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  3. Ah, blissful sleep, when we leave our daily toils behind and slip into mindless repose. Or do we? (46)Two reports in Science, on

Ah, blissful sleep, when we leave our daily toils behind and slip into mindless repose. Or do we? (46)Two reports in Science, on

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问题     Ah, blissful sleep, when we leave our daily toils behind and slip into mindless repose. Or do we? (46)Two reports in Science, one involving rats and the other humans, suggest that during sleep our brains remain quite busy, furiously consolidating important memories that have accumulated during the day.
    In the rat experiments, Matthew A. Wilson of the Massachusetts Institute of Technology and Bruce L. McNaughton of the University of Arizona inserted electrodes into the hippocampus, a region of the brain thought to be involved in spatial memory. As the rats learned to navigate a maze, their neurons fired in certain patterns corresponding to specific parts of the maze.
    (47)For several nights after the rats’ maze exercises, their hippocampal neurons displayed similar firing patterns; the rats were apparently playing back their memories of running the maze. The major difference was that the firing was more rapid, as if the memories were being run fast-forward. (48)The firing occurred during slow-wave sleep, a phase of deep (but not dreamless) sleep marked by low-frequency pulses of electrical activity in certain regions of the brain.
    The studies of humans were undertaken at the Weizmann Institute of Science in Israel. A team led by Avi Karni and Dov Sagi trained volunteers to recognize rapidly the orientation of symbols hidden in images flashed at the periphery of their vision. The workers had previously noted improvements in performance over a 10-hour period following a training session.
    To determine whether sleep played a role in this phenomenon, Karni and Sagi disrupted the sleep of volunteers after they had had their training session. Interfering with the subjects’ slow-wave sleep had no significant effect. (49)But an equivalent disruption of REM sleepy which is marked by rapid eye movements (hence its name) and vivid dreaming, kept the subjects from improving overnight.
    "These results indicate that a process of human memory consolidation, active during sleep, is strongly dependent on REM sleep," the group states. The experiments lend support to a theory advanced by Jonathan "practice sessions" in which animals hone survival skills.
    Why did Karni and Sagi detect memory consolidation during REM sleep and Wilson and McNaughton only during slow-wave sleep? (50)The answer seems to be that each group studied a different type of memory, one involving a highly repetitious task and the other the recollection of a place.
    Of course, hucksters have long asserted that people can learn new languages and other skills by listening to tapes while asleep. Wilson says he has been inundated with queries from people wanting to know if these claims are true. He responds that his research applies only to memories originally laid down during waking hours.

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答案这种激活发生在慢波睡眠期间。慢波睡眠是在大脑的某些区域中一个以电活动低频脉冲为标志的深层的(而非无梦的)睡眠的阶段。
解析 译文中采用分译法，将同位语译成了一个独立的句子。并且将后置定语"marked by..."调整到了所修饰的名词之前。
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