2 INTRODUCTION AND AIM OF THE THESIS
2.1 CENTRAL QUESTIONS AND ASSUMPTIONS
2.2 OUTLINE OF THE THESIS
2.3 DEFINING BILINGUALISM
3 LITERATURE REVIEW
3.1 AIM OF THE LITERATURE REVIEW
3.1.1 BIOLOGICAL AND PSYCHOLOGICAL CONSIDERATIONS IN SLA
3.1.2 MATURATIONAL CONSTRAINTS
3.1.3 EMPIRICAL STUDIES
220.127.116.11 Natural and Experimental Acquisition Rate Studies
18.104.22.168 Age of Acquisition and Ultimate Outcomes in SLA
22.214.171.124.1 Long-Term AO Effects
126.96.36.199 Nativelike Levels of L2 Proficiency
188.8.131.52 Theories about the Nature of the Critical Period
184.108.40.206 Biological Aspects
220.127.116.11 Socio-Psychological Aspects
3.2 RESUME OF THE LITERATURE REVIEW
3.3 REASSESSING LANGUAGE PROFICIENCY IN SECOND LANGUAGE ACQUISITION - A DYNAMIC APPROACH
4 GENERAL DESCRIPTION OF THE RESEARCH PROGRAMME
4.2 RESEARCH METHODS
18.104.22.168 The Background Questionnaire
22.214.171.124 Peabody Picture Vocabulary Test-III
126.96.36.199 Expressive Vocabulary Test
188.8.131.52 ScriptLog – A Tool for Analyzing Online Writing
184.108.40.206.1 The Frog Story
4.2.4 INSTRUMENTS OF ANALYSES
220.127.116.11 TALC – Total Analysis of Language and Culture
5 GENERAL DESCRIPTION OF THE EXAMINEES
5.2 ANALYSIS AND DISCUSSION OF GENERAL DATA
5.2.1 AGE AND SEX
5.2.2 EDUCATION AND OCCUPATIONAL STATUS
5.2.3 COUNTRY OF ORIGIN AND RESIDENCE
5.2.4 VARIETY OF LANGUAGES
5.2.5 LANGUAGE GROUPS AND AGE OF ACQUISITION
5.2.6 WAY OF ACQUISITION L1 / L2
6 ANALYSIS AND DISCUSSION OF VERBAL SCREENING TESTS
6.1 INTRODUCTION AND AIM
6.2 VERBAL SCREENING TESTS
6.2.1 THE PEABODY PICTURE VOCABULARY TEST III
18.104.22.168 Variation Analysis
22.214.171.124 Correlation Analysis
126.96.36.199 Comparative Analysis of L1 and L2
6.2.2 THE EXPRESSIVE VOCABULARY TEST
188.8.131.52 Variation Analysis
184.108.40.206 Correlation Analysis
220.127.116.11 Comparative Analysis of L1 and L2
6.2.3 PPVT-III AND EVT IN COMPARISON
18.104.22.168 Variation Analysis
22.214.171.124 Correlation Analysis
6.3 CASE STUDIES
6.3.1 GENERAL REMARKS
6.3.2 PPVT-III – EXAMINEES
126.96.36.199 PPVT-III - Examinee no. 2
188.8.131.52 PPVT-III - Examinee no. 6
184.108.40.206 PPVT-III - Examinee no. 9
220.127.116.11 PPVT-III - Examinee no. 21
18.104.22.168 PPVT-III - Examinee no. 22
6.3.3 EVT- EXAMINEES
22.214.171.124 EVT - Examinee no.7
126.96.36.199 EVT - Examinee no.14
188.8.131.52 EVT - Examinee no. 15
184.108.40.206 EVT - Examinee no. 19
220.127.116.11 EVT - Examinee no. 21
6.4 RESUME OF THE VERBAL SCREENING TESTS
6.4.1 PPVT III - TEST
6.4.2 EVT - TEST
7 FROG STORY
7.1 INTRODUCTION AND AIM
7.2 ANALYSIS OF THE WRITTEN FROG STORY NARRATIVES
7.2.1 PRODUCTION PROFILES
18.104.22.168 Variation analysis
22.214.171.124 Comparative Analysis of L1 and L2
7.2.2 LEXICAL DIVERSITY
126.96.36.199 Variation analysis
188.8.131.52 Correlation analysis
184.108.40.206 Comparative analysis of L1 and L2
7.2.3 THE CONSTRUCTION OF COMPLEX MOTION EVENTS IN 'THE JOURNEY OFF THE CLIFF'
220.127.116.11 Comparison of the mean number of segments in the 'journey off the cliff'
18.104.22.168 Variation analysis of the journey segments in L1 & L2
22.214.171.124 Examples – The 'journey off the cliff'
126.96.36.199 Analysis of the 'journey off the cliff' by means of ScriptLog
7.2.4 EVALUATIVE DEVICES IN THE FROG STORIES OF L1 & L2
7.2.5 COMPARATIVE ANALYSIS OF EVALUATIVE DEVICES IN L1 AND L2
188.8.131.52 Examples of evaluative devices in L1 and L2 frog story narratives
7.2.6 TOTAL TIME ANALYSIS IN WRITTEN FROG STORIES OF L1 AND L2
8 HYPOTHESES AND THEIR VERIFICATION BY TALC
8.1 INTRODUCTION AND AIM
8.2.1 HYPOTHESIS 1
8.2.2 HYPOTHESES 2
8.3 VERIFICATION OF THE HYPOTHESES BY TALC
8.3.1 DISCUSSION OF THE RESULTS OF HYPOTHESIS 1
184.108.40.206 With respect to the age of acquisition and years of L2 usage
8.3.2 DISCUSSION OF THE RESULTS OF HYPOTHESIS 2
220.127.116.11 With respect to the way of acquisition of L2 and multilingual competence
18.104.22.168 With respect to the personal motivation to use L2 with families and colleagues
22.214.171.124 With respect to cultural identity
126.96.36.199 With respect to linguistic self-confidence and self-evaluation (writing skills)
188.8.131.52 With respect to language and emotion
9 SUMMARY AND CONCLUSION
11.1 Q UESTIONNAIRE (M ULTILINGUAL L ANGUAGE T ESTING Q UESTIONNAIRE )
In the preface to this dissertation I would like to give some information to my background, my passion for biand multilingual research and the development of this thesis.
