Getting-Enough-Sleep-Dream-on

GettingEnoughSleep?DreamonIseighthours'sleepenoughtoeveryone?Haveyoueverheardofsleepdebt?Thefollowingarticlewarnsusoftheconsequencesofsleepdeprivationandsuggestswaystoworkoffsleepdebt.八小时的睡眠是不是对每个人都充裕？你听说过“睡眠债”吗？下面这篇文章提醒我们睡眠不足的后果，建议我们如何偿还睡眠债。Ioncehadapatientwhowassosleep-deprivedthatsheloadedherdirtydishesintotheclothesdryerinsteadofthedishwasher.Sheturnedonthemachine,smashingchinaandglasses.我曾经有过一位病人，她由于睡眠严重不足，竟把脏碟子放进了干衣机，而不是放进洗碗机里面。她扭开干衣机的开关，哗啦啦，瓷器和玻璃器皿撞成了碎片。Anotherpatientwenttogreatlengthstoobtaina50-yard-linetickettoacrucialSanFrancisco49ersplay-offgame,butwassosleepythathedozedoffinhisseatinthefirstquarterandstayedasleepuntilthegamewasover.还有一位病人费了九牛二虎之力才弄到一张五十码线门票，观看旧金山49淘金人协会举行的一场至为关键的加时赛，但他实在太疲倦了，头一段比赛就在座位上睡着了，一直睡到比赛结束才醒。Onaneverydaylevel,sleepypeoplemakematherrors,breakthingsandbecomecrosswiththeirfamilies,friendsandco-workers.Lesscommonly,theymakemistakeswithtragicconsequences.Itishardtoprovehowmanyfatalcaraccidentsarecausedbythedriver'sfallingasleep,butmyconvictionisthatthenumberishigh.Laboratoryexperimentshaveconfirmedthatthesleep-deprivedmindispronetomicrosleeps－lapsesofconsciousnesssobriefthatthesubjectmaynotevenbeawareofthem.几乎每天，打瞌睡的人会犯数学错误，打坏东西，或向家人、朋友和同事发火。瞌睡者因犯错而导致可悲后果的情况并不常见。很难证实，有多少起致命的车祸是由于驾驶员瞌睡引起的，但是，我相信，这个数目一定不小。实验室的试验已经证实，缺少睡眠的大脑很容易进入“短暂的昏睡”——阵发性的意识丧失，这种意识丧失的时间短得甚至连当事人都可能意识不到。InoneexperimentinourlaboratoryatStanfordUniversity,avolunteerwhohadonlybeenallowedfourhours'sleepthenightbeforehadhiseyelidstapedopen(uncomfortable,butitdoesn'thurt).Hewasaskedtopressabuttoneverytimeanirregularstrobelightflashed.Forafewminuteshetappedtheswitchaftereachflash,onaverageeverysixseconds.Thenabrightflashsurgedintohispupils－buthedidnothing.在斯坦福大学实验室进行的一项实验中，只让一名自愿者前一天晚上睡四个小时，然后把他的眼睑固定，让他睁着眼睛，（这样做虽不舒服，但并无损害）。按照要求，每当频闪闪光灯无规律地闪光之时，他必须揿下一个按钮。最初几分钟，每闪一次他揿一下按钮，平均每六秒钟一次。而后，一道强光照入他的眼球——但是，他一动没动。Whydidn'tyoupresstheswitchjustnow?weasked.Becausetherewasnoflash,theyoungmanreplied.Themachinesweusedtomonitorbrainactivityshowedthatattheverymomentthelighthadflashed,theyoungmanhadunwittinglyfallenasleep,withhiseyeswideopen,fortwoseconds.Ifhehadbeenbehindthewheelofacar,thosetwosecondscouldhavemeantdisaster.“刚才你为什么不揿按钮？”我们问他。“没有闪光啊?”年轻人回答说。监控大脑活动的机器表明，就在灯光闪烁的那一刻，这位年轻人已经睁着双眼不知不觉地睡着了，睡了两秒钟。倘若他当时是在开车，这两秒钟可能就意味着灾难。Societalpressurestoworkmoreandatoddhourshavereducedoursleeptimeoverthepastcenturybyabout20percent.Addtothemixourownera'sdrivetohaveanddoitall－work,family,sports,hobbies－andthereisverylittletimeleftforrest.Iconsidersleepdeprivationanationalemergency.