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© Borgis - Postępy Nauk Medycznych 6/2016, s. 419-423
Paulina Przybysz1, 2, *Teresa Jackowska1, 2, Łukasz Obrycki3, Piotr Hartmann1, 2
Speech development in bilingual children**
Rozwój mowy u dzieci dwujęzycznych
1Department of Pediatrics, Centre of Postgraduate Medical Education, Warsaw
Head of Department: prof. Teresa Jackowska, MD, PhD
2Department of Pediatrics, Father Jerzy Popiełuszko "Bielański" Hospital, Independent Public Health Care Institution in Warsaw
Head of Department: prof. Teresa Jackowska, MD, PhD
3Student Research Circle, Department of Pediatrics, Centre of Postgraduate Medical Education, Warsaw
Head of Circle: Piotr Hartmann, MD
Streszczenie
Dzieci dwujęzyczne posiadają umiejętności mówienia w obu językach, które pokrywają większość znaczących obszarów ich życia, pozostając jednocześnie we względnej równowadze. Rozwój mowy dzieci wychowywanych w środowisku dwu- lub wielojęzycznym cechują pewne różnice w porównaniu z ich jednojęzycznymi rówieśnikami. Odrębności charakteryzujące dwujęzyczność, jak np. mieszanie języków, nie stanowią patologii, o ile występują w ściśle określonych okresach. Oceniając rozwój mowy u dzieci dwujęzycznych, należy kierować się takimi samymi zasadami jak w ocenie dziecka jednojęzycznego. Niezależnie od uwarunkowań kulturowych określono kamienie milowe rozwoju językowego, które obowiązują wszystkie dzieci. Dziecko powinno opanować podstawy języka do 4. roku życia, a jego mowa powinna być w tym czasie w całości zrozumiała. Dwujęzyczność nie powoduje opóźnienia rozwoju językowego. W artykule przedstawiono podstawowe różnice w rozwoju mowy u dzieci dwujęzycznych oraz odpowiedzi na najczęściej zadawane w tej kwestii pytania.
Summary
Bilingual children are children whose skills in both languages involve the most significant areas of life and are in relative mutual balance. Speech development of children raised in a bilingual or multilingual environment is different from that of their monolingual equals. The main features of bilinguals, such as language code mixing, do not account for abnormality if they appear within strictly defined periods. To evaluate speech development of a bilingual child, the same rules apply as for assessing a monolingual child. Regardless of the cultural determinants, there are specific milestones of speech development that apply to all children. Every child should master the basic language skills until the age of 4, and its speech at this age should be completely comprehensible. Bilingualism does not cause a delay in speech development. This paper presents the basic differences in the language development of bilingual children as well as the answers to frequently asked questions regarding this issue.
Słowa kluczowe: rozwój mowy, dwujęzyczność.
Introduction
Speech development is a complex and dynamic process, dependent mostly on the child’s age, exposure to language and social interactions. This process is even more complex if the child is raised in a bi- or multilingual environment. In the context of the recently more frequent phenomenon of migration, the number of children exposed to more than one language since birth is constantly growing, alongside with the uncertainties of parents about multilingual upbringing, its impact on the children’s speech and social development. The paper presents the differences in speech development among bilingual children, what aspects should be paid special attention to, what is norm as opposed to what should raise concerns, as well as answers to questions most frequently asked by parents.
Main assumptions:
1. Speech development in bilingual children differs from the speech development of children exposed to only one language at the developmental age.
2. Bilingualism does not cause a delay in language development.
Bilingualism
In order to discuss the issue and analyse the speech development process in bilingual children, it is necessary to refer to a definition of bilingualism. In specialist literature function various descriptions, including mutually inconsistent ones; moreover, parents not always understand their children’s bilingualism in the same way. Altogether, bilingualism a child is bilingual if its skills in both languages concern significant areas of the child’s life, remain in balance, and are mastered at a similar (although not necessarily equal) level in speech and writing. The skill that is characteristic for bilingual persons is the ability to function at ease in both language cultures, including such aspects of communication as gestures, mimics and intonation typical for each language, and, what follows – thinking and expressing emotions in both of languages (1).