When I was only three weeks old, my parents took me to Liberia, West- Africa where I grew up within a multilingual and multicultural society. Liberia was Africa’s first republic and was founded in 1822 as a result of the efforts of the American Colonization Society to settle freed American slaves in West-Africa. Over the course of many years, slaves were relocated. In 1847 the colony became the Free and Independent Republic of Liberia. The country is the only black African state where English is spoken as a mother tongue. Liberian Standard English is the official language and the most prestigious variety of English spoken in the country. Because of Liberia’s history and political ties to the U.S., it is modelled on American English. It is used in formal political speeches, in the media and at all levels of the education system. However, the home language for the major part of Liberia’s population is a tongue that is called Liberian Pidgin English. Most of the well educated Liberians try to suppress this tongue because it is regarded as “bad English”. Integrated into the Liberian society I did not only become a speaker of Liberian Standard English but also fluent in the use of Liberian Pidgin. Through my family and school I acquired German, a Tyrolese dialect and French.
After a stay of sixteen years my family was forced to leave the country because of the outbreak of the civil war. At that stage I had already become a multilingual language user with several cultural identities. Today I know that my multilingual development was so successful because I identified positively with all the languages and cultures involved. As I have already mentioned in my master thesis (2003:40) a balanced bicultural bilinguality can only be achieved if the characteristics of cultural identity which are considered to be relevant for the acquisition of the two languages have a highly positive value for the bilingual’s identity without interference.
As a multilingual speaker, a second language teacher and a researcher in this field, I have always been fascinated by the topics of language and culture. In my master thesis (Wilscher 2003) I carried out an eight month field study collecting the data of fifty-two multilingual speakers from all over the world.
The results of this master thesis and moreover the passion for biand multilingual research were the kick-off for the following dissertation.
Mag.phil. Daniela Reichholf-Wilscher Leoben, Graz, Lausanne, Holderbank, May 2006
“If the human mind were simple enough for us to understand, we would be too simple-minded to understand it.”
2 INTRODUCTION AND AIM OF THE THESIS
My master thesis, which I completed in 2003, dealt with sociopsychological aspects of bilingualism. In this research I carried out an extensive field study investigating fifty-two multilinguals all over the world. The results of this thesis were based on detailed questionnaires and personal interviews. The first hypothesis predicting that bilingualism cannot only be achieved in childhood but also later, in adolescence or adulthood could clearly be confirmed. The results showed that a lot of late bilinguals, meaning those who acquired their languages consecutively have achieved rather high levels of proficiency in L2. The study also emphasized the importance of socio-psychological aspects and revealed that the relationship between bilinguality and cultural identity in the bilingual is very complex (Wilscher 2003:37). These findings aroused my interest to carry out a more detailed research in the field of adolescent and adult bilingualism.
In addition the ongoing debate in second language acquisition literature questions whether adolescent and adult learners of L2 are able to approximate native-like levels. Unfortunately, little empirical evidence is available to determine the ultimate levels of proficiency. Besides, empirical research on socio-psychological aspects such as the bilingual’s identity and its relation to language proficiency is still scarce and needs further investigation. In this thesis adolescent and adult bilinguals meaning subjects who acquired their languages consecutively are tested for the quality of L1 - L2 proximity from a cross-linguistic and cross-cultural approach.
At this point it has to be explained what the abbreviations L1 and L2 stand for. In this thesis L1 signifies the subjects' indicated 'first language'. This does not automatically imply that L1 is identical to the examinees' original mother tongue. As mentioned in my master thesis (Wilscher 2003:16) a bilingual simply needs one language more than the other or is exposed more to one specific language. Hence, as mentioned above, L1 is not always in line with the examinees' mother tongues and can also represent the subjects' dominant languages at the time of testing. L2 stands for 'second language' and was acquired later in life than L1.
2.1 Central questions and assumptions
The present thesis deals with the lives and languages of twenty-five adolescent and adult bilinguals. All of them have acquired their languages consecutively. Through an extensive research programme the subjects are tested from a cross-linguistic and cross-cultural approach for the quality of L1 - L2 proximity.
The main research question in the thesis is in what ways do L1 and L2 of adolescent and adult bilinguals differ regarding the results of verbal screening tests and selected aspects of written narrative competence? How and to what extent can the findings be associated to the results of the analysis of influencing socio-psychological factors?
It is assumed that biological constraints are not the single crucial factors for high levels of attainment but rather socio-psychological variables such as culture, identity, perception and attitudes.
The verbal screening tests, namely the PPVT-III (Peabody Picture Vocabulary Test - III) and EVT (Expressive Vocabulary Test), used to determine a person’s passive and active vocabulary knowledge of a language will show that the results of L1 and L2 will not differ significantly of each other in individuals showing positive affective variables in their bilingualism.
The level of language proficiency and the quality of L1 - L2 proximity is further investigated through a detailed analysis of written narratives composed in ScriptLog, a research programme for the online process of writing. This involves the analysis of five major linguistic variables: productivity, lexical diversity, the construction of complex motion events, and the use of evaluative devices. The last two variables give information on the amount of granularity and the condensation of information and can be classified between textual structure and the lexicon. Additionally, the time data of the written narratives recorded by ScriptLog will be evaluated and discussed.
The question is whether qualitative and quantitative differences between the five variables of investigation mentioned above are in line with sociopsychological variables, possibly influencing the development of late L2 learners.
Finally, are the scores of the verbal screening tests and the results of the written narratives in line with affective variables, such as age and way of acquisition, number of years of L2 usage, personal motivation to use L2, linguistic self-confidence, cultural identity and the emotional relation to a language?
2.2 Outline of the thesis
The following chapter provides a plan for the thesis.
In the first and theoretical part of this thesis the author would like to deal with some of the most important aspects concerning adolescent and adult bilingualism. The literature research and discussion will mainly focus on maturational and socio-psychological constraints. At the end of the chapter a resume of the literature research will sum up the most important theoretical aspects of the topic. Finally, my own opinion and theory concerning late adolescent and adult bilingualism will be presented.
The second part deals with the evaluation of the collected empirical data of a field study involving 25 adolescent and adult bilinguals. First, a general description of the research programme including a description of the tests and analyses tools will be given.
Further investigation deals with the precise analyses of the single tests, such as the Peabody Picture Vocabulary Test III, the Expressive Vocabulary Test (EVT) and the written narratives of a picture book story composed in ScriptLog, a computer programme, for analyzing the online process of writing. Finally, each test result will be discussed individually according to statistical analyses and case studies.
