CriticalPeriodHypothesis

　　Thecriticalperiodforlanguageacquisition语言获得的关键期EricLennebergwasamajorproponent.

　　Thecriticalperiodhypothesis关键期假设

　　Itreferstoaperiodinone’slifeextendingfromaboutagetwotopuberty,duringwhichthehumanbrainismostreadytoacquireaparticularlanguageandlanguagelearningcanproceedeasily,swiftly,andwithoutexplicitinstruction.Itcoincideswiththeprocessofbrainlateralization.Priortothisperiod,bothhemispheresareinvolvedtosomeextentinlanguageandonecantakeoveriftheotherisdamaged

　　.「语言学习关键期」（thecriticalperiod）的争议.

　　认同「愈早开始学习外语,成效愈好」的人,在学理上常引用「语言学习关键期假说」（TheCriticalPeriodHypothesis）来论证此项观点.1959年,神经生理学家Penfield和Roberts从大脑可塑性的角度,提出十岁以前,是学习语言的最佳年龄.哈佛大学心理学教授DavidLenneberg（1967）则从医学临床经验,以「神经生理学的观点」有系统地解释「语言学习关键期」,他认为人的大脑从二岁开始边化（lateralization）[4],在边化完成前,人是用全脑来学习语言,约在青春期左右,大脑会完成边化,从此,语言学习主要由左边大脑负责.人脑「边化」后的语言学习不如全脑学习时期来得好.因此,语言学习最好在大脑完成边化之前,这也就是所谓的「语言学习关键期」.除了Lenneberg外,Bickerton（1981）和Coppieters（1987）的研究结果也倾向支持「语言学习关键期」的存在.Lenneberg提出「语言学习关键期假说」主要用来解释第一语（母语）的学习.而ThomasScovel（1969）更将此假说的解释范围扩及第一语以外的语言学习.

　　acculturation

　　n.文化传入,文化适应

　　Acculturationistheobtainmentofculturebyanindividualoragroupofpeople.Thetermoriginallyappliedonlytotheprocessconcerningaforeignculture,fromtheacculturingoracculturedrecipientpointofview,havingthisforeigncultureaddedandmixedwiththatofhisorheralreadyexistingoneacquiredsincebirth.

　　However,thetermnowhascometomean,inaddition,thechild-acquisitionacculturationofnativeculturesinceinfancyinthehousehold.Achild'slearningofitsfirstcultureisalsocalledenculturationormerelysocialization.

　　Thetraditionaldefinitionsometimesdifferentiatebetweenacculturationbyanindividual(transculturation)andthatbyagroup,usuallyverylarge(acculturation).

　　Theoldandthenewadditionaldefinitionshaveaboundarythatblursinmodernmulticulturalsocieties,whereachildofanimmigrantfamilymightbeencouragedtoacculturateboththedominantalsowellastheancestralculture,eitherofwhichmaybeconsidered"foreign",butinfact,theyarebothintegralpartsofthechild'sdevelopment.