By Laura Helmuth, Scientific American
Studies suggest cognition and brain structure and function improve in response to improvement in fitness. Why does physical activity have such an effect on mental abilities? It may have to do with the link between physical activity and disease. Physical activity reduces the risk of cardiovascular-related death, type 2 diabetes, colon and breast cancer, and osteoporosis.
Fitness Training and Changes in Brain Structure
Psychologist Stanley J. Colcombe, then at the University of Illinois, and his colleagues examined the influence of fitness training on potential changes in brain structure. The six-month trial included 59 healthy but sedentary volunteers, age 60 to 79.
Brain scans after fitness training showed that even relatively short exercise interventions can begin to restore some of the losses in brain volume associated with normal aging. Kirk Erickson and his colleagues found that an hour a day for three days a week over the course of a year increased the volume of the hippocampus in older adults, a part of the brain that is crucial for memory.
Researchers have found that brain regions that need to communicate with one another to support memory, reasoning, and problem-solving become more poorly connected as we age.
A study by Michelle Voss of the University of Illinois and her colleagues found that when older adults participated in a six-month walking program, connections increased in a number of brain networks, and this increased connectivity was associated with improvements in executive-control processes such as scheduling, planning, dealing with ambiguity, and working memory.
Factors that Boost Mental Fitness
Doing puzzles and push-ups are helpful for some—but other factors also boost mental fitness. Getting involved in social groups both improves cognition in general and seems to delay the onset of dementia.
The traditional focus of this research has been on relatively objective measures of social isolation versus connectedness, including the extent to which a person participates in activities that prominently involve social interaction, such as doing volunteer work, the number of friends and relatives an individual communicates with regularly (in other words, the size of a person’s social network), and marital status.
Some findings suggest positive attitudes and beliefs improve adult cognition, but those results are spottier. Positive beliefs and attitudes may have indirect effects by influencing behaviors such as exercise and mentally stimulating activities that are associated with cognitive enrichment.
More generally, individuals who are optimistic, agreeable, open to new experiences, conscientious, positively motivated, and goal-directed are more likely to age successfully, to take advantage of opportunities, to cope effectively with life circumstances, to effectively regulate emotional reactions to events, and to maintain a sense of well-being and life satisfaction in the face of challenge.
This is a transcript from the video series Understanding Your Inner Genius. Watch it now, on Wondrium.
Factors leading to Cognitive Decline
Just as some activities may reduce risk of cognitive decline, other patterns of behavior may increase the risk.
Chronic psychological distress—resulting from depression, anxiety, and negative emotions such as anger and shame—is associated with a variety of negative outcomes in adulthood, including cognitive decline.
The tendency to disproportionately experience psychological distress is called neuroticism. Studies have found a higher level of neuroticism to be linked to an increased risk of Alzheimer’s disease and mild cognitive impairment in old age.
Health Prevention Model
Public policy should follow a health prevention model that takes this research into account. Supporting the Elderhostel movement or adult continuing education could help older adults engage in intellectual activities.
A critical issue is how to promote physical exercise and social interactions in midlife during the working years. Future research should address whether work-related activity programs, such as availability of exercise facilities at or near the workplace, foster an enriching lifestyle.
Potential for Maximizing Human Performance
It is important to know that there is some controversy about the magnitude and durability of mental exercise outcomes. Companies are marketing computer games and other means of exercising the mind, often making strong claims about the effectiveness of expensive products—claims that have not been backed by actual scientific studies.
Consumers should look for evidence demonstrating the benefits of such products—particularly with regard to everyday activities, such as driving, memory, and decision-making—and be especially wary of bold or miraculous claims.
We may soon discover the potential for maximizing human performance through cognitive enrichment. Advances in medical science have led to increased longevity through effective treatments for many illnesses that increase the risk of dementia. Similarly, we hope, advances in psychological science can improve the quality of life and show how behavioral interventions can help us all age successfully.
Common Questions about the Relationship between Physical and Mental Fitness
Brain scans after fitness training have shown that even relatively short exercise interventions can begin to restore some of the losses in brain volume associated with normal aging. A study found that an hour a day for three days a week over the course of a year increased the volume of the hippocampus in older adults, a part of the brain that is crucial for memory.
A study by Michelle Voss of the University of Illinois and her colleagues found that when older adults participated in a six-month walking program, connections increased in a number of brain networks, and this increased connectivity was associated with improvements in executive-control processes such as scheduling, planning, dealing with ambiguity, and working memory.
Chronic psychological distress—resulting from depression, anxiety, and negative emotions such as anger and shame—is associated with a variety of negative outcomes in adulthood, including cognitive decline.