上个世纪，迫于社会压力，我们不得不加班加点，睡眠时间减少了约20％。我们这个时代充满着各种欲望：工作，家庭，运动，业余爱好等等，使这种忙乱有增无减。因此，休息时间便所剩无几了。我认为睡眠缺失是国家的紧急情况。SleepDebtandtheMortgagedMind睡眠债与抵押的大脑Generally,adultsneedtosleeponehourforeverytwohoursawake,whichmeansthatmostneedabouteighthoursofsleepanight.Ofcourse,somepeopleneedmoreandsomeless.Childrenandteenagersneedanaverageofabouttenhours.Thebrainkeepsanexactaccountingofhowmuchsleepitisallowed.MycolleaguesandIcoinedthetermsleepdebtbecauseaccumulatedlostsleepislikeamonetarydebt:itmustbepaidback.Ifyougetanhourlessthanafullnight'ssleep,youcarryanhourofsleepdebtintothenextday－andyourtendencytofallasleepduringthedaytimebecomesstronger.一般说来，成人每清醒两小时就需要一小时的睡眠，这就意味着大多数人每晚需要八个小时的睡眠。当然，有人需要的多些，有人需要的少些。儿童和青少年平均需要十个小时的睡眠时间。大脑对应有的睡眠量做出准确的计算。我和同事们杜撰了“睡眠债”这个词--睡眠缺失积累下来，就像债务一样：必须得到偿还。倘若某个晚上少睡一小时，一小时的睡眠债就被带到第二天，白天越来越想睡觉。Duringafive-dayworkweek,ifyougotsixhoursofsleepeachnightinsteadoftheeightyouneeded,youwouldbuildupasleepdebtoftenhours(fivedaystimestwohours).Becausesleepdebtaccumulatesinadditivefashion,bydayfiveyourbrainwouldtendtowardsleepasstronglyasifyou'dstayedupallnight.Fromthisperspective,sleepinguntilnoononSaturdayisnotenoughtopaybackthetenlosthoursaswellasmeetyournightlyrequirementofeight;youwouldhavetosleepuntil5p.m.tobalancethesleepledger.Butformostpeopleitisdifficulttosleepthatlongbecauseofthealertingmechanismofourbiologicalclock.在每周五天的工作日里，倘若每晚只睡六小时，而不是所需的八小时，你就欠下了十个小时的睡眠债（5天×2小时）。由于睡眠债是以累积的方式攒下的，到了第五天，你的大脑会非常想睡觉，就好像你整夜未眠似的。从这个角度说，周六睡到中午并不能满足每晚八小时的睡眠需要，也不够偿还缺失的十小时睡眠；只有睡到下午5点才能保持这本睡眠帐的平衡。然而，对大多数人来说，由于我们生物钟的警醒机制，我们很难睡那么长的时间。WideAwakebutNotRested睡意全无却没有得到休息Anamazinglyprecisebiologicalclockwithinusregulatessleepingandwaking,andalsosynchronizesavastarrayofbiochemicaleventsinourbodies.Itisatimepieceofsuchastonishingprecisionthatpeopleoftenwakeupafewminutesbeforetheiralarmclocksgooff.我们体内的生物钟准确得简直令人叹服，我们何时睡眠，何时苏醒全由它调节，它还与我们体内的一系列生化活动保持同步。这种时钟准确得惊人，我们往往就在闹铃响前几分钟醒来。Mostpeoplehavetwopeaktimesofalertnessdaily,atabout9a.m.and9p.m.Alertnesswanestoitslowestpointataround3p.m.;afterthatitbeginstobuildagain.Thisexplainswhypeoplewhohaveworkedhardalldaywilloftenstarttofeelmorealertatthesametimeeveryeveningdespitealargeaccumulationofsleepdebtduringtheday.Ibelievethisclock-dependentalertingcanoftendeceivepeopleintothinkingtheyaresufficientlymeetingtheirsleepneeds.大多数人每天有两次警醒高峰，上午9点和晚上9点左右。警醒度在下午3点衰减至最低点，随后又开始攀高。这就是为什么那些整天努力工作，白天欠下一屁股睡眠债的人们，却常常在每晚的同一时间开始感到更加警醒。我认为，这种“依赖时钟型警醒”的情况常会使人产生错觉，以为自己的睡眠已经满足了需求。SomeyearsagoIhadthechancetoobserveastrikingexampleofclock-dependentalertinginaction.Itwasduringavis