Then, several hypotheses will be put forward on the theoretical part of the thesis, and the author's own assumptions. These hypotheses will be tested by means of individual language test results in combination with the background information of the examinees gathered through a questionnaire. Finally, these hypotheses will be reflected and discussed.
2.3 Defining bilingualism
When people hear the term bilingual many imagine an individual who speaks two languages perfectly. For them someone who is truly bilingual is two native speakers in one. They imagine that such a person can speak, understand, read, and write in two languages at the highest levels.
The question of how to define bilingualism or multilingualism has engaged researchers for a very long time. Some researchers have favored a quite narrow definition of bilingualism and argued that only those individuals who are very close to two monolinguals in one should be considered bilingual. More recently, however, researchers who study bilingual and multilingual communities around the world have argued for a broad definition that views bilingualism as a common human condition that makes it possible for an individual to function, at some level, in more than one language. The key to this broad definition of bilingualism can simply be defined as 'more than one'.
This would imply that a bilingual is not necessarily an ambilingual, namely an individual with native competence in two languages. Some bilinguals possess very high levels of proficiency in both languages in the written and the oral modes. Others display varying proficiencies in comprehension and or speaking skills depending on the area of experience in which they use their two languages.
According to this perspective, a bilingual may be a person who is able to produce written or spoken utterances in more than one language. Thus, people who are able to read in a second language but unable to function in the spoken language are considered to be bilinguals as well. Such bilinguals are said to have receptive competence in a second language and to be more bilingual than monolinguals who have neither receptive nor productive abilities in a language other than their first. This argument compares total monolingualism versus a minor degree of ability to comprehend a second language.
Trying to define bilingualism one soon realizes that there exist many definitions. According to Webster’s Dictionary (1961), bilingual education is defined as having or using two languages especially as spoken with fluency characteristic of a native speaker; a person using two languages especially habitually and with control like that of a native speaker. and bilingualism is defined as the “constant oral use of two languages.” The New Edition of the Oxford Advanced Learner’s Dictionary (1995) defines bilingual as being “able to speak two languages equally well” and as “having or using two languages”. Leonard Bloomfield (1933:55f) writes that In the extreme cases of foreign language learning, the speaker becomes so proficient as to be indistinguishable from the native speakers round him... In the cases where this perfect foreign language learning is not accompanied by loss of the native language, it results in bilingualism, [the] native-like control of two languages.
In addition, bilingualism can be defined as “having a choice of two available languages for conversation” (Harris: 1992:299).
At this point the following question arises: What are the criteria for describing a person as bilingual? Does a bilingual have to be monolingual-like in both languages? Or how much of the weaker language does a bilingual need to know to be called bilingual? Another interesting question would be whether adults raised with only one language can later become bilingual as well.
Considering the different forms of bilinguality and bilingualism (Wilscher 2003:18) this thesis exclusively deals with consecutive or late bilingualism respectively. In contrast to simultaneous bilinguals consecutive bilinguals began to acquire a second language after infancy, meaning after the basic linguistic acquisition of their mother tongue has been achieved (Wilscher 2003:15).
Considering a great number of definitions one will soon realize that they range from native-like competence in two languages to a minimal proficiency in a second language. Concerning my own opinion the definition of “having a native-speaker-like control of two languages” is a rather strong concept and it does not meet reality very often. Personally, I would consider it to be the highest possible level of bilingualism and it should be seen as an ideal. Besides, few people are truly balanced bilinguals, meaning individuals who possess about the same fluency in two languages. Bilinguals usually have one dominant language. This dominance in one language may be different for listening and speaking or for reading and writing and usually changes over time.
Finally, I tend to favour the view that a definition of bilingualism should not ask for perfection, but for basic knowledge and basic understanding. The term ‘multi-competence’ which was introduced by Cook (1991) to mean ‘knowledge of two or more languages in one mind’ perfectly describes my concept of bilingualism. This means that it should be considered more important to make oneself understood in a foreign language than to speak two or more languages fluently and equally well. Therefore, the quite con troversial word bilingual could be replaced by a more neutral expression, namely to live with two or more languages.
Throughout this thesis the tested subjects will generally not be measured against native speakers of the respective language, meaning monolinguals who speak the language they learnt in childhood. The main argument for this decision is that bilinguals should be measured by their success at being L2 users and not by their failure to speak like native speakers. Hence it follows that realized comparisons of adolescent and adult learners of L2 with native speakers of the respective language will definitely not be treated as a matter of proficiency.
3 Literature Review
3.1 Aim of the literature review
At the beginning of this literature review it has to be mentioned that a great deal of important aspects concerning bilingual research were discussed in detail in the theoretical part of my master thesis “A multilingual Database: Socio-psychological aspects of bilingualism” in 2003. In this master thesis psycholinguistic and neurological aspects as well as sociopsychological aspects of bilinguality were introduced and discussed extensively. To avoid unnecessary repetitions the theoretical part of this present thesis will concentrate on the most important theoretical aspects and questions in the field of adolescent and adult second language acquisition relevant for the research questions in the empirical part. The literature review will first give an overview of the ongoing debate of biological and psychological constraints in second language acquisition research. Another topic will deal with individual differences in late bilinguals. Finally some methods of measuring language proficiency will be discussed.
3.1.1 Biological and Psychological Considerations in SLA
Basic aspects of language development and the age question were discussed in my master thesis (Wilscher 2003:29-32). In the conclusion of this chapter I wrote that I personally think that it is very difficult to generalize the age-question and define a boundary for learning languages effortlessly (Wilscher 2003:31). Furthermore I agreed that children who learn more than one language before adolescence will acquire those languages with more ease and native-like ability than they would trying to study those languages as adults (Wilscher 2003: 32).
However, from my personal experience and the interviews carried out for the research in my master thesis I know that a lot of late bilinguals, meaning those who acquired their languages during adolescence and adulthood, achieved extraordinary ultimate levels of proficiency in L2 comparable to those of native speakers. Such successful cases are mostly consid ered to be exceptional and are the admiration of all. By way of contrast, for early bilinguals ultimate levels of proficiency short of native like control are seen as a definite and inexplicable failure.
Such striking differences without plausible explanations lead us to the conclusion that a lot of questions that have been investigated over the years still remain unanswered.
