Critical Period Effects in Second Language Learning - Essay Example

Critical period hypothesis Introduction The critical period hypothesis is a prominent field of controversy and has been debated for a long time in the acquisition of language and linguistics, to the degree to which ability of language acquisition is linked to the age biologically. Beyond this period, acquisition of language becomes much more effortful and difficult. The critical period hypothesis states that the initial years of human life is very important as this is the time during which individuals acquire their first language. Critical period hypothesis further states that if input of the language fails to take place until this time passes, the individual may never achieve total command of the language, most specifically the grammatical system. However, that particular time has limited evidence, and largely support stems from analogies and arguments that are theoretical to other biological critical periods like visual development. The nature of the critical period phenomenon has however been debated fiercely in cognitive science and psycholinguistics for decades. This duration of critical period also varies greatly in different accounts. For instance, in acquisition of the second language, the greatest evidence for the critical period hypothesis is depicted in the accent study; in which majority of older learners never attain native like accent. Nevertheless, a few students have found that some adult L2 learners, in some conditions, have achieved native-like accent (Mark, 1980, p 25). This suggests that accent is majorly influenced by varying multiple factors such as motivation and identity, and not just the constraints of a biologically determined by critical period. In developmental biology and developmental psychology, a critical period is a phase during which organisms have high sensitivity to external stimuli deemed compulsory for the development of a specific skill. It may therefore be impossible, difficult or even less successful ultimately, if organisms fail to receive the proper stimulus, to have some particular functions develop in life during this critical period. Ideally, failure to learn a specific skill enables the cortical locations situated for such functions to remain into disuse; resultantly the unused areas of the brain will adapt to execute distinct function and hence will not exist again to carry out other functions anymore. The critical period concurrence for visual, vestibular, auditory systems indicates that the period of time may appear to be universal for all the other sensory systems emerging in organisms (Johnson and Newport, 1989, p 28). In order to confirm the availability of a particular critical period of a specific ability, one needs evidence that a point exists after which the behavior associated with the critical period declines to be related to age and that ability remains at a common level. This means that individuals exposed to a particular stimulus at a proper time should perform better than those exposed to the same stimuli after the critical period. This is the reason majority of studies that investigate language acquisition critical period are focused on the deaf children of the hearing parents in particular (Johnson and Newport, 1989, p 31). We can therefore state conclusively that the critical period hypothesis asserts that there exist a growth period in which a full native competence is probable for language acquisition. This period exists between early childhood and adolescence. The critical period hypothesis definitely has consequences and implications for learning programs and teachers though not accepted universally. Developmental biology and developmental psychology confirms that critical period in a life span is a period during which organisms have high sensitivity to external stimuli deemed compulsory for their development of a specific skill. In order to make certain the availability of a specific critical period for a specific ability, one needs evidence that there is a point beyond which the behavior that is associated with the critical period is stops to be related to age and that ability remains at the same level. Theories of language acquisition have asserted that adults do not acquire languages as fast as children due to both internal and external factors, and not due to lack of ability. For example, older learners seldom achieve a near native accent. Many authors have proposed that it is due to being beyond their critical period (Lennenberg, 1967, p 174). Background Information The critical period hypothesis was initially proposed by Wilder Penfield and Lamar Roberts in a paper Speech and Brain Mechanisms in 1959 (Lenneberg, 1967, p 175). Lenneberg asserts that constraints of maturation exist on the period of time in which acquisition of the first language takes place. He states that acquisition of first language is based on the neuroplasticity. If language acquisition does not occur within the period of puberty, then particular aspects of language may be learnt but its full mastery may never be achieved. This is the concept discussed in the hypothesis of the critical period hypothesis. An illustrative example is the case of thirteen year old Genie. She was held to a potty chair with diapers on her. She entirely had no language as her father had chosen to isolate her due to her retarded birth. Genie was not able to acquire any language. Critical period hypothesis detractors have cited that children rarely grow up in nurturing environment. They point out that the absence of language acquisition may be due to abusive environment in general and not just because of lack of language exposure (Lenneberg, 1967, p 178). It has been recently suggested (Lenneberg, 1967, p 188) that in “the absence of critical period, it may be due partially to the stagnant or retarded prefrontal cortex development among children”. Researchers have also indicated