Dual language development in early childhood

Introduction

That human beings possess the cognitive capacity to learn one language without experiencing any real burden is widely accepted as fact among people. Conversely, early dual language acquisition in young children is often seen as threat to the child’s language development (Paradis et al 2011). Indeed, some writers often describe the uncertain problematic aspects of the learning stage of bilingualism, and some professionals even discourage parents from pursuing dual language acquisition for their children, in some instances, holding the belief, that it could cause speech delay. This review aims at deconstructing the bilingual myths wildly spread throughout the population which possibly originated from early research in the field, which created a pessimistic general outlook on the topic. In fact, in 1966, in his book “bilingualism and primary education”, John Macnamara argued that language acquisition in bilingual children was impossible to balance due to the proficiency of one language augmenting against the other language proficiency falling behind. Such pessimistic views can be filed under the most influential theory on bilingualism in young children at early research stages: the limited capacity hypothesis. This hypothesis postulates the existence of a limited language capacity for children to acquire two or more languages simultaneously or sequentially.  In this manner, the mentioned hypothesis has contributed to the creation of a detrimental view of early bilingualism being seen as the cause of burdensome language confusion and even speech delay in pre-school and young  school age children. Also, interestingly, some theoreticians have been profoundly fascinated with the idea that bilingual children could show significant differences compared to their monolingual peers on a cognitive level. More specifically, some people believe that bilingualism is a threat to the child’s social, cognitive and personality development (Paradis et al 2011). In support of this opinion are early studies conducted by several scholars among those, Diebold (1968), who concluded that bilingualism could even lead, in extreme cases, to schizophrenia. Such studies were later re-evaluated and it was found that they lacked the appropriate methodology design. For instance, one of the main shortcomings discovered, was comparing the evaluation of bilingual children’s performance when they belonged to opposite socioeconomic stratums. Most importantly, the majority of the bilingual children examined were living in subtractive bilingual environments, a term coined by psychologist Wallace Lambert in 1977, meaning that the acquisition of the majority language was attained at the cost of the loss of the native language.  The overall objective of this critical review is to examine the available evidence in research which reveals that dual language acquisition does not impede a “normal” language development in young children and most significantly it is not a synonym of “deficit” or “disorder”.  It will focus on four discussions points: the relationship between language and cognition, the importance of cross-linguistic influence and code-mixing, the impact of language exposure on bilingual children and finally how long can it really take for school age children to acquire a second language.

Just as adults are, children are unique individuals with many differences

These differences often constitute a challenge for parents but also for educators and even professionals who are not familiar with a specific child’s background. Bilingual young children embody linguistic and cultural variations in addition to those they have in common with monolingual children. These variations enrich the child’s experiences and might even benefit their lives in many ways. However, very often these children are stigmatised by being defined as different, in its negative connotation, and they are treated accordingly, particularly in those communities where monolingual children represent the norm. This comes as no surprise when even the American Family Physician Journal (1999) lists bilingualism along with cognitive disorders as one of the causes provoking speech delay. “A bilingual home environment may cause a temporary delay in the onset of both languages. The bilingual child’s comprehension of the two languages is normal for a child of the same age, however, and the child usually becomes proficient in both languages before the age of five years.”  Beyond the lack of recent empirical research in support of this claim, the citation does not take into consideration diverse factors which have diverse impacts on children such as age. According to Paradis et al (2011) young bilingual children are divided into two groups which need to be distinguished for reasons that will be analysed subsequently. The scholars use the term of “simultaneous bilingual children” referring to those children who have the opportunity to be exposed frequently to both languages from birth or soon after, even though, an equal exposure is fairly difficult to achieve due to a wide range of factors. On the other hand, Paradis et al (2011) employ the term “second language learners” or “sequential or successive bilinguals”  when referring to those children who have already made a considerable advancement towards the acquisition of one language, when they begun the process of acquiring the second language. Even though there is not a net distinction in the child’s development which delineates bilingual from second language acquisition, there is a general consensus among researchers on the cut-off age of three. Such a distinction arises for two crucial reasons; first of all, because the first language vocabulary and grammar can be already well established and cognitive age can also be a variable in second language learning, and secondly because emerging evidence shows that there exist subtle differences in language outcomes when learning does not start at birth or before 3 or four years of age.

