Sleeping on a problem really can help solve it, say scientists who found a dreamy nap boosts creative powers.

    They tested whether "incubating" a problem allowed a flash of insight, and found it did, especially when people entered a phase of sleep known as REM.

    Volunteers who had entered REM or rapid eye movement sleep - when most dreams occur - were then better able to solve a new problem with lateral thinking.

    Proceedings of the National Academy of Sciences has published the US work.

    In the morning of the test day, 77 volunteers were given a series of creative problems to solve and were told to mull over the problem until the afternoon either by resting but staying awake or by taking a nap monitored by the scientists.

    Compared with quiet rest and non-REM sleep, REM sleep increased the chances of success on the problem-solving task.

    The study at the University of California San Diego showed that the volunteers who entered REM during sleep improved their creative problem solving ability by almost 40%.

    The findings suggest it is not merely sleep itself, or the passage of time, that is important for the problem solving, but the quality of sleep.

    Lead researcher Professor Sara Mednick said: "We found that, for creative problems you've already been working on, the passage of time is enough to find solutions.

    "However for new problems, only REM sleep enhances creativity."

    The researchers believe REM sleep allows the brain to form new nerve connections without the interference of other thought pathways that occur when we are awake or in non-dream-state sleep.

    "We propose that REM sleep is important for assimilating new information into past experience to create a richer network of associations for future use," they told PNAS.

    Dr Malcolm von Schantz of the Surrey Sleep Research Centre at the University of Surrey said: "Whatever the importance of the dreams themselves are, this paper confirms the importance of REM sleep, the sleep stage when most of our dreaming takes place."

    他們測(cè)試"孵化"一個(gè)問題能否使靈光乍現(xiàn)，結(jié)果表示是能夠的，特別是當(dāng)我們進(jìn)入一個(gè)稱為REM的睡眠階段。

    參與實(shí)驗(yàn)的志愿者進(jìn)入較多夢(mèng)的REM階段，或快速眼動(dòng)期（rapid eye movement sleep）,都較能以水平思考解決新的問題。

    《國(guó)家科學(xué)研究院學(xué)報(bào)》（Proceedings of the National Academy of Sciences/PNAS）刊登美國(guó)這項(xiàng)研究。

    在測(cè)試當(dāng)天的早上，77名志愿者給派發(fā)一連串創(chuàng)意問題，并需要仔細(xì)思考問題直至下午，然后選擇保持清醒地休息，或是小睡，由科學(xué)家觀察情況。

    與靜靜地休息及沒快速眼動(dòng)睡眠相比，有快速眼動(dòng)期睡眠的人成功地解決問題的機(jī)會(huì)增加了。

    加州大學(xué)圣地亞哥分校進(jìn)行的這項(xiàng)研究顯示，志愿者睡覺時(shí)進(jìn)入快速眼動(dòng)期，解決問題的創(chuàng)意能力提升近四成。

    結(jié)果表示解決問題最重要的關(guān)鍵，不單是睡眠本身，或者睡眠時(shí)段，而是睡眠的質(zhì)素。

    首席研究員梅德里克（Sara Mednick）教授說(shuō)：「我們發(fā)現(xiàn)，對(duì)于思考中的創(chuàng)意問題，睡眠時(shí)段已能夠找出解決方法�！�

    「對(duì)于解決新的問題，只有快速眼動(dòng)期的睡眠，才可以提升創(chuàng)意能力�！�

    研究員相信在快速眼動(dòng)期睡眠期，大腦能不受其它思緒干擾，形成新的神經(jīng)網(wǎng)絡(luò)，那是在清醒或無(wú)夢(mèng)狀態(tài)睡眠時(shí)不能做到的。

    「新信息吸收后并融入過去經(jīng)驗(yàn)中，形成一個(gè)可將來(lái)使用的豐富聯(lián)想網(wǎng)絡(luò)，在這方面，我們認(rèn)為快速眼動(dòng)期扮演重要角色。」他們向《國(guó)家科學(xué)研究院學(xué)報(bào)》說(shuō)。

    Surrey大學(xué)Surrey睡眠研究中心的Malcolm von Schantz博士說(shuō)：「無(wú)論夢(mèng)境本身有何重要，這份研究證實(shí)了快速眼動(dòng)期睡眠的重要，這是睡眠中大多夢(mèng)境出現(xiàn)的時(shí)候。」