Mozart's Brain+the Fighter Pilot

Chapter 1 Learn as much as possible about how your brain works. This is the most important factor in getting smart and staying smart. In order to do this, you don't have to become a neurologist or subscribe to scholarly journals on neuroscience (the study of the brain at every operating level ranging from everyday observable behavior to brain processes taking place at the level of chemicals and molecules). Here is a useful summary of the facts you should know. The adult human brain weighs about three pounds and consists of about 100 billion nerve cells or neurons along with an even greater number of non-neuronal cells called glia (in Greek, glia means "glue") interspersed among the neurons. The neurons are responsible for the communication of information throughout the brain. Especially important is the brain's outer wrinkled mantle, the cerebral cortex, which gives the brain the appearance of a gnarled walnut. The cerebral cortex contains about 30 billion neurons linked to one another by means of a million billion neuronal connections called synapses. As pointed out by Nobel Prize-winning neuroscientist Gerald Edelman, more than 32 million years would be required to count all of the synapses in the human brain at a counting rate of one synapse per second. And if we concentrate on the number of possible neuronal connections (circuits) within the brain, we get an even more astounding number: 10 followed by a million zeros. To put that number into some kind of perspective, consider that the number of particles in the known universe comes to only 10 followed by seventy-nine zeros. Finally, consider that the glia, which exceed the number of neurons by at least a power of 10, are also believed to be capable of communication. If this is true, then the number of possible brain states exceeds even our most extravagant projections. Any of the brain's 100 or so billion neurons can potentially communicate with any other via one or more linkages. Indeed, each neuron is no more than two or three degrees of separation from another. Linkages, once formed, are strengthened by repetition. At the behavioral level, this takes the form of habit. Each time you practice a piano piece or a golf swing (presuming you are doing it correctly), your performance improves. This corresponds at the neuronal level to the establishment and facilitation of neuronal circuits. The cerebral cortex consists of the outer gray matter of the cerebral hemispheres and the cerebellum, the two structures that contain most of the neurons in the brain. Less than a quarter inch in thickness, this thin rind (cortex in the original Latin means "rind"), includes some 85 percent of all brain tissue. An obvious feature of the cerebral cortex is its highly convoluted surface and wrinkled appearance. This wrinkling serves the purpose of increasing the surface area of this thin outer layer without a corresponding increase in volume and size (similar to wrinkling a handkerchief so that the larger surface area can be contained in the smaller confines of a wallet or small purse). While it's true that certain brain areas are specialized (such as the centers for processing sight, sound, touch, and other qualities and properties), the largest portion of the brain, the association cortex, is devoted to establishing networks and thereby linking everything together throughout the brain. As a result of this networking, you don't separately see, hear, taste, smell, and feel your breakfast bagel-you experience it as a unity. It's the association cortex that makes that possible. Figure B, on page 23, shows the association cortex. Notice that it makes up more than 90 percent of the brain. Figure A, on page 22, depicts the other major brain areas along with some of their specialized functions. Notice that the right and left hemispheres are specialized for different functions as depicted in Figure C, on page 24, and discussRestak, Richard is the author of 'Mozart's Brain+the Fighter Pilot' with ISBN 9780609604458 and ISBN 0609604457.