The focus of this chapter is on providing a review of the research which has been carried out on maturational constraints in second language acquisition (SLA) so far. I will begin by introducing the Critical Period Hypothesis (Lenneberg, 1969) with its original formulation and resulting theories in the field of research. In the section that then follows the question whether a boundary marking the end of learning languages effortlessly really exists will be discussed. Moreover it should be questioned whether it is possible to attain full native like proficiency in a second language, and if there is an age of onset (AO) limit for such an attainment. Finally it will be discussed whether it is possible to reach nativelike proficiency starting at any age.
Some research into psychological and neurological aspects of language emphasized the idea of a so called ‘critical period’ during which children are particularly adept at acquiring language. One of the first publications in this field came from the neuroscientists Penfield and Roberts in 1959. They stated in Speech and Brain Mechanisms that children are more successful second language learners than adults and that they have biological and neurological advantages. Moreover they contend that “the child’ s brain has a specialized capacity for learning language” (Penfield & Roberts 1959:240) and that “[t]here is a biological clock of the brain” (Penfield & Roberts 1959:237). Concerning cerebral flexibility and “direct learning” from the input both researchers suggest that until the age of nine a child can learn “two or three languages as easily as one.” From their point of view poorer levels of attainment clearly result from later ages of onset (AOs). Moreover they emphasize that children become “more analytical” and learn “indirectly” via their first language after the age of nine. In 1967 Lenneberg, a psycho-biologist, who was inspired by the findings and insights from the work of his contemporaries (e.g., Penfield & Roberts, 1959), wrote in Biological Foundations of Language that there was “a biologically based critical period” for learning a second language. Lenneberg explained the loss of the biological predisposition for language acquisition by the completion of hemispheric lateralization. He argued that this completion of hemispheric lateralization coincided with puberty. Hence he concluded that there must exist a time span for the acquisition of a second language between age 2 and puberty, the so-called critical period.
Lenneberg’s original formulation of the Critical Period Hypothesis (CPH). Lenneberg contended that: automatic acquisition from mere exposure to a given language seems to disappear [after puberty], and foreign languages have to be taught and learned through a conscious and labored effort. Foreign accents cannot be overcome easily after puberty. However, a person can learn to communicate at the age of forty. This does not trouble our basic hypothesis. (1967, p. 176)
Taking a closer look at the original formulation of Lenneberg’s CPH and the ongoing research on maturational constraints it can be said that scientists in this field have developed research questions based either on factors that were mentioned by Lenneberg in this original formulation, or on factors that could be derived from his hypothesis. At this point three theories on which scientists have based their research so far can be advanced.
The first theory focuses on the attainability of nativelike ultimate proficiency from mere exposure to a certain language and clearly coincides with Lenneberg’s original formulation of the CPH. Regarding this theory, the CPH would be clearly falsified if nativelike proficiency were found in second language learners who acquired a language naturalistically and outside a certain time span.
The second theory is concerned with the relationship between age and ultimate attainment. It is usually the case that younger learners outperform adolescent or adult learners in the long run. In case of equal learning conditions, this theory is falsified if adult learners reach higher levels of ultimate attainment than younger learners.
The third theory deals with the well-believed fact that younger learners are better language learners than older ones. This theory is falsified if older learners are better at language learning than the younger learners. Unfortunately this hypothesis disregards the level of ultimate attainment and the condition of nativelike proficiency (e.g., Snow and Hoefnagel-Höhle, 1978).
As we can see researchers in this field have been debating the existence of a critical period for language acquisition since the late 1960s. The three theories mentioned above demonstrate very well that most of the debate and confusion has largely been created due to the fact that different researchers have based their research questions on different interpretations of the CPH.
Today, most of the researchers would probably agree that younger learners generally have long-term advantages in the acquisition of a second language and usually outperform adult learners in the long run. Besides, scientists who carried out the relevant studies in this field have found no counter-evidence to this assertion (Krashen, Long, and Scarcella, 1979; Long, 1990; Singleton, 1989, 2001).
However, the most current research in the field questions whether different levels of ultimate attainment in second language learners should be explained by biological constraints, or by socialpsychological factors (Birdsong, 1999a; Hyltenstam and Abrahamsson, 2001; Marinova-Todd, Marshall, and Snow, 2000; Scovel, 2000; Singleton, 2001; Wilscher, 2003).
In this introduction I attempted to give an explanation of how the ongoing, and quite complex controversy about the existence of a critical period for language acquisition came into existence.
3.1.2 Maturational Constraints
What makes us think that there might be a critical period for language acquisition in general? At this point some facts from delayed first language acquisition and language deprivation should be mentioned. Some wellknown cases of delayed language exposure, with AOs delayed beyond six or seven, due to deprivation or isolation resulted in a less than complete ultimate attainment. Gleitman and Newport (1995, pp. 10ff) for example described the cases of Genie (Curtiss, 1977, 1988), Chelsea (Curtiss, 1988, 1989) and Isabelle (Davis, 1947). In a comparison of this three delayed first language acquisition cases they illustrate the effects of being deprived of linguistic input. Genie who was isolated and deprived of linguistic input from the time she was one and a half years old until she was discovered at the age of thirteen learned some language but stopped short of native-like attainment in morphology and syntax.
Another case of severely delayed language access is Chelsea, misdiagnosed as retarded in childhood, when in fact she was cognitively deaf, only discovered when Chelsea was thirty-one years old. Chelsea’s utterances had almost no discernable structure at all. Her speech was less language-like than Genie’s. In contrast, Isabelle who was imprisoned with her mute, uneducated mother, started at age seven and caught-up to normal age levels. The cases of Genie and Isabelle in comparison to Chelsea lead us to the conclusion that the potential to acquire nativelike proficiency in a first language clearly decreases between age seven and puberty. However, some researchers in this field strongly doubt that full nativelike proficiency in a first language is attainable given AOs up to the age of six or seven. Other data showing effects of deprivation during very early phases call this contention into question. The case of Isabelle is the only evidence, which supports the age limit of six or seven. But even this case cannot be described as truly scientific evidence as there is no reliable linguistic analysis available.
Many researchers agree that if there exists a certain window of opportunity for language acquisition during an early period of life, but less so later in life, there should be a similar window of opportunity in second language acquisition showing parallels to the first language contexts.