Two models of bilingual upbringing are predominant:
– the first model – when the parents use different mother tongues and each one of them speaks to the child in their own language (the child has contact with both languages simultaneously before the age of 3, which is called parallel language acquisition),
– the second model – when the first language of both parents is the same, but the language of the environment is different (in this case, the second language is introduced at a similar scope as the first language, but mostly not before the child starts going to kindergarten or school, that is, after the age of 3 – this is successive language acquisition).
In both cases the child is able to acquire both languages as its native (provided the contact with them is strong enough before the age of 8). The difference is only in the linguistic openness. The child who acquires languages simultaneously, functions in its peer group as a monolingual child, especially since the moment when it is able to easily distinguish the languages (1-5). The level of mastering both languages is changing throughout the course of life, but generally one of the languages becomes the so-called strong language, while the other language becomes the weaker one (1, 2, 5, 6).
Speech development in bilingual children
The basic condition for language development and communication is differentiating the speech sounds coming from the environment (e.g. human sounds vs. inanimate nature) (3). The child has a natural ability to learn any language, but the condition to acquire any one of them is the ability to hear speech (1, 3, 7). A newborn is able to identify the sounds of speech, and during the first year of life this capacity is mastered for the native language. The consequence is a loss of the ability to recognize sounds that are not used while learning the native language, that is, phonemes that are characteristic for other languages. If the child has constant contact with two languages, the sounds characteristic for both of them are preserved, and the accent and typical intonation is acquired (3, 7-10).
Apart from the child’s physical conditions, the whole process of speech development also involves other areas of functioning. In order for this process not to be disturbed, it is necessary that the child’s psychic and socio-emotional development is progressing well. The process of acquiring language takes place in subsequent stages that are the same for all children, irrespectively of the particular language they are raised in. The human mind is prepared to acquire two “first languages” to the same extent as one (4, 6). That is why bilingual children reach the same milestones as monolingual ones, although possibly in a different way (tab. 1) (1, 4, 8, 11).
Tab. 1. Milestones in proper speech and language development
AgeMonolingual childrenBilingual children
1 monthCrying.No differences.
2-6 monthsVowel sequences (cooing, gooing, gurgling).
After 6th monthVowel-consonant sequences (babbling).Phonemes typical for the language spoken in the child’s environment.
1 yearSyllables: “mama”, “papa”, “boom boom”.Starting to understand both languages, children learn words they often hear in both languages and use them synonymously, less than one new word a week.
1 1/2 yearsToddler speech with single-word insertions: “give”, “no”, “car,” etc.
2 yearsTwo-word sentences: “mummy give”, “so what”, “don’t want”. Speech partly comprehensible.Children notice that the words belong to two distinct languages; they use one, simple, childlike grammar. They learn new words every day.
3 years3-5-word sentences. “Vocabulary explosion”.Children distinguish the languages, learn two gram mars. Frequent mixing of the languages. Certain children are able to translate.
 
4 yearsTalking in a conversation, telling stories. Speech fully comprehensible.
5 yearsComplex narration.
Future tense, abstract concepts. Inventing words like “a stealer” (thief).
The first way the child communicates with the environment is cry, which then becomes differentiated, depending on the situation and needs. In the case of speech development, the first attempts to speak take place in the 3rd month of life, in the form of cooing or gurgling, that is, repeated vowel sequence vocalizations in response to the sounds of the environment. At this age the child should also turn its head or eyes towards the source of the sound. This stage is similar for all children, and even deaf children coo (1-3).
