Source: Kirk I. Erickson, Michelle W. Voss, Ruchika Shaurya Prakash, Chandramallika Basak, Amanda Szabo, Laura Chaddock, Jennifer S. Kim, Susie Heo, Heloisa Alves, Siobhan M. White, Thomas R. Wojcicki, Emily Mailey, Victoria J. Vieira, Stephen A. Martin, Brandt D. Pence, Jeffrey A. Woods, Edward Mcauley, and Arthur F. Kramer. Exercise training increases size of hippocampus and improves memory. PNAS, Jan. 31, 2011.
It should be no surprise that this recent study is based on participation in some type of moderate physical exercise. More and more studies are being conducted that give credence to the fact that exercise is beneficial to our health and well-being. A new study shows that one year of moderate physical exercise can increase the size of the hippocampus in older adults, which leads to an improvement in spatial memory.The hippocampus is a major component of the human brain as well as other mammals. It is part of the limbic system and plays an important role in long-term memory and spatial navigation. For those who suffer from Alzheimer's disease, it is one of the first areas of the brain that suffers damage. Some of the results of this damage include memory problems and disorientation. People who have extensive bilateral hippocampal damage are known to experience a form of amnesia, the inability to retain or form new memories.
This particular study was conducted by researchers at the University of Pittsburgh, University of Illinois and Rice University at Ohio State University. It is the first study of its kind focused on older adults who are already suffering from atrophy of the hippocampus, the main brain structure associated with memory formation. The researchers took 120 elderly people who did not have dementia, and placed them into two separate groups. One group was limited to doing only stretching and toning exercises while the other group began a regimen of walking around a track for forty minutes a day three days a week. All participants had initial magnetic resonance images taken before beginning the program, six months later and at the end of the one-year study.
The group that participated in the aerobic exercise activities showed an increase in volume of the right hippocampus of 1.97% and of the left hippocampus of 2.12%. The same areas of the brain for those who did only stretching exercise actually decreased in volume by 1.40% and 1.43%. Later, memory tests were conducted for all of the participants in three separate trials. Those in the aerobic group showed an improvement in memory function when compared to their performance at the beginning of the study. This improvement is directly associated with the increased size of the hippocampus. Researchers have noted that atrophy of the hippocampus as we age is almost certain, but are very excited about the fact that even a moderate amount of aerobic exercise for one year can help to increase the size of it. Researchers find these studies to be particularly promising because they suggest that even the most sedentary older adults that take on a moderate amount of exercise for one year can have substantial improvements in memory and brain health.