Word: brained
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Dates: during 2000-2009
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...first discoveries of neuroplasticity came from studies of how changes in the messages the brain receives through the senses can alter its structure and function. When no transmissions arrive from the eyes in someone who has been blind from a young age, for instance, the visual cortex can learn to hear or feel or even support verbal memory. When signals from the skin or muscles bombard the motor cortex or the somatosensory cortex (which processes touch), the brain expands the area that is wired to move, say, the fingers. In this sense, the very structure of our brain--the relative...
...DECADES, THE PREVAILING DOGMA IN neuroscience was that the adult human brain is essentially immutable, hardwired, fixed in form and function, so that by the time we reach adulthood we are pretty much stuck with what we have. Yes, it can create (and lose) synapses, the connections between neurons that encode memories and learning. And it can suffer injury and degeneration. But this view held that if genes and development dictate that one cluster of neurons will process signals from the eye and another cluster will move the fingers of the right hand, then they'll do that and nothing...
...doctrine of the unchanging human brain has had profound ramifications. For one thing, it lowered expectations about the value of rehabilitation for adults who had suffered brain damage from a stroke or about the possibility of fixing the pathological wiring that underlies psychiatric diseases. And it implied that other brain-based fixities, such as the happiness set point that, according to a growing body of research, a person returns to after the deepest tragedy or the greatest joy, are nearly unalterable...
...research in the past few years has overthrown the dogma. In its place has come the realization that the adult brain retains impressive powers of "neuroplasticity"--the ability to change its structure and function in response to experience. These aren't minor tweaks either. Something as basic as the function of the visual or auditory cortex can change as a result of a person's experience of becoming deaf or blind at a young age. Even when the brain suffers a trauma late in life, it can rezone itself like a city in a frenzy of urban renewal...
...EXTREME EXAMPLE OF HOW CHANGES IN the input reaching the brain can alter its structure is the silence that falls over the somatosensory cortex after its owner has lost a limb. Soon after a car crash took Victor Quintero's left arm from just above the elbow, he told neuroscientist V.S. Ramachandran of the University of California at San Diego that he could still feel the missing arm. Ramachandran decided to investigate. He had Victor sit still with his eyes closed and lightly brushed the teenager's left cheek with a cotton swab...