The Brain Most Active Dering Sleep For many years, people believed that the brain, like the body, rested during sleep. After

admin2013-05-04  36

问题                     The Brain Most Active Dering Sleep
    For many years, people believed that the brain, like the body, rested during sleep. After all, we are rendered unconscious by sleep. Perhaps, it was thought, the brain just needs to stop thinking for a few hours every day. Wrong. During sleep, our brain—the organ that directs us to sleep—is itself extraordinarily active. And much of that activity helps the brain to learn, to remember and to make connections.
    It wasn’t so long ago that the regretful joke in research circles was that everyone knew sleep had something to do with memory except for the people who study sleep and the people who study memory. Then, in 1994, Israeli researchers reported that the average performance for a group of people on a memory test improved when the test was repeated after a break of many hours during which some subjects slept and others did not. In 2000, a Harvard team demonstrated that this improvement occurred only during sleep.
    There are several different types of memory—including declarative (fact-based information) , episodic (events from your life) and procedural (how to do something)—and researchers have designed ways to test each of them. In almost every case, whether the test involves remembering pairs of words, tapping numbered keys in a certain order or figuring out the rules in a weather-prediction game, "sleeping on it" after first learning the task improves performance. It’s as if our brains squeeze in some extra practice time while we’re asleep.
    This isn’t to say that we can’t form memories when we’re awake. If someone tells you his name, you don’t need to fall asleep to remember it. But sleep will make it more likely that you do. Sleep-deprivation experiments have shown that a tired brain has a difficult time capturing memories of all sorts. Interestingly, sleep deprivation is more likely to cause us to forget information associated with positive emotion than information linked to negative emotion. This could explain, at least in part, why sleep deprivation can trigger depression in some people: memories stained with negative emotions are more likely than positive ones to "stick" in the sleep-deprived brain.
    Sleep also seems to be the time when the brain’s two memory systems—the hippocampus and the neocortex— "talk" with one other. Experiences that become memories are laid down first in the hippocampus, eliminating whatever is underneath. If a memory is to be retained, it must be shipped from the hippocampus to a place where it will endure the neocortex, the wrinkled outer layer of the brain where higher thinking takes place. Unlike the hippocampus, the neocortex is a master at weaving the old with the new. And partly because it keeps incoming information at bay, sleep is the best time for the "undistracted" hippocampus to shuttle memories to the neocortex, and for the neocortex to link them to related memories.
What is TRUE about the report of Israeli researches and the demonstration of a Harvard team?

选项 A、They proved that sleep had nothing to do with memory.
B、Their conclusions were different.
C、They were products of coordinated experiments.
D、They both proved that sleep helps remember.

答案B

解析 推理判断题。根据题干中的Israeli researchers和a Harvard team定位到第二段第二、三句。第二句说:报告指出在数小时后重复进行的记忆测试中,被测者的平均成绩有所提高,在这数个小时当中,有的被测者睡觉了,有的没有;第三句说:哈佛大学的研究团队证明这种成绩的提高只发生在睡眠时间内。由此可见,以上结论是不一样的,故[B]正确。两个试验的中间隔了6年,所以它们不可能是协调一致的,故排除[C];哈佛大学的研究证明了睡眠对记忆有帮助,故排除[A];但是以色列研究人员的报告并不能说明是睡过觉的人还是未睡过觉的人第二次测试的成绩有所提高,故不能证明睡眠是否对记忆有所帮助,故排除[D]。
转载请注明原文地址:https://kaotiyun.com/show/aCd4777K
0

最新回复(0)