VOA慢速英语- 了解被误解的青少年大脑 .docx

VOA慢速英语: 了解被误解的青少年大脑 1AwomannamedFrancesJensenisa.Shehasbeenstudyingthehumanbrainforalmostallofhercareer.Butevenshewasnotreadyforthejobofraisingtwoteenageboys.Whatmadethistasksodifficult?Tryingtofindoutwhyintelligentandresponsibleyoungpeoplestilldidstupidthings.So,DoctorJensondidwhatanyneuroscientistwoulddo:shestudiedyearsofresearchonthehumanbrain.Whatshefoundmightclearupsomemyths,ormisinformationaboutteenagers.Herfindingsmightalsoprovidehelpforparents,teachers.andanyonehopingtounderstandthecomplexmindofateenager.Myth1–Ateen'sbodyandbraingrowatthesamepaceWhenchildrenreach,theirbodieschange.Teenagersstarttolooklikeadults.Youmightthinkthattheirbrainsarealsobecomingmorelikeadultbrains.Nottrue,saysDr.Jensen.Thebrainisthelastorganinthebodytomature.Andittakesintothemid-20sforittocomplete.Dr.Jensensaysifonecomparesthebraintoapuzzle,theteenagebrainhasmanypuzzlepiecesstillnotinplace.Shesaystheteenbrainhasadifferentstructureandfromanadultbrain.Theteenagebrainisindeeddifferentintermsofitschemistryandstructure.It'sabout80percent-Isaythatloosely-ofthewaytheadultstructureandfunction.Dr.Jensenrecentlywroteabookonteenagersandtheirbrains.ThebookiscalledTheTeenageBrain:ANeuroscientist'sSurvivalGuidetoRaisingAdolescentsandYoungAdults.Init,sheexplainsthestrengthsandweaknessesofthebrainduringthistimeofdevelopment.Shesaystheconnections,orwiring,oftheteenbrainisbetterforlearningnewthingsthantheadultbrain.First,Dr.Jensenexplainshowthebrainworks.Shesaysweareabletolearnthroughsynapses-areaswherebraincellstalktoeachother.Thechemicalsforsynapsesarefoundinhighlevelsinchildren.Thentheydropalittleinteenagersanddropevenlowerinadults.Dr.Jensenexplainsthatthisiswhychildrenlearnthingslikelanguagessoeasily.Theproteinsandthechemicalsinvolvedinbuildingsynapsesforlearningareathigherlevels,very,veryhighlevelsinthechild,andalittlebitlessintheadolescentandthencomedowntosortofadultlevels,whichiswhyachildcanlearntwo,threelanguagesflawlesslyandateenagerisprettygood,notquiteasgoodasachild,butbetterthananadultintermsoftherateatwhichtheycanlearnandabsorbinformation.So,theteenagebrainhasanincreasedabilitytolearnbutitdoesnotyethavealltheconnectionstomakethatlearningpossible.Thisisonereasonwhyteenagerbehaviorisoftendifficulttounderstand.Dr.Jensencomparesthissituationtoadriverwhoisabletodrivebutwhodoesnotknowyethowtousebrakestostopthecar.Somepartsoftheteenagebrainaresimplynotyetconnected,sheexplains.Theseareasaretheonesforjudgment,makinggooddecisions,self-controlandempathy,ortheabilitytosharesomeoneelse'sfeelings.Myth2-TheteenagebrainisresilientAnothermythDr.Jensenputtotestishowteenagersareabletorecoverfromabadexperience–whatwecallbeingresilient.Attimes,shesays,theteenagebrainisresilient.Butinotherwaysitisnot.Thingslikestressanddrugandalcoholusecangiveteenslong-termproblems.Andwealwaysthought,'Ohtheyaresoresilient.'Well,theyareandtheyaren't.Youknow,therearecertainthingsthatcanaffectthemlife-long.Thesameamountoflikestressoralcoholorpot,anadultmaysailthroughit-forthesameexposure-butateenagerwillbearalong-termproblembasedonthat.Dr.Jensensaysdrugsandalcoholicdrinkscanhavemuchmoreseriouseffectsontheteenbrainthanonanadultbrain.Shesaysdrugsandalcoholcanespeciallyaffectateenager'sIntelligenceQuotient,orIQ.YourIQcanchangeupordownbetween13and17(yearsold).Wedon'tyetquiteknowwhatcanmakeanIQgoupordown,butonethingthatweknowdoesmakeIQsgodowniscertainlyexposuretocertaindrugs,forinstancechronicpotsmoking;themoreyousmoketheloweryourIQisgoingtogoduringthattimewindow.Myth3–TeenagersarelazyManystudieshaveshownthatsleepisimportantforlearningandmemory.Butmanyteens-bothboysandgirls-oftendon'tgetenoughsleep.Whenstayuplateatnightandwakeuplateinthemorning,parentsmaythinkitisbecausetheyarelazy.Thislackofaction,Dr.Jensenexplains,isanothermythaboutteenagers.Shesaysateen'sbiologicalclockissetdifferentlythananadult's.Abiologicalclockcontrolsthebody'swakingandsleepingprocesses.Sheexplainsthatthebrainreleasesahormonetomakeyousleepy.Anadultreleasesthatsleep-causinghormonearound8:30atnight.Butateenager'sbraindoesnotreleasethatchemicaluntilabout11atnight.Thisleadstoalaterbedtime,evenwhentheteenhastowakeupearlythenextmorning.Thisisanothermyth.Theirbiologicalclocksareabsolutelyprogramedtobe2to3hourslaterforthesleepstarttimeandwaketimethanadults.Andofcourse,wewakethemupat6:00inthemorning,whichisequivalenttoabout3:00inthemorningforanadult.It'sprobablynottheoptimaltimefortheirbrainstobeputinalearning.Dr.Jensensaysallthisnewinformationabouttheteenagebraincanhelpadultsdoabetterjobasteachersandparents.Sheadvisesadultstostayconnectedwithteenagersandtobemorepatientwiththem.Shesaysparentsshouldsharethiswiththeirchildren.Knowinghowtheirbrainsworkmayhelpthemgetthroughtheirteenyearsmorehappily.第5页 共5页第 5 页 共 5 页第 5 页 共 5 页第 5 页 共 5 页第 5 页 共 5 页第 5 页 共 5 页第 5 页 共 5 页第 5 页 共 5 页第 5 页 共 5 页第 5 页 共 5 页第 5 页 共 5 页