sparked by Dr. Firlic's notion of what the future will hold for the human brain, I set about looking for a more concrete treatise on Neuroplasticity, a revolutionary development in neurology, the controversial nature of which has delayed its mainstream acceptance until recently. Dr. Doidge, a Canadian psychiatrist and medical researcher, whose scorn for the neuroplastic doubters simmers within his text, considers Neuroplasticity not just an important tool in the human brain's toolbox, but perhaps the single most important driver in our success as a species.
Neuroplasticity is, in brief, the human brain's capacity to cope with damage. If a part of the brain is compromised beyond its ability to function, the tasks which have been historically handled by that part of the brain are relocated to another part of the brain healthy enough to execute those tasks. Though the precise mechanisms of how it accomplishes this are still being debated, countless experiments have proven that this is exactly what is happening. Simply put, Neuroplasticity explains how, for example, stroke victim's are able to re-learn how to walk and or talk. It explains how we recover at all from any injury to the brain. Neuroplasticity also goes some way to explaining why the blind, the deaf, etc., often report a heightening in their other senses. When a sense is lost, the region of the brain that processes those sensory signals ceases to have a function for there's no input to handle. The brain seems to recognize this and slowly, over time, re-wires that unused brain center as an auxiliary processor for another active sense. In other words, the blind may hear better because what was once their visual cortex has been re-wired to serve as a second auditory cortex, thereby increasing the total amount of the brain tasked to handle auditory signals.
Though Neuroplasticity is the main drive of Dr. Doidge's exciting book, Neuroplasticity itself can't be completely understood without an explanation of how the human brain learns. And this is the second major focus of The Brain That Changes Itself, a description of what Dr. Doidge calls neural mapping. From infancy, whenever we perform an action,a code is laid down in our brains; think computer program. If an organism had to re-learn how to perform an action every time it tried to do it, that organism would be dead within days. So survival is intrinsically linked to reacting quicker than the thing trying to prey upon you. The brain's way of learning how best to react is to remember how an action was performed, store that action as code, and use that code as a shortcut whenever that action is performed in the future. Try to walk for the first time and you have no idea what to do. Too many muscles have to move, too many commands have to be sent and organized, that coordination is impossible. But if our brains hold shortcuts for actions like taking a step, or groups of actions like running, then, over time, our performance improves because every time we perform the action, we strengthen the neural map, the shortcut, which has reduced a complex action to a reflex.
Dr. Doidge has penned a complex story, but one which is as fascinating as it is dense. The descriptions of the experiments proving Neuroplasticity are lively and engrossing, as are the cases which neurosurgeons are attempting to figure out ways to aid Neuroplasticity in the severely disabled. This is well-rounded and gripping discussion of Neuroscience, a must read for anyone even remotely curious about how we learn. (4/5 Stars)
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