Now that school has started， many parents find themselves struggling to shift their kids back to a working routine. As they shave off time for TV and the Internet to make way for schoolwork， parents may want to add extra for that other big contributor to success at school： sleep. Recent research on kids has connected the importance of sleep not only to cognition， but to behavior and mood as well.

    Some researchers theorize that the REM， or rapid eye movement， phase of sleep is when the brain produces and consolidates neural networks for memory and cognition. It's a kind of "formatting of the brain，" says Ralph Downey， an expert of sleep medicine at Loma Linda University and Children's Hospital in Southern California and a spokesperson for the American Academy of Sleep Medicine. Before the age of 6， a typical child will require between 12 and 13 hours of sleep per night， says Judith Owens， associate professor of pediatrics at Brown University and a noted expert on childhood sleep disorders. At age 6， 10 to 11 hours are needed. While the amount of sleep necessary drops once kids reach adolescence， Owens notes， "they still need at least nine hours under ideal circumstances."

    What if they come up short？ A sleep-deprived child's reaction is often different from the low energy and sleepiness experienced by adults. "Reducing the amount of hours a child sleeps manifests itself in the child becoming wired and hyperexcitable——exhibiting behavior similar to children with attention deficit disorder，" says David Gozal， director of the pediatric sleep program at the University of Louisville in Kentucky. Kids' emotions may become erratic， says Gozal， and they may be less apt to listen or pay attention. Researchers at the University of Montreal report that a study of young children showed that those who slept significantly fewer hours than the recommended 10 were more hyperactive and impulsive than those who got plenty of shuteye and scored lower on two cognitive skills tests.

    "Our results indicate that a modest but chronic reduction of just one hour of sleep nightly in early childhood can affect the child's cognitive performance at school entry，" says Dominique Petit， a sleep researcher and coauthor of the study. She thinks there's a critical period in early childhood when the lack of sleep is particularly detrimental to development， even if sleep habits improve later on.

    But moving "lights out" earlier can be a big challenge. Mark Goetting， a sleep medicine specialist and medical director of the Sleep Health Center in Portage， Mich.， offers some recommendations：

    Create positive associations with going to bed. "Often， parents will say to a child， 'You can stay up as long as you're good，' or， 'If you don't do what I say， you're going to bed.' It's not healthy to associate going to bed with punishment，" says Goetting. "Parents and children will begin to see bedtime as a power struggle." And， of course， both want to win.

    Establish a wind-down period before bed. A routine （like reading stories） can let a child know that he's headed toward bedtime and can help him slow down.

    Construct a bedroom environment that promotes sleep. "A bedroom should not be a terribly stimulating place，" says Goetting. So move the televisions， bright lights， and toys.

    When the kids sleep better， parents may notice a difference in their own quality of life， too. "Parents are definitely better rested themselves——their mood is better， they feel more alert——and are able to function better at home and at work，" says Owens. "It really sends a positive ripple through the entire family."

    （Agencies） 新學(xué)期開始了，很多家長正努力地把孩子拉回正軌。在讓看電視和上網(wǎng)讓位于家庭作業(yè)的同時，家長們可能還想為孩子的學(xué)習(xí)進(jìn)步再添一大“砝碼”――睡眠。近日一項有關(guān)兒童的研究發(fā)現(xiàn)，睡眠不僅和兒童的認(rèn)知表現(xiàn)有重要關(guān)系，而且會影響他們的行為和情緒。

    一些研究人員提出，大腦在快速動眼睡眠期會產(chǎn)生并鞏固形成記憶和認(rèn)知的神經(jīng)元。洛瑪？林達(dá)大學(xué)及南加州兒童醫(yī)院的睡眠藥物專家、美國睡眠藥物學(xué)會發(fā)言人拉爾夫？唐尼說，這有點像大腦的一種“格式化”。布朗大學(xué)兒科學(xué)副教授、兒童睡眠問題知名專家朱迪思？歐文斯說，一個正常的孩子在六歲之前每天需要12至13個小時的睡眠。6歲的孩子每天需要10至11個小時的睡眠。他說，盡管孩子到了青春期后所需的睡眠時間開始減少，“但在理想狀況下，他們?nèi)孕枰�至少九個小時的睡眠”。

    孩子睡眠不足會怎樣呢？孩子在睡眠不足時的反應(yīng)往往不同于成年人（在缺覺情況下）感到的精力不足與困乏�？纤�基州路易斯維爾大學(xué)的兒童睡眠研究主任大衛(wèi)？格扎爾說：“孩子在缺乏睡眠的情況下會變得很亢奮――他們此時的行為表現(xiàn)與多動癥兒童類似。” 格扎爾說，（在睡眠不足的情況下），孩子的情緒會變得反復(fù)無常，他們往往不聽話、注意力也不如平時集中。蒙特利爾大學(xué)的研究人員稱，一項有關(guān)幼童的研究表明，睡眠時間嚴(yán)重低于專家建議的10個小時的兒童比睡眠充足的兒童更加亢奮與沖動，他們在兩項認(rèn)知能力測試中的得分也較低。

    睡眠研究專家、該研究報告的撰寫者之一多明尼克？派提特說：“我們的研究結(jié)果表明，在幼童時期，每晚的睡眠時間哪怕只減少一個小時，長時間持續(xù)這種狀況都會影響孩子上學(xué)時的認(rèn)知表現(xiàn)。”她認(rèn)為，幼童時期中存在一個關(guān)鍵階段，在這一階段缺乏睡眠對孩子的成長尤為不利，即使他們今后的睡眠習(xí)慣有所改善也無法補(bǔ)救。

    但讓孩子早睡覺可謂一大難題。密歇根波蒂奇睡眠健康中心睡眠藥物專家、醫(yī)務(wù)主任馬克？格汀提出了以下建議：

    建立上床睡覺“積極聯(lián)系”。格汀說，“家長常對孩子說，‘只要你表現(xiàn)好，就可以晚睡會。’或者是，‘如果你不聽話，就給我滾到床上去。’將睡覺與懲罰聯(lián)系在一起是不健康的。家長與孩子都會將上床睡覺視為一種‘權(quán)威的爭奪’。”當(dāng)然，雙方都想贏。

    建立睡前“緩沖期”。（睡前講故事等）例行活動能讓孩子意識到自己該睡覺了，可以讓他安靜下來。

    為孩子營造一個能促進(jìn)睡眠的臥室環(huán)境。格汀說，“臥室環(huán)境不可有強(qiáng)烈的刺激效果。”所以，電視機(jī)、明亮的燈以及玩具等都應(yīng)該移出臥室。

    孩子睡得好，家長會發(fā)現(xiàn)自己的生活質(zhì)量也有所改觀。歐文斯說：“這樣一來，父母們就能更好地休息了――情緒變好了，反應(yīng)也更加敏捷――在家庭和工作中的表現(xiàn)就能更加出色了。這對于整個家庭來說的確是件好事。”