that retarded prefrontal cortex development and concomitant delay in cognitive control development may enhance conventional learning which allows children to learn with much ease language than cognitive mature adults. This prefrontal cortex developmental patter is unique to humans in learning language. Nevertheless, there exists an agreement in the acquisition of second language that there is a particular time period in which learning or acquiring second language can be easier than any period of time falling beyond or outside the period. Particularly, critical period hypothesis states that children from birth and puberty can easily acquire language than those in their post puberty stage. However, learners of second language after this critical period may indeed be able to acquire second language, but will show deficit performance, mostly due to lack of native like accent (Bialystok, 2002, p 200). The generalization of critical period hypothesis has its basis on the idea of neurology which suggests that function of brain is lateralized after puberty. In the illustration of Genie who was isolated up to the age of thirteen, she began to acquire language when re-introduced to a language; however she could not acquire fully the morphology and syntax of children who received the exposure from a younger age. The Genie case study hence implies that post pubescent learners are not likely to acquire morphology and full syntax of the second language as well as native like pronunciation (Johnson and Newport, 1989, p 210). Language acquisition The process of acquiring language includes steps through which people acquire perception and comprehensive language ability, as well as to use both words and sentences produced by others or themselves to communicate. Language acquisition often refers to the acquisition of the first language. This is unlike the acquisition of a second language which involves mastery of additional languages in both adults and children voluntarily and out of interest. The ability and capacity to use language successfully requires a person to acquire range of tools such as syntax, phonology, semantics, extensive vocabulary, and morphology (Bialystok, 2002, p 207). The ability to acquire and use language differentiates humans from the other beings. However, the major question on the language abilities is how they are acquired in the linguistic input by infants. In a linguistic context, input refers to all contexts, words and other forms of language in which learners are exposed to, which are relative to the proficiency acquired in first or second language. Natively, it is difficult to believe that infants have the capacity to acquire majority of language aspects without being taught explicitly, considering the complexity of the nature of languages of humans, and the limited cognitive abilities relative in infants. A child within their initial years of birth comprehends grammatical rules of the native language without necessarily being taught just as one may do so in school (Long, 2005, p 76). First language acquisition Acquiring first language is actually the native language acquired by infants at their early years in life, basically due to exposure to the language environment. The hypothesis of the critical period states that the initial life years entails the period of time in which language develops readily after which acquiring language is considerably difficult and may even be less successful ultimately. The hypothesis of the critical period on the first language acquisition is based on the evidence from victims of child abuse and feral children reared with no particular exposure to the human language and were not able to acquire and produce it. The hypothesis also illustrates the deaf children with inability to develop and demonstrate spoken language after their pubic age. There is also evidence that children with aphasia possess better chance of recovery than adults with the same condition. The critical period hypothesis asserts that children of age five to puberty falls in the period of time in which language readily develops and after which acquisition of language is difficult and may be ultimately impossible (Johnson and Newport, 1989, p 214). Acquisition of language is guaranteed during periods of childhood and is jeopardized progressively to the end of puberty. It even becomes improbable thereafter. As demonstrated by critical period hypothesis, physiological brain changes are conceivable causal factors of terminus of critical period for acquisition of language. Adults who have gone passed the critical period are most likely to experience enduring impairment of language resulting from brain damage compared to children. This is believed due to the resiliency of youthfulness of the neural reorganization. However, many people still assume that the basis of language acquisition lies in the tongue, lips or ear. This is ungrounded as even the mute and deaf people can possess language fully. This is also because people with no ability to use vocal words may have the ability to comprehend and use language. Therefore, first language acquisition depends on the form of language in which the child is exposed to in the early years of life. It is usually the native language (Birdsong, 2000, p 78). Second language acquisition Acquisition of the second language is learning or acquiring a second language after an establishment of a first language. It also refers to any language learned a part from the first language of a particular person. It refers to what the learners do and not practices in teaching language. This often happens when people speaking other languages other than English attend schools for the first time. A second language may be acquired or taught when the language is spoken at home, where the learner is internally motivated, when there is a better opportunity to learn the second language, and where the second language is needed. The capacity of an