About the 6th month of life vowel-consonant combinations occur, called babbling. The child starts reacting to its name and looks at the family member who has uttered its name (1, 3). Deaf children do not babble (1). Babbling smoothly turns into the stage of canonical babbling, when the consonant-vowel sounds form long sequences that are like singing. Both stages takes place between the 6th and 10th month of the child’s life. The child at this age is able to recognise all sounds that occur in human speech and gradually starts specialising in the sounds that are characteristic for its environment – it uses words like “mama”/“dada” – nonspecifically, and understands basic concepts, like “bye-bye”, “don’t” (1-3).
Uttering first words that have concrete meaning usually takes place between the 9th and 12th month of the child’s life, not later than at the age of 18 months. A child brought up in a bilingual environment learns both languages at that time, rather using easy and more frequently heard words (1). This is an undifferentiated stage of “one language”, the same like in monolingual children, however, it consists of two languages (2). About the age of 2 children start to become aware that there are two distinct languages spoken around them (before that, since the 4-5th month, children have been creating two patterns, depending who uses the given language and in what situation, but they have not yet been aware of their distinctness), they learn words in both languages and they use them synonymously (1, 2, 4).
When the so-called “explosion of vocabulary” takes place, which happens in the child’s third year of life, children notice grammar rules and start using them. There occurs a phenomenon that is characteristic for multilingual environments, that is, of mixing languages (1, 3, 5, 6). The child borrows words from one language to the other, constructs utterances based lexical items from both languages and mixes grammatical rules, i.e. when speaking in one language, the child uses syntactic structures characteristic for the other language. At the age of four, the child is able to use the appropriate language to communicate with the given family member or in a given situation. Alongside with an expanding vocabulary, the capacity to express strains of thought using words and acquisition of grammar rules, children gradually mix the languages less and less, and are able to translate them (1-3, 6). Research suggests that the ability to identify selected semantic equivalents in both languages is already observed in children who use as few as 12 words, but full skills in this area require a total distinction of the languages (8).
Regardless of the cultural conditioning, the child should acquire the basic language skills until the age of 4, and by then its speech should be completely understandable (3).
Until about the 8th year of life it is possible to acquire another language at the same level as the native one, including the natural melody (intonation) and the ability to think and feel in this language. Language acquisition at a later age involves different areas of the brain than in childhood, thus, the typical linguistic mistakes made by adults learning a foreign language are very different from the ones made by a small child (1).
Assessment of speech development in a bilingual child
The standards for the diagnosis and therapy of speech development delays in bilingual children have not yet been specified. It is worth noting that apart from the physician’s own sensitivity and experience, the anxiety of the child’s parents is another factor that should awaken the doctor’s interest and need of examining the problem.
Bilingual children usually do not master both languages at the same level. One language is usually more developed, although the development speed of each language may vary (1, 4, 8, 12). Speech development may generally proceed slightly more slowly, although it is not a rule, but it still should remain within the developmental time frames of healthy children (1-5, 8, 11, 13). The key factor in the assessment is the speed of speech development and the time of reaching the specific milestones in this area. Speech is assessed based on the acquisition of both languages in younger children (e.g. the number of words is counted for both languages, not only for one), and based on the stronger language in children who distinguish the languages. There exist features that are specific to bilingualism, such as mixing languages, which are not a pathology in speech development as long as they occur within strictly defined periods of time. For assessing the disorders in speech development of a bilingual child the same diagnostic criteria are used as for the child’s monolingual peer (1-3).
Speech should appear in all children by the 18th month of life, which is a norm also for monolingual children. If a one-year old child does not utter words in any language, it is not a reason to give up bilingualism (1, 2).
Mistakes in pronunciation and grammar are usually not a sign of a speech disorder, but are part of a natural process of acquiring new concepts and structures, especially when the child is simultaneously acquiring two languages that do not stem from related families. This is a result of excessively using newly learnt rules and happens to all children (14).
Mixing languages is a norm in children aged 3-4, and later it should gradually disappear. It should be distinguished from the phenomena of interference and code switching, which are not a pathology at any age and are usually present in multilingual persons. Interference is a visible impact of one language, usually the stronger one, on the other. It involves transferring lexical structures, and as a result, new structures appear, partially wrong at the level of pronunciation, vocabulary or syntax (1, 9). Code switching is a fast switch of language of the given utterance and concerns a word, phrase, sentence or a few sentences. This change is clearly marked, easy to distinguish and consciously made by the speaker. This ability appears about the age of 8 and indicates the child’s high competence in both languages (1).
