Advice to “sleep on it” could be well founded, scientists say. After a good nights sleep a problem that couldnt be solved the night before can often appear more manageable, although the evidence until now has been anecdotal (傳聞的). But researchers at the University of Luebek in Germany have designed an experiment that shows a good nights sleep can improve insight (洞察力) and problem-solving.

“If you have some newly-got memories in your brain, sleep acts on these memories and restructures (重組結(jié)構(gòu)) them, so that after sleep the insight into problem which you could not solve before increases,” said Dr Jan Born , a neuroscientist (神經(jīng)科學(xué)家), at the university. To test the theory, they taught volunteers two simple rules to help them turn a series of numbers into a new order. There was also a third, hidden rule, which could help them increase their speed in solving the problem. The researchers divided the volunteers into two groups: half were allowed to sleep after the training while the rest were forced to stay awake. Dr Jan Born and his team noticed that the group that had slept after the training were twice as likely to figure out the third rule as the other group. “Sleep helped,” Born said in a telephone interview. “The important thing is that you have to have a memory representation in your brain of the problem you want to solve and then you sleep, so it can act on the problem.” But Born admitted that he and his team dont know how restructuring of memories occurs or what governs it. Pierre Maquet and Perrine Ruby of the University of Liege in Belgium said the experimental evidence supports the anecdotal suggestions that sleep can help develop creative thinking. Although the role of sleep in human creativity will still be a mystery, the research gives people good reason to fully respect their periods of sleep, they added.

1. The underlined phrase “sleep on it” in Paragraph 1 probably means “＿＿＿ ”.

A. to delay deciding something until the next day B. to go on sleeping without being disturbed

C. to get as much sleep as possible D. to have a good sleep

2. Jan Born and his team carried out the experiment through ＿＿＿ .

A. comparison B. interview C. survey D. imagination

3. It can be inferred from the passage that ＿＿＿ .

A. people should sleep as long as they have time B. sleep is the best way to solve hard problems

C. people have various periods of sleep D. people know how sleep reconstructs memories

4. What would be the best title for the passage?

A. How Sleep Works B. Sleep Helps Solve Problems

C. No Evidence, but Well Founded D. Borns Discovery on Sleep