During first language acquisition certain cortical areas become committed and begin to accept input data that lead toward a fine-tuning of the activation weights governing processing (MacWhinney 1997:136). Hence, beginning to learn a second language there is already an existing neural structure involved in the processing of lexical information in the native language. It is assumed that an increasing automatization of the first language system is considered to be the main reason why adult learners face difficulty in learning a second language. The more automated the first language system becomes the less it is available for restructuring (Mac Whinney 1992:383).
However, several researchers in the field strongly take the view that nativelike proficiency can also be reached in a second language given early AOs (Hyltenstam, 1992; Johnson and Newport, 1989; Oyama, 1978; Patowski, 1990). Additionally, researchers who carried out studies with late second language learners on nativelike behavior; such as intuitive judgment tasks (Birdsong, 1992, White and Genesee, 1996) and pronunciation (Bongaerts, 1999; Bongaerts, Mennen, and van der Slik, 2000; Moyer, 1999) contend that nativelike attainment in certain sub-components of language can clearly be achieved.
Yet it has to be mentioned that not all of those who started to acquire a second language during an earlier phase of life reach nativelike proficiency. This phenomenon was already discussed and confirmed in my master thesis and further underlined by various scientific studies (Bialy stok and Miller, 1999; Butler, 2000; De Keyser, 2000; Flege, 1999; Hylten stam, 1992; McDonald, 2000; Harley and Wang, 1997; Wilscher, 2003).
These studies show, among others, that language, be it L1 or L2 develops gradually, sometimes by leaps and bounds, often appearing to stagnate or even regress (Pulvermüller and Schumann, 1994). What should be made clear here is that the bilingual’s languages may have an effect on each other at any age. At all times and stages of life, acquisition is largely dependent on the nature of input, social, psychological and environmental factors. Unfavorable changes in these domains may lead to negative effects on the bilingual’s ultimate language proficiency and he or she may develop full competence in only one language. By the way, it should be mentioned that few people, be it early or highly successful late bilinguals, are truly balanced bilinguals, meaning that they possess about the same fluency in two languages. On a related note, Harley and Wang (1997) conclude, “monolingual-like attainment in each of a bilingual’s two languages is probably a myth (at any age)” (p. 44). In this context reliable data of long-term effects of weak second language acquisition would be interesting to discuss as well. Unfortunately these cases remain unclear as they have not been studied yet.
3.1.3 Empirical Studies
The following section will provide an insight into the available empirical data. Acquisition rate studies will be discussed.
184.108.40.206 Natural and Experimental Acquisition Rate Studies
Some researchers have focused their research on naturalistic and experimental acquisition rate studies. Concerning naturalistic rate studies the examinees have been exposed to the target language in an L2 environment. In the case of experimental laboratory studies the subjects have first been taught a number of aspects of a language unknown to them. Afterwards they were tested for their L2 proficiency. While a number of re searchers contend that older learners are more successful in the acquisition of a second language than younger learners (e.g., Asher and Price, 1967; Loewenthal and Bull, 1984; Snow and Hoefnagel-Höhle, 1977, 1978), others are convinced that younger learners have advantages over older learners (e.g., Tahta, Wood, and Loewenthal, 1981a, 1981b; Yamada, Takatsuka, Kotake, and Kurusu,k 1980).
In contrast to these results other scientists have found no significant rate differences between younger and older L2 learners at all (e.g., Slavoff and Johnson, 1995). In the meantime, several researchers pointed out that the reported experimental studies clearly favor older learners because the tests are quite demanding in cognitive skills and test-wiseness (e.g., Long, 1990, Loewenthal and Bull, 1984). Thus, the applicability of these studies has been called into question as the learning rate of L2 is definitely not able to define the existence or non-existence of a critical period. Additionally, “the issue of initial learning rates is a separate one, and one which does not bear directly upon the validity for the CPH.” (Patkowski, 1990, p. 75).
Through these findings rate of acquisition studies fell out of fashion in the 1980s and the preponderance of research then focused on long-term AO effects.
220.127.116.11 Age of Acquisition and Ultimate Outcomes in SLA
18.104.22.168.1 Long-Term AO Effects
The ongoing debate on the existence or non-existence of maturational constraints in second language acquisition then lead researchers to investigate long-term AO effects. Several studies, which were carried out, showed a clear correlation between AO and ultimate attainment in L2 (Asher and García, 1969; Oyama, 1978; Patkowski, 1980). Interestingly, these studies showed, among others, that length of residence (LOR) and degree of motivation have a limited scope of importance in L2 ultimate attainment outcomes. This led to the conclusion, that young children are bet ter L2 learners than older ones. Age of onset of learning a second language is an important factor in reaching high levels of ultimate attainment in L2. In the frequently cited study of Johnson & Newport (1989), it was found that Korean and Chinese speakers who had arrived in the USA between the ages of three and seven were judged as native-like on production of grammatical structures in English. In contrast, those who arrived between ages eight to ten did not achieve native-like levels in this domain. The Johnson & Newport study (1989), though widely appreciated as providing unambiguous evidence of a critical period for L2 morphosyntactic development (e.g., Birdsong, 1999; DeKeyser, 2000; Long, 1990), is not without its critics (e.g., Bialystok & Hakuta, 1994; Bialystok & Miller, 1999; Eubank & Gregg, 1999). Researchers doubt the method, the materials used in the study and the way the data were interpreted.
Following the study of Johnson & Newport, DeKeyser (2000) carried out a modified grammaticality judgement test investigating the second language proficiency of fifty-seven Hungarian learners of English with ten years of residence or more in the USA and with AOs between one and forty years. The study revealed no significant correlations between the test scores and variables such as LOR, years of schooling, or age at time of the test. However, DeKeyser reported a negative correlation between AO and the achieved scores in the grammaticality judgment tests. Additionally, it was observed that late L2 learners who performed within the range of early starters showed a high aptitude for language learning. Although De- Keyser´s study can be seen as an improvement in the field the problem is that many researchers doubt the accuracy of the aptitude scores. In fact, one of the most successful late L2 learners in the study showed a lower score in the verbal aptitude test. And finally, no native English controls were included in the study to evaluate nativelike proficiency.
Many researchers, such as White and Genessee (1996), claim that studies that have arbitrarily selected learners with different AOs clearly reveal that children achieve higher levels of ultimate attainment than adults.
Nonetheless all these studies “leave unanswered the question of whether late L2 learners can ever attain linguistic competence that is indistinguishable from monolingual native speakers” (p. 235).