The structure of the languages among which the child is raised is also of crucial significance. Due to their structure, certain languages require more time to acquire than other ones, which should also be taken into account when assessing speech development. If the languages belong to one family and are similar, they are easier for the child to learn, but more difficult to distinguish, which may result in a longer period of mixing languages. However, if the languages are extremely different, the child will understand the differences between them faster, but extending the range of vocabulary and developing grammatical fluency may take place more slowly (1, 8).
In the sense of the potential of language acquisition, bilingualism does not cause delays or disorders in speech development; however, it may be one of the factors that invoke or intensify the predispositions or the already existing disorders (1, 2). The occurrence of speech disorders in the population is about 4-7% children and is similar for the mono- and multilingual environments (1, 3).
The most frequent concerns about speech development in bilingual children
Cognitive development
The condition for optimal cognitive development is mastering at least one language at a level that is comparable to the child’s monolingual peers. If the child does not learn any of the languages at a level that corresponds to its age, its cognitive development is hindered, which becomes visible at school, where e.g. abstract concepts and complex grammar structures are necessary to function effectively (1, 2). However, certain children are perfectly fluent at both languages in speech and writing, which is especially visible through bilingual education. Studies in Canada and the USA show, nevertheless, that the IQ of bilingual children is comparable to the IQ of monolingual children (1, 15). Certain authors (9, 10) relate bilingualism to the appearance of Alzheimer disease symptoms, which, however, requires further confirmation.
Do bilingual children start speaking later than monolingual ones?
Regardless how many languages there are in the environment the child is raised, speech (consciously uttered words of a specific meaning) should appear not later than in the child’s 18th month of life. Later on, the speed of development may vary for each of the languages. The moment of uttering the first words may be slightly delayed in relation to the child’s monolingual peers, but it should remain within the specified time frames (1, 2, 8). Studies show that the number of words uttered by bilingual children is comparable to the number of words uttered by their monolingual peers (counting all word in both languages, synonyms counted double), with possible slight differences that disappear by the age of 5 (6).
Difficulties at school
Even children with learning problems are able to speak two languages fluently, but their process of learning may be slower (2). If school difficulties occur or intellectual disability of any degree is suspected, the focus should be on speaking to the child in the language of the school it attends, regardless if it is the stronger or weaker language. Preserving the bilingualism does not cause a confusion in the child, but it should be made sure that the child feels comfortable in the language of its environment, especially at the start of its school education (2).
Speech disorders
It is not advisable to monotonously correct the child or excessively stress proper pronunciation, making the impression of unnecessary pressure on the child. The child should rather have an opportunity to hear correct pronunciation and simultaneously observe the mouth movements while the adults are speaking (1). The moment when the child should have learnt all phonemes is the beginning of school education, because a speech impediment hinders the process of learning how to read and write. If there are any disorders, it is necessary to consult a speech therapist. Persistent speech impediments may be very difficult or impossible to correct later on. In order to avoid that, a pediatrician should carry out basic prophylactics, in cooperation with the parents, at routine visits and health check reviews. Depending what language the child speaks, the appropriate specialist is to be consulted in such case.
Advice for parents of bilingual children
1. It is the parents’ decision whether to raise a child in a bilingual environment. The child brought up in such way requires effort and additional care of its parents. There are various myths concerning bilingualism (tab. 2); hence, in order to support their child’s proper speech development, certain advice and recommendations to facilitate this process are worth following.
Tab. 2. Myths concerning bilingual children
Myths
Only exceptionally talented children are able to grow up in a bilingual environment without problems.
Speaking to a child in two different languages causes confusion and the child will never acquire any of them at an adequate degree.
Bilingual children start speaking later than monolingual children.
