From "Cognitive Fitness" by Roderick Gilkey and Clint Kilts, Harvard Business Review (need subscription, you can preview the summary of the article on the order page):
…advances in neuroscience suggest that there is no reason why your brain at 60 can’t be as competent as it was at 25. That would not have been news to thinkers such as Socrates, Copernicus, and Galileo, who were all still at the peak of their intellectual powers in their sixties and seventies. Nor would it surprise business leaders such as Alan Greenspan, Warren Buffett, and Sumner Redstone. These icons and others like them have intuitively understood that the brain’s alertness is the result of what we call cognitive fitness—a state of optimized ability to reason, remember, learn, plan, and adapt that is enhanced by certain attitudes, lifestyle choices, and exercises. The more cognitively fit you are, the better you will be able to make decisions, solve problems, and deal with stress and change. Cognitive fitness will allow you to be more open to new ideas and alternative perspectives. It will give you the capacity to change your behaviors and forecast their outcomes in order to realize your goals. You can become the kind of person your company values most. Perhaps more important, you can delay senescence for years and even enjoy a second career.
The article goes on to suggest steps you can take to stay cognitively fit and discusses some implications of the brain research to learning. For example, the study of mirror neurons, which "aid the speed and accuracy of our perception by mentally simulating objects and actions in our environment," helps us understand how we can learn better through observation and indirect experience.
The authors encourage play at work because play "engages the prefrontal cortex…nourishing our highest-level cognitive functions – those related to incentive and reward processing, goal and skill representation, mental imagery, self-knowledge, and memory, just to name a few." They suggest playing games, such as bridge, chess, sudoku, solving challenging crossword puzzles, doing improvisation, reading funny books.
Searching for patterns is another way to maintain your cognitive fitness: "First and foremost, challenge your existing mind-set, enlarge it, and make it more complex." The authors encourage executives to "[l]isten to different viewpoints, read new kinds of articles and books, and visit places with a focused set of learning objectives."
Those who seek novelty and innovation through continuous learning benefit from neuroplasticity, the brain’s ability to change and enhance its performance. The article suggests learning a new language, musical instrument, or new technology.