Do young children have cognitive limitations which result in a burdensome experience when learning two languages?

One of the main issues in understanding dual language development in both simultaneous bilinguals and sequential learners is undoubtedly the complicated link between language and cognition. Laura Berk provides a useful definition of cognition: “cognition refers to the inner processes and product of the mind that lead to ‘knowing’. It includes all mental activity-attending, remembering, symbolizing , categorizing, planning, reasoning, problem solving, creating and fantasizing” (2003, p.218). Such connection has been widely researched by theoreticians seeking to understand the relationship between language and cognition in specific theoretical frames. Such meticulous research is beyond the scope of this review, in fact, it will suffice to focus on those specific facets regarding two controversial questions which seem to be of extreme concern to parents and professionals alike. Firstly; do young children have cognitive limitations which result in a burdensome experience when learning two languages? Secondly; does dual language learning affect cognitive development? The answers to these questions are of vital importance for parents and professionals who often hold false beliefs and interpret the behaviours of dual language learners that vary from monolingual children as signs of impairment, when instead such behaviours could reflect individual variations present in children, just as they are in adults. A well spread myth on bilingualism, amongst laypeople and some professionals alike is the belief that children experience difficulty because they have limited cognitive language capacity. As previously mentioned, early research contributed to creating a pessimistic view on bilingualism in early childhood by postulating the hypothesis of an existing innate limited language capacity in infants and young children (the limited capacity hypothesis). On the other hand, recent research suggests the existence of a biological ability to acquire two languages without compromising both languages’ development. Even though, the research on dual learning children has been minor compared to the research conducted on monolingual children, the latter reveals important findings that relate to bilingual children to a great extent. Indeed, evidence shows that children are born with significant processing skills which allow them to learn a language at very early development.  Impressively Boysson-Bardies states: “we now know that not only is the brain of the baby not empty, but in a certain sense it is fuller than that of the most brilliant scientist” (1999, p.13). Gerken (2008) provides a review on studies on infants from 6 to 18 months who were tested on their preference of one auditory stimulus against another, with some infants also assessed on their ability to differentiate two types of stimuli based on existing knowledge they had when entering the laboratory. From these studies, it emerges that infants are able to detect a language related input. In addition, there is empirical research which demonstrates that infants’ remarkable auditory discriminatory and memory skills after birth are influenced by language experiences in the womb.  Bosch and Sebastian-Galles (2001)studied language differentiation abilities in 4 month old infants exposed to Spanish and Catalan and discovered that their discrimination skills were similar, therefore, they concluded that reduced exposure to each language did not delay the appearance of the language differentiation ability in these learners. Further research reveals that infants have the capacity to discriminate individual language sounds described with the term of phonetic segments. Most recently Petitto et al (2011) carried out a neuroimaging experiment to examine the phonetic processing in bilingual and monolingual babies. She divided the babies in two age groups with younger babies with ages between 4-6 months and older babies between 10-12 months. The scholar found out not only that the phonetic processing in infants is achieved with the same language-specific brain areas as in adults, but also that the phonetic processing in the two groups took place with significant timing differences. Fascinatingly, Petitto et al (2011) observed in older bilingual babies a robust neural and behavioural  sensitivity to Non-Native phonetic in contrast to monolingual babies of the same age who could no longer make such differentiations. She therefore advanced “The Perceptual Wedge Hypothesis” with the “wedge” corresponding to the increased neural and computational demands of language exposure and processing, which resulted in strengthening language analyses abilities across two language systems through an agile linguistic processing in general. It is fascinating how the human language processing is dominated by biological factors, but can at the same time be altered by experiences dictated by the outside environment. Petitto et al (2011) concludes by supporting the existence of language advantages in young bilingual infants who are subject to an early bilingual exposure. In contrast to the general belief that exposure to a second or additional language causes language delay, such a study busts the related and wide-spread myth by demonstrating that early bilingual exposure does not in fact hamper the developing bilingual child. In conclusion, both researches, in bilinguals and monolingual infants support the view of the capacity in infants to analyse and make sense of language input, with older bilinguals acquiring an impressive language processing ability. Moreover, a significant way to determine whether dual language learning is burdensome for young children is to examine the language development milestones in simultaneous bilingual. If dual language learning cognitive limitations did exist in infants, it would be expected that young children would be affected by delays in early milestones. Even though, simultaneous bilingual children show differences, compared to monolingual children, in their babbling and first word combinations, these do not present delays in their language development. Such differences appear to be the result of the intensity of the exposure to both languages and could also be influenced by diverse factors. Studies on babbling and lexical development in infants and toddlers showed that bilingual children produce their first words at approximately the same age as their monolingual peers. Even investigations on bimodal language learning resulted in no delay compared to monolingual milestones. Indeed, Petitto and her colleagues (2001), studied a sample of hearing children who were learning spoken French and sign language at the same time. Fascinatingly, the investigation revealed that the first words, first two-words combinations and the acquisition of the first 50 words were attained by three of the bilingual children examined in the same time frame as monolingual children. In sum, research on early milestones development shows that bilingual children do not necessarily experience difficulty. These findings do not, however, imply that simultaneous bilingual children experience the same language development patterns as monolingual do and certainly do not match monolingual children in every aspect. Nevertheless, these differences do not translate into deficits or disorders as they do not cause significant language delays. Parents and professionals should be aware that substantial delays in early milestones are often an initial warning that a child might present a language disorder.