Bilingual children have problems at school and will never perform at the level of monolingual children.
If a child has problems with pronunciation, grammar or is unwilling to speak, it is a reason to give up bilingualism.
It is possible to acquire a second language like one’s native language only when one has contact with it since birth.
Bilingualism indicates perfect performance of two languages at the same level.
It is enough to play the child stories in a foreign language to make it bilingual.
2. The basic issue in deciding on bilingual upbringing of a child is the choice of the method. It mostly depends on the family situation (the nationality of the parents and the environment), but certain general rules are necessary to be followed. The best way to maintain two languages is to decide to whom or when the child speaks the given language (2). Specialists agree that the method “one person – one language” is the most effective in the situation of families of mixed backgrounds. It is especially important to consequently obey this rule until the 4th year of the child’s life, i.e. until it learns to easily distinguish the two languages (1, 3). Parents may communicate with each other in both languages, without mixing them in the child’s presence, but when addressing the child they should use only the language initially selected.
3. If the home language differs from the language of the environment, it is advisable to provide the child a possibly most early exposure to the language which it will be using in the future and at school. In this situation, the child will learn to distinguish the languages based on the situation when they are used, i.e. to distinguish among sets like “home – playground” or “home – kindergarten”.
4. Each parent should speak to the child using the language they feel the most comfortable with (1, 2, 6). It is best if this is the parent’s mother tongue, correct in terms of grammar and accent. We usually think, feel and express our emotions most freely in our native language. In these situations the verbal message is most consistent with the body language, which is what the relation of the child and the adult is based upon. If the parent communicates with the child in a language they have acquired in adult life, regardless of the level of linguistic competence, they usually maintain the melody of the native language. From a scientific point of view, it is not advantageous for the child to speak to it in two different languages if both parents are of the same nationality and use one mother tongue. In such situation, the most effective is to send the child to a bilingual preschool and support its linguistic education by listening to stories in that language or employing a nanny whose native language is the one the child is learning (1, 2).
5. Parents should not “teach” the child a given language. Language acquisition should come as a natural process. The child should be exposed to the given and see a natural need to communicate in this language (12). If the child sees that it needs a given language for contacts with a given person or environment outside home, it will first capture the sound patterns that are characteristic for that language, and then learn to use it in communication.
6. When addressing the child, parents should not automatically change their style of speaking, oversimplifying the grammar or unnaturally impoverishing the vocabulary. This is not beneficial especially if each one of them speaks a different language. It is advisable to preserve the richness of the language spoken to the child both in terms of the vocabulary as well as grammar and syntax. Otherwise, the child is not given a chance to “make up” for the linguistic competence of the other parent if the first one uses only “motherese” (1, 2). Maintaining a proper level of variety in vocabulary and structures may be aided by reading aloud to the child (the same stories repeatedly, which facilitates the remembering of adjectives, nouns and sentence structures), and when working with older children, reading and re-telling the stories in one’s own words.
Conclusions
The issue of speech development of children exposed to more than one language at their developmental age, whose number is constantly growing, is of interest to many parents and educators. Solid knowledge of pediatricians will allow us not only to dispel the doubts, but first of all to guarantee an early recognition and intervention in the case of the occurrence of any disorders.
To remember
In the context of an appropriate potential for language acquisition, bilingualism does not cause delays in language development. Speech development in bilingual children may proceed more slowly, but it still falls within the time frames of speech development of healthy children (1-3, 6, 7, 14).

**Supported by the Centre of Postgraduate Medical Education in Warsaw grant number 501-1-20-19-16
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otrzymano: 2016-05-04
zaakceptowano do druku: 2016-05-25

Adres do korespondencji:
*Teresa Jackowska
Department of Pediatrics Centre of Postgraduate Medical Education
ul. Marymoncka 99/103, 01-813 Warszawa
tel. +48 (22) 864-11-67
tjackowska@cmkp.edu.pl

Postępy Nauk Medycznych 6/2016
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