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Biology 202, Spring 2005
First Web Papers
Almost seven years have passes since I came to the U.S. Although I came to the U.S without knowing much English especially how to speak it, I became an advanced ESL speaker over years. I communicate with people in English, I write papers in English, I read textbooks in English and I even dream in English. When I go home and speak Japanese, my native language, I drop many English vocabularies in the sentences. This shows that I feel very comfortable with English. However, it is still far away from being perfect and my struggles continue in many situations. I have begun to think that it is nearly impossible to write, speak or understand like a native speaker. "Will my English ever get closer to the native level?" This has been a question I have been wondering for a long time. Though I feel comfortable using English everyday, I sometimes feel weird and unnatural about speaking English. I can speak Japanese without thinking whereas I still need to remind myself of grammatical rules with English. There must be a language property within the brain, but I wonder if I use same parts of brain when I use Japanese or English. If I do, how do I differentiate to use two languages? If I do not, where does my English come from? Are there any differences between bilinguals who learn multiple languages in the early age and who learn later? Does the second language acquisition of age matter? I need to know how our language process takes place within the brain as well as its relationship to the brain. Also, it is important to mention the concept of critical age. Through my research, I found that there have many various theories of where the second language takes place within the brain as well as lab researches utilizing the recent technology. The research tends to result more heavily on the possibly of using a different part of brain between the first and the second languages these days, but there has not been a single answer found yet.
Within the brain, there are two areas called Broca's area and Wernicke's area. About 97% of people equip Broca's area and Wernicke's area only in the left hemisphere of the brain, and they are the areas that we think our language process takes place (1). Broca's area has properties of verbal production of language including speech patter, grammar and syntax, whereas the Wernicke's area has a property of understanding of what the words mean. According to the experiments with many children and the way they acquire the native language, Asher concludes that "comprehension comes before speaking" (2). Considering the functions of Wernicke's area and Broca's area, this conclusion shows that Wernicke's area has to "light up for along period of time before the circuitry of the left brain in Broca's area flickers on" (2). Also, in order to speak either after reading or hearing, the information is transmitted in a order of Wernicke's area, Broca's area and then Primary Motor Cortex(1). Thus, our language system is located mostly in the left hemisphere of the brain and we usually process the language through Wernicke's area to Broca's area by sending information.
One thing that becomes important to consider is what we often hear, "critical period" for language acquisition. An example of Genie has been one of the most famous researches that prove the possible existence of critical period for language acquisition. Genie, who spent her childhood life in a closet without verbal communication until the age of 13, never developed the adequate level of language. There have been many researches and we have associated the inability of acquiring a language with the plasticity and lateralization of the brain. Many scientists came to conclude that after the ages between two to twelve, the brain "appears to lose its plasticity for learning language" (3). Because somebody missed the period when the brain is still flexible enough to adopt much information including the language system, the left hemisphere of the brain does not possess it. Counting in the existence of critical period as well as the plasticity of the brain, it is not very practical to believe that people can successfully acquire the second language and reach the native speaker level, because the native language has been in the left hemisphere of the brain for a long time. Learning a language means "habituating the body and nervous system to new patterns" (4). If plasticity really does diminish after the critical period, how hard it is for the new language that is learned after the critical period to come into the left hemisphere of the brain where the native language system resides.
Many researches have looked at the brain differences between monolingual speakers and bilingual speakers. Recently, the research has also been paying more attention to the differences between bilinguals who learn the second language at the early age of their lives and bilinguals who learned at the later age. This also helps to explain the importance of the critical period and plasticity of the brain.
One of the hypotheses is that bilinguals who learn their second language at a later age process the second language through the right hemisphere of the brain whereas "early bilinguals" process the left hemisphere (3). The role of the right hemisphere of the brain has been paid attention. However, more researches have been done, and it seems that the right brain have a significant role in second language acquisition only in the early stage, but not in the later stage (5). It means that initial process of acquiring the language is done within the right hemisphere of the brain whereas leaning involves with the left hemisphere of the brain. However, these researches have not looked further yet and they have not asked where the second language is being processed within the left hemisphere of the brain, either a same area where the first language system exists or a different area.
The recent researches often utilize the high technology. The 1997 research done by Kim, Relkin, Lee and Hirsch has shown one of the most interesting findings through MRI. In their research, they conducted a study with six early bilinguals and six later bilinguals, who are all fluent with the second language. They look at the activity of the brain while they ask the speakers to talk to themselves in one of their languages while looking at various pictures. What they found out from this research was that the early bilingual's activity of both languages were located in the same region of Broca's area whereas the activity of the later bilingual was located in a separated region of Broca's area though it was adjacent to where the first language is processed (6),(7). They also found that the activity showed only in one region with Wernicke's area with both in their first language and the second (6), (7). According to these two hypothesis, we can presuppose that the second language acquired in the later age is processed in a different place from their first language is processed. Maybe the initial acquisition part involves with the right hemisphere of the brain, but when people learn and get used to the language, the second language starts to be processed in the close region to where the first language is processes, usually in the left hemisphere of the brain.
If it is the case that the first language and the second language which is acquired after a particular age are processed in the different parts of the brain, how much room is there for the improvement of the second language? It is probably not easy to say that there is a big space for an improvement to reach the same level as the first language, because the second language cannot fit into where our first language is, thus we cannot provide the best environment for the language acquisition. However, if the MRI research is right and the difference in activity between the two languages is not found in Wernicke's area, we can still assume that it is possible to learn the semantics property of the second language. Also, the activity difference in Broca's area means that the grammar and syntax properties may not be something that we have a control over.
There have been more researches going on in this field, and this finding might not the final result. Also, the improvement of the second language learned after puberty has some variations among people depending on the similarity of sounds and the syntax system between the first language and the second language. At this moment, I am content to suppose that my English processor resides in a different place from Japanese. If the research is right, my English never shares the residence with Japanese since I started learning English at a later age. After this research, something new puzzles me. If the bilinguals can process two types of language in the same area, I wonder if they ever get confused. Is it possible for human to acquire two or more languages perfectly and maintain both languages at the same level? I would like to know more about the language system and the brain.
1)Thinkquest website,The Brain and Communication
2)TPR website ,Organizing Your Classroom for Successful Second Language Acquisition
3) Dr. Loretta Kasper's ESL 91 on the web, Language Acquisition in Humans
4) Bryn Mawr Library Search , practical linguistics/ A sensible theory of Language by
Childs, Marshall R. The Yomiuri Shimbun, 4/11/2003
5)Stephan D Krashen's webpage , Second Language Acquisition and Second Language Learning
6) The University of Missouri-Columbia website , Bilingualism Comes in Different Ways
7)University of Washington website , Second Language Learning.
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