求语言学两个名词的解释!Critical Period HypothesisAcculturation在加一个 Perf

Critical Period Hypothesis
The critical period for language acquisition语言获得的关键期 Eric Lenneberg was a major proponent.
The critical period hypothesis关键期假设
It refers to a period in one’s life extending from about age two to puberty,during which the human brain is most ready to acquire a particular language and language learning can proceed easily,swiftly,and without explicit instruction.It coincides with the process of brain lateralization.Prior to this period,both hemispheres are involved to some extent in language and one can take over if the other is damaged
.「语言学习关键期」（the critical period）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」（The Critical Period Hypothesis）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David Lenneberg（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Thomas Scovel（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
Acculturation is the obtainment of culture by an individual or a group of people.The term originally applied only to the process concerning a foreign culture,from the acculturing or accultured recipient point of view,having this foreign culture added and mixed with that of his or her already existing one acquired since birth.
However,the term now has come to mean,in addition,the child-acquisition acculturation of native culture since infancy in the household.A child's learning of its first culture is also called enculturation or merely socialization.
The traditional definition sometimes differentiate between acculturation by an individual (transculturation) and that by a group,usually very large (acculturation).
The old and the new additional definitions have a boundary that blurs in modern multicultural societies,where a child of an immigrant family might be encouraged to acculturate both the dominant also well as the ancestral culture,either of which may be considered "foreign",but in fact,they are both integral parts of the child's development.