individual to use a second language depends on the ability of the family to talk in more than just one language. The academic discipline of acquisition of second language is relatively new and broadly based on applied linguistics (Bialystok, 2002, p 210). Acquisition of the second language can be integrated by heritage language learning; however, bilingualism is not incorporated often in second language acquisition. This is because bilingualism is seen as an end result of mere language learning, and not the process itself. Acquisition of second language should also not be contrasted with the acquisition of the foreign language; rather, similar fundamental processes in distinct situations are involved in the learning of foreign languages and learning of second languages. There are various theories of acquiring second language and how exactly a language is learned and none has been accepted by Second Language Acquisition researchers. This is because the theories often extend the critical period of acquisition of second language. Most definitely, aged second language learners seldom obtain native like accent and fluency that is displayed by the younger learners in spite of faster progress in the initial learning stages (Bley, 2000, p 100). Learning and acquiring a second language at a young age is better in the long term compared to learning at an older age. However, researchers have ascertained that some older learners too master second language even though they learned outside their presumed critical period. Although the window of acquiring or learning a second language does not completely close, some particular aspects of linguistics seem to be vastly affected by the learner’s age. For instance, older learners of a second language always retain an immediate foreign accent identified, including those who indicate a good language grammar. Most researchers have proposed a lower critical age for learning phonology than for learning syntax. However, majority of writers state that no particular critical period for learning any particular vocabulary in second language exists. There are factors other than just the age may even be particularly more pivotal in learning and mastery of second language successfully such as anxiety, personal motivation, input and output skills, time commitment and setting. Therefore, acquisition of second language is not subjected necessarily to the critical periods of biology, on average, however; there is a retarded ability to learn with the age (Bialystok, 2002, p 216). Stages of second language acquisition According to the hypothesis of the critical period, the acquisition of second language can be done in phases depending on the exposure or environmental factors of the learner as described in the above paragraphs. The following are the phases of second language acquisition: Stage 1 Pre-production: this is a salient period in which learners may have various words in their respective receptive vocabulary though not speaking yet. At this stage, learners may be able to repeat exactly what teachers say. They may also be able to copy word to word from the board and listen carefully. At this stage, the learners need a lot of repetition of the words of the second language and will probably benefit much from friends who speak that particular language. Stage 2 Early production: this stage often lasts for about six months in which learners develop active and receptive vocabularies. Learners begin to speak usually in one or two phrases. Stage 3 Speech emergence: this stage constitutes learners who have developed vocabulary and can communicate well with simple sentences and phrases. At this stage, learners beginning to ask simple questions though may not be correct grammatically. Stage 4 Intermediate fluency: at this stage, the learners have many active words and are beginning to produce and use more complex phrases and sentences through speech and in writing. The learners are also willing to express well their thoughts and opinions. Learners at this stage will often use the strategies derived from their native language in order to master content of the second language. Stage 5 Advanced fluency: this stage takes between four to ten years to be achieved proficiently. Learners at this stage are in near native ability to speak, write or perform in the content area of the second language. (Bley, 2000, p 80) People learning second language, as state earlier, is different from children acquiring their first language. Very few older learners of a second language will acquire the same competence as the native speakers of that same language. However, children learning a second language however are more likely to obtain native like accent and fluency than older learners. However, it is often very seldom than people who speak second language passes totally for a native speaker. This is because second language speakers make errors often from their first language. For instance, Spanish origins learning English as their second language may make a mistake by saying “Is sleeping” instead of “It is sleeping”, hence leaving the subject of the sentence out. This is a language transfer, the effect of the first language of the learners of the second language. The way learners speak their first language may also change when learning a second language in subtle ways. Traditionally, it is not easy to believe that children posses the capacity to acquire majority of language aspects without being taught explicitly, considering the complexity of the nature of languages of humans as well as the limited cognitive abilities relative in children. This can be with various language aspects such as syntax and pronunciation, as well as the things noticed and the gestures made (Mark, 1980, p 28). Children as quick language learners Small children, as has been described earlier, learn faster than older people. Adults seem to lose the capability of picking up new subjects like games, languages, computer