If you were to count all the synapses in your brain, pointed out Nobel-prizing winning neuroscientist Gerald Edelman, it would take more than 32 million years.

The number of possible neuronal circuits in your brain is even more astonishing:

10 followed by 1,000,000 zeros.

To put this into context, the number of particles in the known universe is 10 followed by 79 zeros.

Ironically, despite this enormous potential, many people not only discount the power of their brain, but they fail to keep it in shape.

The myth that the amount of intelligence you have developed as an adult is somehow fixed has long been discounted in science. Research now shows that the brain is plastic.

Just as when you exercise, you develop more muscle fibers, so, too, when you use your brain more, you develop more neuronal circuits.

When you learn something new, your brain changes. New connections are formed. As you learn more and more about a subject, the thicker these connections, until you have a trunk line and some level of mastery on that subject. However, when you discontinue learning about that subject, those connections atrophy.

This is why an adult may know a lot less about a certain subject than someone in High School, even if they had studied the same thing. The brain of the High School student is developing connections, while the adult brain is atrophying them.

Physical fitness is something you notice right away. You know when you are out of shape. You can see it, feel it, sensate it. With the brain, it is more subtle. You have a tendency to forget more often. You are only interested in simple books and programs because you find comprehension a challenge. You think learning new things is boring. All these are symptoms of an out-of-shape brain.

It is not necessary to be older either to have an out-of-shape brain. Many people in their twenties, fed on a diet of superficial conversations, undemanding media exposure, and a disdain for any intellectual pursuit, show all the symptoms of inefficient brain functioning.

Age is often used as an excuse to neglect your brain. Again, another myth is responsible for it. The myth is that your brain is in a gradual state of atrophy. Your brain cells like your physical cells are aging rapidly. Actually, even if this were true, there is such an abundance of brain cells that it should not even make any noticeable difference.

The brain is plastic and it grows with use. The older you are, the more chances are that you have built a significant neuronet of ideas. It is actually possible to grow smarter as you grow older because you have more associations built up in your brain and therefore it is easier to grasp something. You don't have to start from scratch. You have internal references in place already.

Even after a neuronet on any subject has atrophied due to neglect, it can quickly be restored. Just as muscle-memory allows an out-of-shape athlete to get back into shape with exercise, so too does restudying your favorite subject quickly make you an expert at it again.

The most powerful youthing formula is doing mental exercises. Studies have shown that those seniors who play chess, card games, solve puzzles, or pursue an interesting hobby, not only have a great attitude, but they are also biologically younger than others of the same chronological age.

The idea that you get dumber as you grow older, it is just not true. Those who are considered "knowledge workers" are as sharp in their older years, then when they were younger. Einstein, for example, was still working out problems in Physics on the day he died.

In some older cultures, wise men are portrayed as old. They are imagined with long white hair and long white beards. In those cultures they understand that an older person has had more time to learn more things.

In Western cultures, older people are portrayed as senile. They are tolerated, rather than respected. This new archetype is a destructive one. Those who embrace it, even unconsciously, come to live it out.

Senility is a condition of atrophy due to brain neglect. This neglect eventually results in some form of physical manifestation, a variety of organic damage and dementia.

Senility is not a symptom of old age, but a symptom of prolonged neglect.

Getting your brain in shape is a lot easier and faster than getting your body in shape. Your brain does not tire and it grows fitter faster.

It is not possible to lead a full, significant, and happy life if you are in poor mental shape.

The good news is that all it takes to become an interesting, vibrant, and progressive person is to start to exercise your brain.