In conclusion, neither rate of acquisition studies nor investigations of longterm AO effects could provide an answer to the existence or nonexistence of maturational constraints in second language acquisition.
22.214.171.124 Nativelike Levels of L2 Proficiency
The debate on the problem has been continued and L2 research to date has been trying to demonstrate that late L2 learners, given certain advantageous circumstances in the process of acquisition, are able to achieve native like levels of L2 proficiency. Viewed in this light, such successful late L2 learners would be the proof that factors other than maturation are responsible for late starters’ typical failure in achieving nativelike proficiency (Patkowski, 1990). Thus, this section should give an overview of research studies carried on ultimate attainment that have called the CPH into question by providing test results of late second language learners who have reached native-like language proficiency.
One of the first studies was that of Coppieters (1987) comparing native speakers of French with near native speakers. In this study Coppieters distributed a syntactic / semantic judgment task to twenty-one highly successful L2 language learners. On a first glimpse, the tested subjects were judged as nativelike. Interestingly, a closer analysis revealed that the near native speakers did not only differ in accent but also developed a grammar different from that of the native speakers. In the same vein Birdsong (1992) found that fifteen of twenty late L2 language learners of French achieved native speaker levels of proficiency on a grammaticality judgment task.
Researchers also carried out several studies in the area of phonology (Bongaerts, 1999; Bongaerts, Planken, and Schils, 1995; Bongaerts, van Summeren, Planken, and Schils, 1997). Numerous studies in this field clearly revealed nativelike levels of ultimate attainment in the pronunciation of highly proficient L2 language learners. Another study in the area of phonology was carried out by Moyer (1999). This study investigated very advanced and highly proficient American learners of German as a second language. The judges involved in this study were able to identify the L2 subjects from the native ones. Moyer’s study pinpoints, among other things, that the subjects reached more native accent ratings for more isolated task items such as word lists, reading aloud of sentences etc. In contrast, free production clearly resulted in foreign accent ratings. Additionally, Moyer (1999) states that “the inclusion of tasks beyond word recitation naturally involves suprasegmental features as well as lexical, syntactic, and pragmatic fluency” (p. 86). Hence, the problem with studies in pronunciation is that “a clean measure of phonological fluency alone is not possible for extended, naturalistic speech,” since raters are “indeed influenced by structures beyond L2 phonological production in their assessments of performance” (ibid.).
Another group of researchers (Ioup, Boustagui, El Tigi, and Moselle, 1994, Ioup, 1995) published a case study about Julie, a highly proficient and very talented second language speaker of Egyptian Arabic. Julie, whose native language was English came to Egypt at the age of twenty-one and had received no formal instruction in Egyptian Arabic. Concerning her personal life, Julie was married to an Egyptian and was the mother of two children. Her LOR at the time of the case study was twenty-six years. Another extraordinary talented L2 speaker was Laura, whose L2 was American English. Laura, who was also married to an Egyptian, spoke several varieties of Arabic. Here it has to be mentioned that Laura got formal L2 instruction. Her LOR at the time of the case study was ten years.
Although the Ioup et al. study can only provide an insight into two single case studies it is worth mentioning because of the employment of a large set of elicitation instruments. Both Julie and Laura had to carry out quite demanding tasks and were assessed for production, dialect differentiation abilities and grammatical competence. On the whole, the results showed that both, Julie and Laura had achieved native like levels of language proficiency in L2. Yet, single judgments showed some minimal deficits in pronunciation. Through their case studies Ioup et al. (1994) revealed that there are exceptional late L2 learners who are able to perform within the range of native speakers. The researchers conclude that in such cases the neurocognitive change does not happen in the usual way, although it remains uncertain whether the ordinary acquisition system continues to function or whether an alternative learning system takes over.
Another research project by White and Genesee (1996) demonstrated that native-like competence in an L2 is achievable, even by older L2 learners. After a careful screening White and Genesee divided their subjects into two groups. The L2 near-native learners of first group had started to acquire English as a second language before the age of twelve. The other group comprised the non-native speakers who had started after the age of twelve. The subjects then had to go through a grammaticality judgment test and a question formation test, which included sentences relevant to Subjacency and the Empty Category Principle. The results of this study showed enormous differences between the non-native group and the native group. In contrast, almost no differences were found between the near native and the native group. These authors use the existence of nativelike competence in an L2 as evidence to show that even older L2 learners have access to Universal Grammar (UG). Nonetheless, the authors additionally mention that "... indeed there is a negative correlation between age of acquisition and competence in an L2..." (White and Genesee 1996:234)
Further research in this area was carried out by Hyltenstam (1992) who investigated the grammatical and lexical performance of twenty-four nearnative seventeen to eighteen year old Spanish and Finnish L2 learners of Swedish. Sixteen of the twenty-four subjects had AOs at six years or earlier. Eight subjects had AOs at seven years or later. Both groups were highly frequent users of L1 as well as L2. Hyltenstam had worked out a quite demanding test battery including free speech through oral retellings and an untimed written composition. The final results revealed that the group of the late L2 starters clearly did not perform within the range of native speakers. However, the earlier L2 starters had clearly reached the levels of native speaker proficiency. Hyltenstam (1992:364) states that “[the] age of 6 or 7 does not seem to be an important period in distinguishing between near-native and nativelike ultimate attainment.” Yet, he adds that “an early AO may be a necessary although not sufficient requirement for nativelike ultimate attainment” (ibid.), referring to those early learners who did not perform within the range of native speakers.
In a recent study Hyltenstam and Abrahamsson (forthcoming) investigated twenty highly proficient L2 speakers of Swedish. The researchers created four groups according to the AOs of the examinees (4-5, 8-10, 12-15, and 19-23). All of the subjects had a LOR of ten years or more and were regular users of L1 and L2. These groups were compared to two groups matched for age and educational background. One of these groups comprised native speakers of Swedish, the other one advanced non-native speakers. The quite demanding test battery included a test of perception, a cloze test and a grammaticality judgment test. The results showed enormous differences between first language speakers and second language speakers of all AO groups. Interestingly, this study revealed that not even the very young L2 learners performed within the range of native speakers. The researchers report, among others, that the differences between the created AO groups were rather small.