General intelligence and second language learning

Another aspect related to the relationship between language and cognition that helps in understanding the capacities that dual learning children possess, is the connection between general intelligence and second language learning. General intelligence in this context refers to those skills that children need to be successful in school such as analytical thinking, problem solving and creativity (Paradis et al 2011). These kind of abilities are usually assessed by IQ tests, yet this idea of intelligence is controversial and totally criticised by some individuals, however, it appears to be broadly accepted among the majority of people.  The link between general intelligence and second language learning is of particular importance to researchers as parents and educators are mostly concerned that children with  levels of intelligence below the average are not able to learn a second language and that the introduction of another language will be so intellectually challenging that it will damage their “first” language development. Paradis et al 2011 dispel this myth by asserting that empirical research has proven that children with intelligence below the norm, score as their monolingual peers with the same low level of intelligence in programs designed for foreign language learning. General intelligence tests are focused to examine those skills as already mentioned that will be necessary for the child’s academic success. In fact, the children who usually obtain high scores in these tests are able to achieve high scores in reading and writing tests. Conversely, general intelligence test do not seem to have high correlations to the acquisition of oral language and listening abilities whose development is linked to social interaction. This could be due to the influence that other factors have on children’s daily communication. In fact, regardless of their intellectual capacity, young children are able to acquire a second language if a necessary language exposure is experienced. Nevertheless, some children can be slower as they might have a lower language aptitude or they could have been affected by traumatic experiences such as food deprivation and post-war shock, which is the case with most refugee children.  It is of crucial importance for professionals to analyse the social and personal circumstances concerning children having difficulties in learning a second language in order to assess the situation correctly. The advances made in early childhood bilingual research lay in the research methods employed which vary considerably from the ones used at early stages. Indeed, most recent research has focused on the study on bilingual children raised in an additive bilingual environment where the child is stimulated and supported in the acquisition of both languages, in contrast to children brought up in subtractive bilingual environments where the child acquires the dominant language and gives up their first language. The latter is the case of immigrant children, the children or grandchildren of immigrants, but also of children who speak an indigenous language. Additive bilingualism is particularly beneficial to children as it supports dual cultural identities, in this way children will enjoy both cultures and will keep a sense of belonging to both communities of the languages spoken. A major shift in research was made by Peal and Lambert (1962), who corrected the many methodology shortcomings of earlier studies and found out that the bilingual group they examined, showed several cognitive advantages compared to the monolingual group. Most recently a prominent researcher in the field, Ellen Bialystok (2001, 2010, 2012), found evidence of advantages in bilingual children linked to metalinguistic awareness; the skill to ponder and handle the elements of language independently of their communicative use. Her research has concentrated on bilinguals who have a high command of both languages and use them regularly, proposing that low levels of bilingual proficiency or usage are inadequate to produce these cognitive advantages.  