I wanted to be connected...

Sometime in 2007, a serpent of doubt slithered into my infoparadise. I began to notice that the Net was exerting a much stronger and broader influence over me than my old stand-alone PC ever had. It wasn’t just that I was spending so much time staring into a computer screen. It wasn’t just that so many of my habits and routines were changing as I became more accustomed to and dependent on the sites and services of the Net. The very way my brain worked seemed to be changing. It was then that I began worrying about my inability to pay attention to one thing for more than a couple of minutes. At first I’d figured that the problem was a symptom of middle-age mind rot. But my brain, I realized, wasn’t just drifting. It was hungry. It was demanding to be fed the way the Net fed it—and the more it was fed, the hungrier it became. Even when I was away from my computer, I yearned to check e-mail, click links, do some Googling. I wanted to be connected. Just as Microsoft Word had turned me into a flesh-and-blood word processor, the Internet, I sensed, was turning me into something like a high-speed data-processing machine, a human HAL.
I missed my old brain.

(...)

“Neurons seem to ‘want’ to receive input,” explains Nancy Kanwisher of MIT’s McGovern Institute for Brain Research: “When their usual input disappears, they start responding to the next best thing.” Thanks to the ready adaptability of neurons, the senses of hearing and touch can grow sharper to mitigate the effects of the loss of sight. Similar alterations happen in the brains of people who go deaf: their other senses strengthen to help make up for the loss of hearing. The area in the brain that processes peripheral vision, for example, grows larger, enabling them to see what they once would have heard.

Tests on people who have lost arms or legs in accidents also reveal how extensively the brain can reorganize itself. The areas in the victims’ brains that had registered sensations in their lost limbs are quickly taken over by circuits that register sensations from other parts of their bodies. In studying a teenage boy who had lost his left arm in a car crash, the neurologist V. S. Ramachandran, who heads the Center for Brain and Cognition at the University of California at San Diego, discovered that when he had the young man close his eyes and then touched different parts of his face, the patient believed that it was his missing arm that was being touched. At one point, Ramachandran brushed a spot beneath the boy’s nose and asked, “Where do you feel that?” The boy replied, “On my left pinky. It tingles.” The boy’s brain map was in the process of being reorganized, the neurons redeployed for new uses. As a result of such experiments, it’s now believed that the sensations of a “phantom limb” felt by amputees are largely the result of neuroplastic changes in the brain.

Our expanding understanding of the brain’s adaptability has led to the development of new therapies for conditions that used to be considered untreatable. Doidge, in his 2007 book The Brain That Changes Itself, tells the story of a man named Michael Bernstein who suffered a severe stroke when he was fifty-four, damaging an area in the right half of his brain that regulated movement in the left side of his body. Through a traditional program of physical therapy, he recovered some of his motor skills, but his left hand remained crippled and he had to use a cane to walk. Until recently, that would have been the end of the story. But Bernstein enrolled in a program of experimental therapy, run at the University of Alabama by a pioneering neuroplasticity researcher named Edward Taub. For as many as eight hours a day, six days a week, Bernstein used his left hand and his left leg to perform routine tasks over and over again. One day he might wash the pane of a window. The next day he might trace the letters of the alphabet. The repeated actions were a means of coaxing his neurons and synapses to form new circuits that would take over the functions once carried out by the circuits in the damaged area in his brain. In a matter of weeks, he regained nearly all of the movement in his hand and his leg, allowing him to return to his everyday routines and throw away his cane. Many of Taub’s other patients have experienced similarly strong recoveries.

The shallows: what the Internet is doing to our brains
Nicholas Carr