Butler (2000) reports similar results revealed by a study with adult Chinese L2 speakers of English. The study showed that early arrivals achieved higher scores than mid arrivals, who again scored better than late arrivals. Further research results (Bialystok and Miller 1999; McDonald, 2000) are in line with the study carried out by Hyltenstam and Abrahamsson (forthcoming) and report to have found subjects with very low AOs, who did not reach nativelike ultimate attainment. A lot of the studies on late, advanced L2 learners were simply not able to provide reliable evidence of full proficiency in the L2 (Coppieters, 1987; Hyltenstam and Abrahamsson, forthcoming; Ioup et al., 1994; Moyer, 1999). The authors of these studies often conclude that the investigated subjects deviate very little from native norms. This implies that the examinees had definitely not attained native speakers norms.
What research to date has made crystal clear, however, is that there are exceptional late L2 learners who have the ability to reach high levels of ultimate attainment, perhaps even nativelike proficiency in L2. Several researchers contend that these exceptional learners are usually highly motivated (Moyer, 1999), have an aptitude for language learning (De- Keyser, 2000; Harley and Hart, 1997; Ioup et al., 1994), or have received formal L2 instruction.
The crucial and open question is what the reasons are for the previously demonstrated and discussed differences in ultimate attainment in late L2 learners? Are these reasons indicators of fundamental differences in the acquisition process or are there intervening variables that cause these differences?
126.96.36.199 Theories about the Nature of the Critical Period
From the preceding discussion of research, it may be concluded that the CP is obviously modular in nature, when applied to second language acquisition. Hence, the following section should shortly review different formulations and interpretations of the CPH. Concerning the nature of the critical period Harley and Wang (1997) advanced six sequenced characteristics: a) an onset, b) a terminus, c) an intrinsic component, d) an extrinsic component, e) an affected system, and f) ultimate causes. The terminus issue has been the most debated characteristic in this area of research.
Regarding the onset of a critical period for language acquisition, there is no consensus of opinion. Lenneberg (1967) suggested an onset of the critical period at the age of two, co-occurring with increased syntactic development at that age. Yet, other researchers support the view that the onset of a critical period already starts at the age of six months, when babies have already begun to recognize and sort out the necessary sounds, or phonemes, of their own language and turn-taking has taken place (Singleton, 1998, p. 78). A lot of confusion in the discussion on the onset of a critical period has been caused by the fact that several authors have transferred the onset of first language acquisition to the onset of second language acquisition.
Singleton (1989) provided a discussion on the onset of multiple critical periods for certain linguistic domains (phonology, grammar, lexicon and discourse). Singleton’s discussion clearly refers to the Windows of Opportunity hypothesis which also Schachter (1996) and other linguists in the course of research have mainly considered the factor of timing and age of acquisition in second language acquisition (Genesee at al., 1979; Harley, 1986; McLaughlin, 1985a; Snow and Hoefnagel-Höhle, 1978; Swain, 1981). Others such as Schumann (1997) and Bialystok (1995) have attached less importance to the onset of a critical period for language acquisition and instead highlighted the factor of motivation and other psychological aspects of language learning.
As mentioned earlier the offset or rather terminus of the critical period has been a quite controversial issue so far. The first researchers to deal with this question (Penfield & Roberts, 1959) suggested that the critical period ends at the age of nine. They concluded, that due to a reduced cerebral flexibility a child at that age starts to learn a second language via the units of the first language. Lenneberg (1967) equated the offset of the critical period with puberty arguing that it coincides with the completion of lateralization.
The bulk of empirical research on the age of acquisition and ultimate levels of attainment lead researchers to define age limits for certain linguistic domains. In the case of phonology Long (1990, p. 280) suggested an upper limit at the age of six “in many individuals” and at the age of twelve for the rest. Regarding morphology and syntax Long (1990) contends that the age of fifteen seems to be the upper limit for nativelike attainment. Nonetheless, other researchers such as Johnson & Newport (1989) claim that the age of six or seven may be relevant for morphosyntax or rather morphosyntax and the lexicon (Hyltenstam, 1992).
Other characteristics of a critical period, which should be mentioned here, are the intrinsic and extrinsic component. The intrinsic component is a kind of genetically determined mechanism that sets the path for language acquisition. Yet, up to now there has been no clear answer to the question in what ways such an intrinsic component would constrain second language acquisition, except within the field of UG.
The extrinsic component covers the relation between the environmental factors and language development. In this context Harley and Wang (1997, p. 24) state that these factors have been underestimated so far. As mentioned earlier in this chapter, a low AO is no guarantee to attain nativelike proficiency in a second language. Other, intervening variables such as frequency, the quality of input, identity issues have a significant influence on ultimate attainment and probably interact with maturational constraints (Hyltenstam, 1992, p. 364).
Concerning complete nativelike ultimate attainment in L2, to date no reliable data has provided clear evidence for specific domains being maturationally constrained. However, a lot of researchers support the view that maturational constraints occur within UG. Schachter (1996) for example contends that the Subjacency and the Governing Category Principle are sensitive to maturational constraints.
Summing up, the results of the studies on maturational constraints in L2 acquisition absolutely do not confirm the existence of a global critical period for all linguistic domains but rather, if at all, multiple critical periods for certain linguistic domains. Most of the research studies carried out revealed that even very proficient late L2 learners performing within the range of native speakers showed minor differences to native speakers.
188.8.131.52 Biological Aspects
Reviewing the literature on the critical period hypothesis one soon realizes that most of the scientists have tried so far to explain that as we age the human brain's networks cement in place. In other words, the brain looses plasticity. In simplified terms, cerebral plasticity is “the ability of neurons to make new connections, and varied connections depending on the stimulus” (Eubank and Gregg, 1999, p. 69). Interestingly, Pulvermann and Schumann (1994, p. 691) state that the “strengthening of connections between neurons probably represents the neurobiological basis for learning”, including language acquisition.
The question, then, becomes: Which kind of strengthening might have an influence on an increasing connectivity of neurons? At this point the process of myelination should be mentioned. In addition to lateralization, myelination is another neurological process that has been identified as contributing to the multiple critical periods. The myelination of cortical areas is a process by which brain cells are covered with a fatty white substance called myelin, which aids in the transmission of information between larger cerebral distances, starting at the fetus stage and continuing for several decades. Pulvermüller and Schumann (1994:713) state that “around puberty, all cortical areas, except perhaps the higher-order association cortices, have reached their full level of myelination.” Furthermore the two scientists claim that language areas around the Sylvian fissure myelinate before the higher-order association cortices. Hence, they conclude that there must be a relationship between brain correlates and language acquisition potential. In supporting their position, Pulvermüller and Schumann refer to the socalled A-system and B-system labeled by Braitenberg, 1978. These are simply two systems of cortical connections between neurons. The A-system uses apical dendrites and axons that reach far from the cell body and connect different cortical areas. The other system uses basal dendrites, close to the cell body and local branches of the axons, called axon collaterals. Before the myelination of certain areas supports connections between neighboring neurons, a strengthening of connections occurs locally through the B-system. Pulvermüller and Schumann (1994:713) assumed that the acquisition of the phonological and syntactic system is very easy in life but becomes increasingly difficult with age because these domains are related to connections within a limited cortical area. Further, semantics, pragmatics, and vocabulary are less affected by maturational constraints as these domains of language are related to the A-system, including the higher association areas.
