考研英语阅读例题：Howsiestashelpmemory午睡怎样增进记忆力.doc

How siestas help memory 午睡怎样增进记忆力[2010.02.25] The Economist MAD dogs and Englishmen, so the song has it, go out in the midday sun. And the business practices of England’s lineal descendant, America, will have you in the office from nine in the morning to five in the evening, if not longer. Much of the world, though, prefers to take a siesta. And research presented to the AAAS meeting in San Diego suggests it may be right to do so. It has already been established that those who siesta are less likely to die of heart disease. Now, Matthew Walker and his colleagues at the University of California, Berkeley, have found that they probably have better memory, too. A post-prandial snooze, Dr Walker has discovered, sets the brain up for learning.The role of sleep in consolidating memories that have already been created has been understood for some time. Dr Walker has been trying to extend this understanding by looking at sleep’s role in preparing the brain for the formation of memories in the first place. He was particularly interested in a type of memory called episodic memory, which relates to specific events, places and times. This contrasts with procedural memory, of the skills required to perform some sort of mechanical task, such as driving. The theory he and his team wanted to test was that the ability to form new episodic memories deteriorates with accrued wakefulness, and that sleep thus restores the brain’s capacity for efficient learning.They asked a group of 39 people to take part in two learning sessions, one at noon and one at 6pm. On each occasion the participants tried to memorise and recall 100 combinations of pictures and names. After the first session they were assigned randomly to either a control group, which remained awake, or a nap group, which had 100 minutes of monitored sleep.Those who remained awake throughout the day became worse at learning. Those who napped, by contrast, actually improved their capacity to learn, doing better in the