A team of US scientists have discovered that the adult brain is far more plastic and adaptable than thought previously. Using a pioneering technique Professor Karel Svoboda and colleagues from Cold Spring Harbor Laboratory in New York City studied the brain activity of living mice. The scientists firstly used genetic engineering to create mice with brain cells that produced a fluorescent green protein. They then placed a “window” over a part of the brain they wanted to study called the barrel cortex, which receives information that mice gather via their whiskers. The team then watched the adult brain cells for a month, observing the cells forming new connections and getting rid of old ones. In order to determine whether sensory input played a role in these changes, the scientists cut every other of the animals’ whiskers and then let them explore an unfamiliar environment. Results showed that the brain connections changed much more quickly after the whiskers were cut. Thus, suggesting that the adult brain can “re-wire” itself to a certain degree, in order to adapt to changes in sensory stimuli. Svoboad, suspects that brain cells develop connections to each other randomly, and that those that prove useful grow bigger and stronger, while those that have little use die off.
SOURCE/REFERENCE: Nature 2002; 420: 788-794