Other suggestions concerning cerebral constraints and second language acquisition range from metabolic differences (Pulvermüller and Schumann, 1994, p. 710), to the thickening of the corpus callosum (Seliger, 1978) and the previously mentioned lateralization (Lenneberg, 1967).
Quite in contrast with the suggestions described above, current brain research has provided an enormous amount of evidence uncovered in the past two decades, that the brain never stops changing and adjusting. In fact, research showed that the levels of myelination keep rising into the early twenties, and then flatten out after having doubled in the second decade of life. The process then takes off again in the forties and continues into the mid fifties, accumulating, on average, another increase of fifty percent before leveling off again. This means that myelination continues to change at least into the 4th decade of life.
In this context, the study of Kramer et al. (2004) is worth mentioning. This research group carried out a study on environmental influences on cognitive and brain plasticity during aging. The research emphasized the modifiability of age related changes in cognition and underlying brain function. Interestingly, external factors such as lifestyle, education, occupation, expertise, and fitness have been found to influence the trajectory of cognition from young to old adulthood.
Viewed in this light, it is a definite misconception that the adult brain is in a state of shutdown. The brain grows and continues development through death, provided the right conditions are met.
In addition, the study by Pallier et al. (2003) should be mentioned. These researchers carried out a brain imaging study of language plasticitiy in adults who were born in Korea but adopted by French families in childhood. The central question of the research was to find out whether a second language can generally replace the first. Studying language perception and comprehension using behavioral methods and fMRI the research team found out that the subjects had no conscious memory of Korean. Furthermore, the fMRI data showed no difference in brain activation when the participants heard Korean compared to any other unknown foreign language. Finally, the activated cortical regions responding to French were identical with activation patterns in native French subjects. These findings strongly question the crystallization hypothesis predicting that the later a second language is learned, the more the cortical representations of the second and the first languages will differ.
That is to say, to put the matter in a nutshell, there is still no agreed-upon explanation on the influence of biological factors on second language learning.
184.108.40.206 Socio-Psychological Aspects
As socio-psychological aspects of bilingualism were discussed in detail in my master thesis (Wilscher 2003:33-40), these factors of influence will only be touched upon briefly here. Social-psychological aspects include motivational, affective, attitudinal, input factors, and a general talent for acquiring languages. The field study of my master thesis (Wilscher:2003) clearly revealed that such factors have an enormous influence on the outcome of late second language learning. Furthermore, the relationship between bilinguality and cultural identity was stressed and considered to be reciprocal. The field study and data analysis showed that there is a link between bilingual language proficiency and cultural identity. Hence, it was concluded that a balanced bicultural bilinguality could only be achieved if the characteristics of cultural identity, which are considered to be relevant for the acquisition of the two languages, have a highly positive value for the bilingual’s identity without interference (Wilscher, 2003:40).
Researchers (e.g., Bialystok and Hakuta, 1999) have claimed that children develop a positive attitude towards an L2 language community faster and with more ease than adult learners. It was also stated that children receive more and simpler input than adults. In contrast, Long (1990) explained that one cannot lump together these factors for different outcomes in childadult second language acquisition. For example, especially children can easily be influenced to refuse a language, if a certain group is unwilling to accept it. Furthermore, the simple argument that children receive more input than adults cannot be accepted. Other researchers (e.g., Johnson and Newport, 1989; Oyama, 1978) have shown that motivational factors do not have an impact on ultimate levels of L2 proficiency.
From my own point of view, I am convinced that the influence of sociopsychological factors on late second language acquisition has been underestimated so far. Proceeding on the findings, that maturation plays a crucial role in L1 acquisition, we can be sure that L2 acquisition is indeed influenced by a learners’ maturational state as well. Yet, it would be very astonishing if socio-psychological factors had absolutely no influence on L2 acquisition. Bringing these two approaches together, it may be assumed that there exists an interplay between maturational constraints and socio-psychological factors in terms of second language acquisition. Bon gaerts (1995:45) claimed that non-maturational factors sometimes “compensate for the biological disadvantages of a late start.”
Another study by Moyer (1999), which was previously mentioned, showed that input factors strongly correlate with the levels of ultimate language proficiency in late L2 acquisition. This study showed, among others, that different starting ages after the end of maturation did not correlate with levels of proficiency.
Concerning the talent for learning languages, Ioup et al. claimed that it originates in an “unusual brain organization where a greater proportion of cortex is devoted to language” (1992:92). Furthermore, they suggest that “any apparent exceptions to the CPH will manifest some aspects of the neuropsychological profile that characterize language learning talent” (1992:93).
Although empirical research on the bilingual’s cultural identity and its relation to language proficiency is still scarce, it may be concluded that L2 language proficiency is interrelated with relevant socio-psychological factors.
3.2 Resume of the Literature Review
In spite of the vast body of research, the concept of a critical period for second language acquisition continues to be a controversial topic. The crux of the issue, among others, is that researchers have taken a rather wide range of theoretical positions on the basis of quite different empirical data. As can be seen from the literature review, there are multiple formulations of the critical period hypothesis as it is applied to second language acquisition. These range from a decrease of neural plasticity in the relevant cortical areas with increasing age (e.g., Lenneberg, 1967; Pulvermüller & Schumann, 1994), a loss of access to the language learning faculty, or Universal Grammar (e.g., Eubank & Gregg, 1999), to a gain in information processing capacity that might be ill-suited to the task of language acquisition (Newport, 1991) etc.
- Quote paper
- Dr. phil. Daniela Reichholf-Wilscher (Author), 2006, Bilingualism across the lifespan - A cross linguistic and cross cultural approach, Munich, GRIN Verlag, https://www.grin.com/document/118305