英語聽力文摘 藥物與學(xué)習(xí)能力
When you experience something new, do you know what happens to your brain?
Some of the neurons in your brain build new connections. The brain is rewired, as scientists often put it. Our brains are always changing, in response to new experiences or as a result of learning new information. That’s how we’re able to learn and remember new experiences and information.
However, the brain reacts quite differently when a person is exposed to drugs such as cocaine.
Evidence indicates that prior use of some drugs impairs the brain’s ability to forge new connections between neurons in response to new experiences. Scientists took a bunch of rats and gave some of them either amphetamine or cocaine for twenty days, while giving the others a saline solution for twenty days.
When the twenty days were up, half of the rats were moved from ordinary laboratory cages to fancy new cages equipped with all kinds of bridges, ramps, tunnels, and other toys. After three and half months the scientists examined all of the rats brains.
They discovered that the saline solution rats that were moved to the new cages had a greater number of neuronal connections than all the other rats, including the drugged rats in the new cages. These findings may aid in explaining some of the behavioral and cognitive impairments viewed in people who are addicted to drugs.