She refers to such advantages as “executive control functions” which consist of activation, selection, inhibition and coordination of information during the solving of conflicts or planning. In other words, Bialystok has argued that such cognitive advantages are given by the use of selective attention and inhibition functions that highly proficient bilinguals employ in order to channel misleading information, sequentially inhibited to avoid interference between two language systems.  Furthermore, Bialystok and Barac (2012) studied a total of 104 six year old children belonging to diverse groups English monolinguals, Chinese-English bilinguals, Spanish-English bilinguals and French-English bilinguals; all the children had equivalent general cognitive level, psychomotor speed and socio economic status (SES). The four groups were analysed and compared in their ability to carry out three verbal tasks, and one non-verbal executive control task, in order to study the generality of the bilingual effects on development. Even though, the bilingual groups presented several differences in language similarity, cultural background, and language of schooling, they all performed alike in the executive control task and outperformed monolinguals. On the other hand, only those bilinguals whose language of instruction was the same as the language of testing, attained the best performance on verbal tasks. These results endorse the assertion that bilingualism acts independently of those variables exhibited in the investigation. Bialystok et al (2004) also demonstrated that the cognitive advantages related to dual language input and learning do not affect only children, but also adults. In addition, the scholars found out in their study in 2007, that the onset of dementia, in the case of bilingual and monolingual patients with the same clinical diagnosis, was delayed by 4 years in the bilingual patients. In summation, contemporary research has demonstrated that results vary, showing at times advantages for bilinguals, other times advantages for monolinguals and some other times no difference between bilinguals and monolinguals. These findings are of particular interest as they dismiss the simplistic idea that bilingualism causes good or bad effects unconditionally. Further, they help to dispel those bilingual myths which have led to a pessimistic view on the subject; indeed, for too long bilingual children have been considered to be not typically developing if they showed any differences in their development compared to monolingual children. Parents and educators should therefore consider the advantages that can derive from dual language learning in early development.

References

Berk, L. (2003). Child development. Toronto: Pearson Education Canada.

Bialystok, E. (2001). Bilingualism in development: Language, literacy, and cognition. New York: Cambridge University Press.

Bialystok, E. (2009). Bilingualism: The good, the bad, and the indifferent. Bilingualism: Language and Cognition, 12,pp 311, doi:10.1017/S1366728908003477

Bialystok, E., Barac, R.(2012). Bilingual Effects on Cognitive and Linguistic Development:Role of Language, Cultural Background, and Education. Child development, 83,2, 413-422

Bialystok, E., Barac, R., Blaye, A., Poulin-Dubois, D. (2010). Word Mapping and Executive Functioning in Young Monolingual and Bilingual Children. Journal of cognition and development, 11(4):485–508.

Bialystok, E., Craik, F.I.M., &Freedman, M. (2007). Bilingualism as protection against the onset of symptoms of dementia. Neuropsychologia, 45, 459-464.

Bialystok, E., Craik, F.I.M., Klein, R., & Viswanathan, M. (2004). Bilingualism, aging, and cognitive control. Psychology and Aging, 19, 290-303.

Bosch, L., & Sebastian-Galles, N. (2001). Early language differentiation in bilingual infants. In J. Cenoz & F. Genesee (Eds.), Trends in bilingual acquisition (pp.71-94). Amsterdam: John Benjamins.