programs, or music. Undoubtedly, it is true that children in most cases seem to learn quicker than adults. I very few years, they can master a new language and produce and use it competently. However, this fact is attributed partly to genetic and social pressure. As part of a developmental growth, the brain of the children possesses a natural capability of absorbing new information. Much of this results from social pressure. Children in school are forced to study many subjects, parents also pressurize them to learn music and practice new sports, and their playmates force them to do better in their games. Hence, their environment is a factor of learning motivation. These attribute to faster and quicker learning demonstrated by children compared to adults (Birdsong, 2000, p 80). Although many writers assert that adults are poor learners, I disagree. Adults majorly have various skills compensating for their decline in ability of their brain to remember or grasp any new information. Adults can also reorganize their learning through setting periods for practice or reading. They are able to build on their experiences and skills mastered already. Adults are however busy with family and work and therefore the society does not encourage them to learn as many adults feel that it is pointless to learn further as they have achieved already various goals in personal life and at work. Therefore in summary, we cannot generalize that children are better learners than adults. This depends on the motivation and the situation of a person, as well as the level of learning enthusiasm a person possesses (Johnson and Newport, 1989, p 217). Conclusion In summary, critical period hypothesis asserts that there exist a growth period in which a full native competence is probable on language acquisition. This period exists between early childhood and adolescence. The hypothesis of the critical period states that the initial years of human life is very crucial because it is the duration in which individuals acquire first language that is presented adequately. Generally, critical period is a limited duration of time in which events can occur, often to lead to transformation of some kind. It may therefore be impossible, difficult or even less successful ultimately, if organisms do not get exposed to the proper stimulus, to develop particular life functions during this critical period. The subject further states that if input of the language does not occur until this period of time elapses, the individual may never obtain full command of the language, most specifically the grammatical system (Long, 2005, p 38). In developmental biology and developmental psychology, a critical period in a life span is a phase during which organisms have high sensitivity to external stimuli deemed compulsory for their development of a specific skill. So as to confirm the availability of a particular critical period for a specific ability, one needs evidence that there is a point beyond which the behavior that is associated with the critical period is stops to be related to age and that ability remains at the same level. The critical period hypothesis definitely has consequences and implications for learning programs and teachers though not accepted universally. As stated in the background, “the critical period hypothesis was first introduced by Montreal neurologists, Wilder Penfield and Lamar Roberts in a paper Speech and Brain Mechanisms in 1959, which was published in 1967 by Eric Lenneberg together with Biological Foundations of Language”. Critical period hypothesis states that children from birth and puberty can easily acquire language than those in their post puberty stage. The generalization of critical period hypothesis is founded on the idea of neurological suggests that function of brain is lateralized after pubic stage. However, learners of second language after this critical period may indeed be able to acquire second language, but will show deficit performance, mostly due to lack of native like accent (Lennenberg, 1967, p 190). Many people have argued that children are quick learners, however, adults too can learn first depending on the circumstances prevailing. In language acquisition, adults can reorganize their learning through setting periods for practice or studying. They can build on their experiences and skills that they already mastered. In most cases, adults are preoccupied with family and work and therefore the society have limited motivation on them towards learning since majority of adults feel that there is no sense in learning further as they have achieved most of their goals in personal life and at work. We cannot therefore summarily generalize that children are better and quick learners than adults. The speed and ease of learning depends on the motivation and the circumstance of an individual and the degree of learning enthusiasm possessed by such individuals (Birdsong, 2000, p 91). References Birdsong, D. (2000). Whys and why nots of the Critical Period Hypothesis for Second Language Acquisition, London: McGraw Hill Bley, Vroman, (2000). How language is acquired in L1 and L2, New York: Springer. Bialystok, Ellen (2002) First Language Acquisition; on the reliability of robustness, a reply to DeKeyser, Cambridge: Cambridge University Press. Jacqueline S. Johnson and Elissa L. Newport (1989) Cognitive Psychology; Critical Period Effects in Second Language Learning: The influence of Maturational state on the acquisition of English as a Second Language. New York: SAGE Lennenberg (1967). Biological Foundations of Language, London: Springer Long, M. (2005). Problems with supposed counter-evidence to the Critical Period Hypothesis, London: Prentice Hall Mark S. Patkowski, (1980). The sensitive period for the acquisition of syntax in a second language, vol 30 (2), pages 449-469. Robert M.DeKeyser, (2000). Studies in Second Language Acquisition, Cambridge: Cambridge University Press Read More