An in-depth review of 4,600 clinical trials -- led by researchers at the Berenson-Allen Center for Noninvasive Brain Stimulation at Beth Israel Deaconess Medical Center (BIDMC) published last May, provided further insight into what we already know; that staying active is vital for maintaining optimal health as we age. However, this latest study was undertaken explicitly to more clearly define the amount of exercise that contributes to better brain health in older adults, as well as those with dementia. The researchers were not surprised that regular exercise contributes to overall brain health, but they were intrigued by the fact that individuals (older adults and those with mild cognitive impairment) who exercised for at least 52 hours over a period of six months were the ones who enjoyed enhanced improvements in mental processing speed. The study concluded that it is the cumulative effect of exercise that is most significant, not necessarily the number of hours exercised per week. The researchers also found that nearly any type of physical activity -- walking, running, cycling, weight-lifting as well as more mindful exercise, such as yoga and tai chi, all contributed to improved cognitive performance.

So if you start an exercise regimen -- stick with it -- and keep your brain functioning in top form.

What else can you do to improve brain function? Quite a few things, according to experts.

Sandra Bond Chapman, Ph.D., founder and chief director of the Center for BrainHealth at the University of Texas at Dallas and author of Make Your Brain Smarter has some great ideas. She addressed the issues of preserving and improving the brain's capacity in an interview I conducted for my book Kensho: A Modern Awakening. Chapman is quick to point out that our life expectancy is longer than ever before. We rarely pay enough attention to maintaining brain health. The good news is that there is hope for us all. Chapman says that when you develop new interests, pursue hobbies or perform specific brain exercises, you enhance your brain's ability to become more proficient, and at the same time, expand memory. The science of neuroplasticity confirms this rule -- so try new things to help your brain make new connections. Simply put, you have considerable control over your brain function since much depends on what you experience, and how you use your brain.

"Neglecting your cognitive health and allowing your brain to lose its mental edge with routine activities -- rather than innovative thinking -- has unnecessary and deleterious economic, social and personal ramifications. The longer we are living, the more competitive the marketplace becomes, the more complex our social fabric grows, the more imperative it becomes that we leverage our most precious resource, our brain," maintains Chapman.

In our always-on connected society, more and more people express information overload, and have concerns about feeling mentally exhausted. Many of us conclude that we need a vacation or some downtime, when the actual remedy required is a boost in brain health. Signs that you need to take a closer look at your brain health, according to Chapman's research, include a recurring feeling of mental fatigue or low mental energy, increased instances of forgetfulness, difficulty making decisions, the feeling that you're overwhelmed by information and the inability to plan or create innovative solutions.

Often, these symptoms are reversible. What can help here, Chapman says, is to reduce toxic brain habits and make the conscious decision to adopt a more brain-fit lifestyle.

Over and above regular exercise, Chapman offers the following brain-boosting advice:

1. Limit multitasking.

Chapman strongly suggests that we should all stop multi-tasking, stat. Multitasking diminishes mental productivity, elevates brain fatigue and increases stress. Focusing on several things at once puts a strain on the brain and can have an adverse effect on your memory. Try to block out unimportant information and remain laser-focused. Chapman reveals that multitasking is "as toxic to the brain as smoking is to the lungs," and can even break down the immune system.

2. Get an adequate amount of sleep.

Make sure you regularly get seven-to-eight hours of sleep. Information is consolidated in the brain at a deeper level of understanding during sleep, and its restorative action cleanses your brain of some of the toxicity that has built up from stress or worry. "Without good sleep, we see increased anxiety and stress. Sleep is restorative, helping you be more mentally energetic and productive," advises Chapman.

3. Construct bottom-line messages.

Summarize your task-assignment reading, training seminars, articles, movies or TV shows you see, or books you read. Abstracting novel ideas, versus remembering a litany of facts, builds a brain with an enhanced long-term memory for global ideas and the ability to retrieve fundamental facts. As well, hypothesizing with a friend about what's happened (or coming up) in your favorite book or TV series contributes to deeper thinking, thereby fortifying your neural connections. Chapman likens deeper-level thinking to "push-ups and sit-ups for the brain."

4. Stay motivated.

A motivated brain builds faster and more robust neural connections. Identify your passions and learn more about them. Once you have mastered a particular aspect, try something more challenging.

5. Socialize to stay sharp.

Socializing and maintaining friendships can protect against cognitive decline. "One of the most powerful things for brain health is relating to others -- a shared sense of community is one of the top three factors associated with brain health as we age," Dr. Chapman says. Interestingly, it's not the number of friends you have, she says, but rather the quality and depth of your connections that is significant.