before the experiment, the older adults in the high-challenge group were processing every item, both easy and hard, with maximum brain activity. After going through the exercise, they were able to modulate their brain activity to the demands of the task, meaning they made a more efficient use of brain resources. This change in modulation was not observed in the low-challenge group.
What does it mean? It could mean that people need to keep learning things as they get older. Typically, however, many older adults tend to resist learning new things.
"The present findings provide some of the first experimental evidence that mentally-challenging leisure activities can actually change brain function and that it is possible that such interventions can restore levels of brain activity to a more youth-like state,” senior author Denise C. Park said in a release, explaining the results.
Park said further research is needed to determine if this effect is universal and to understand who would benefit most from challenging learning exercises.