From the University of California, Berkeley Wellness Letter, December 2012:
To boost your brain power, do tai chi. So suggests a study in the Journal of Alzheimer's Disease, which included 120 healthy older people in China.
Those who practice this "moving meditation" techniques three times a week for 40 weeks shows increases in brain volume, as seen on MRI, as well as improvements on several tests of memory and learning, compared to those not doing the exercise who had normal age-related brain shrinkage.
Previous research has shown that aerobic activity is good for the brain, but this study suggests that a more gentle form of exercise is also beneficial.
Another benefit of tai chi: it improves balance and decreases the risk of falls.
The International Taoist Tai Chi Society can help you find instructors and classes in your area.
For those who can't easily make it to class: consider using a DVD at home. E-mail me for some suggestions.