We all know that exercise is good for us, and a growing body of research shows that it helps our brains age well too. Scientists are now finding that physical activity is effective both at preventing and treating cognitive dysfunction over the course of a person’s life.
Researchers are still working to understand how the effects of exercise vary across ages and individuals and exactly how we all can make the most of exercise. In a recent study published in Psychological Science that looked at more than 1,000 people, Kirk Erickson of the University of Pittsburgh and colleagues suggested that a particular gene may influence the effects of exercise on working memory – helping to explain individual differences in the effects of exercise on cognitive performance.
Erickson, who will be presenting at the American Association for the Advancement of Science (AAAS) meeting in Chicago this weekend, spoke with CNS about the larger body of work, including common misperceptions about the link between exercise and cognition.
CNS: Your 2012 review paper in the Archives of Medical Research says that there is robust evidence to show that physical activity is associated with brain changes that lower the risk of Alzheimer’s. Can you give an example of an exemplar study in the field since then?
Erickson: There have been a few published last year. For example, a recent study by Rob Gons and colleagues showed that greater amounts of physical activity were associated with greater white matter integrity in a sample of 440 older adults in numerous brain regions. Such effects could be linked to better cognitive function and a reduced risk for dementia. Other examples include work by Larissa P. de Andrade et al., and Eric Vidoni et al.
CNS: What levels of physical activity are needed to cause these brain changes, based on the research available?
Erickson: Good question. We think that only modest intensity exercise is needed – but this probably needs to be regular for several months before significant effects accrue. However, we don’t have a good answer for this at this time.
CNS: How and why did you personally become interested in the link between exercise and cognition in the elderly?
Erickson: I was interested in how plastic the brain is throughout life and I saw the potential for exercise to influence the brain in several ways.
CNS: Are there any common misconceptions in the public about the link between exercise and brain health?
Erickson: I think the public often thinks that you need years of intense exercise to see effects, but you really don’t. Modest amounts are sufficient, and it is never too late to start.
CNS: What are some specific effects in the brain that you have seen in people who regularly exercise? What about for non-elderly versus elderly?
Erickson: We see changes happening in several brain circuits, including the hippocampus and prefrontal cortex. Most of these studies have been in older people, but studies in children and young adults suggest similar regions suggesting common pathways by which exercise influences the brain across the lifespan.
CNS: What are the most exciting areas for research in this area heading into the next decade?
Erickson: I think we will learn the extent to which exercise can be used as a treatment for Alzheimer’s disease and the extent to which it could help prevent or delay symptoms from occurring. In addition, we will probably learn much more about the mechanisms and limitations of exercise as well.