Bimodal Bilinguals Research Articles

Second language experience modulates functional brain network for the native language production in bimodal bilinguals

The functional brain network of a bilingual's first language (L1) plays a crucial role in shaping that of his or her second language (L2). However, it is less clear how L2 acquisition changes the functional network of L1 processing in bilinguals. In this study, we demonstrate that in bimodal (Chinese spoken-sign) bilinguals, the functional network supporting L1 production (spoken language) has been reorganized to accommodate the network underlying L2 production (sign language). Using functional magnetic resonance imaging (fMRI) and a picture naming task, we find greater recruitment of the right supramarginal gyrus (RSMG), the right temporal gyrus (RSTG), and the right superior occipital gyrus (RSOG) for bilingual speakers versus monolingual speakers during L1 production. In addition, our second experiment reveals that these regions reflect either automatic activation of L2 (RSOG) or extra cognitive coordination (RSMG and RSTG) between both languages during L1 production. The functional connectivity between these regions, as well as between other regions that are L1- or L2-specific, is enhanced during L1 production in bimodal bilinguals as compared to their monolingual peers. These findings suggest that L1 production in bimodal bilinguals involves an interaction between L1 and L2, supporting the claim that learning a second language does, in fact, change the functional brain network of the first language.

Bilingual processing of ASL–English code-blends: The consequences of accessing two lexical representations simultaneously

Bilinguals who are fluent in American Sign Language (ASL) and English often produce code-blends – simultaneously articulating a sign and a word while conversing with other ASL–English bilinguals. To investigate the cognitive mechanisms underlying code-blend processing, we compared picture-naming times (Experiment 1) and semantic categorization times (Experiment 2) for code-blends versus ASL signs and English words produced alone. In production, code-blending did not slow lexical retrieval for ASL and actually facilitated access to low-frequency signs. However, code-blending delayed speech production because bimodal bilinguals synchronized English and ASL lexical onsets. In comprehension, code-blending speeded access to both languages. Bimodal bilinguals’ ability to produce code-blends without any cost to ASL implies that the language system either has (or can develop) a mechanism for switching off competition to allow simultaneous production of close competitors. Code-blend facilitation effects during comprehension likely reflect cross-linguistic (and cross-modal) integration at the phonological and/or semantic levels. The absence of any consistent processing costs for code-blending illustrates a surprising limitation on dual-task costs and may explain why bimodal bilinguals code-blend more often than they code-switch.

Can experience with co-speech gesture influence the prosody of a sign language? Sign language prosodic cues in bimodal bilinguals

In this paper the prosodic structure of American Sign Language (ASL) narratives is analyzed in deaf native signers (L1-D), hearing native signers (L1-H), and highly proficient hearing second language signers (L2-H). The results of this study show that the prosodic patterns used by these groups are associated both with their ASL language experience (L1 or L2) and with their hearing status (deaf or hearing), suggesting that experience using co-speech gesture (i.e. gesturing while speaking) may have some effect on the prosodic cues used by hearing signers, similar to the effects of the prosodic structure of an L1 on an L2.

Structural plasticity of the left caudate in bimodal bilinguals

Bilinguals need an effective neural mechanism to select and control their languages for successful communication. Recent evidence indicates that the left caudate nucleus (LCN) is a critical part of this mechanism. Here we show that bimodal bilinguals, who use spoken and sign languages, have greater grey matter volume (GMV) in the head of the LCN as compared to monolinguals. We also found higher functional activation of this region in bimodal bilinguals when they switched between sign language and spoken language compared to when they did not switch languages. Furthermore, GMV was positively correlated with the magnitude of the switching effect in the head of the LCN. These findings indicate that for bimodal bilinguals, the LCN is shaped by bilingualism both anatomically and functionally.

Hearing, Mother Father Deaf: Hearing People in Deaf Families (review)

Hearing, Mother Father Deaf: Hearing People in Deaf Families, ed. Michele Bishop and Sherry L. Hicks (Washington, D. C: Gallaudet University Press, 2008, 340 pp., $85.00, ISBN 978-1563683978). THIS SEMINAL book provides an in-depth look at language use drawn from several studies on hearing bimodal bilinguals (hearing individuals with Deaf parents, also known as Codas). This volume is significant not only because of the research but also because the editors selected a range of international studies that provide variation in the languages and issues discussed. The chapters in this volume will appeal to researchers, educators, linguists, those who identify as Codas, and those who have deaf parents but do not identify with the Coda label. Hearing, Mother Father Deaf is divided into three parts: bimodal bilingualism in adults; Koda (kids of deaf parents); and coda identity and experience. The organization of the book flows nicely: Content in one chapter provides information that is useful for understanding later chapters. The studies range from controlled experiments to reports of personal experiences or anecdotal evidence. In their introduction, Bishop and Hicks provide an extensive review of issues relevant to the Deaf community and that affect Codas. Following the introduction, the chapters in the first section are Bimodal Bilingualism (Emmorey, Borinstein, Thompson, and Gollan), The Face of Bimodal Bilingualism: ASL Grammatical Markers Are Produced When Bilinguals Speak to English Monolinguals (Pyers and Emmorey), and Coda Talk: Bimodal Discourse among Hearing, Native Signers (Bishop and Hicks). These chapters focus on adult ASLEnglish hearing bimodal bilinguals and examine a specific type of bilingualism in which both languages can be produced at the same time due to the bimodal nature of the languages. In part II the focus shifts to younger children of Deaf parents, Kodas. These chapters explore issues related to the languages used by Kodas in three countries, NGT-Dutch, ASL-English, and DGS-German. The chapter titles are Bimodal Language Acquisition in Kodas (Van den Bogaerde and Baker); Eyes over Ears: The Development of Visual Strategies by Hearing Children of Deaf Parents (Mather and Andrews), and Sociolinguistic Aspects of the Communication between Hearing Children and Deaf Parents (Wilhelm) . Part III has only one chapter, Brazilian Codas: Libras and Portuguese in Contact Zones, by Muller de Quadros and Masutti. The three chapters in part IV share insights into Coda identity and experience. The chapters are Exploring Linguistic and Cultural Identity: My Personal Experience (Napier); Virgilean Guides: Esthetic Subjects in Coda Autobiographies (Ataman); and Characteristics of the Coda Experience in 21st-century Contemporary Culture (Adams). The articles in this section are about hearing individuals with deaf parents who use BSL, Auslan, DGS, and/or ASL. In the remainder of this review, I provide an overview of the information reported in each chapter but encourage readers to read each chapter in its entirety. Although a few sentences in the book are confusing due to typing errors and editing, the studies presented in this volume provide information and insight into a group that has much to offer toward a better understanding of bilingualism and biculturalism, first and second language acquisition, how the brain works with languages, language attitudes, and how some people navigate between the hearing and the deaf worlds. Part I. Bimodal Bilingualism in Adults By studying adult bimodal bilinguals, the researchers in this section provide insight into code blending and language suppression. In the first chapter, Emmorey et al. propose a model of hearing bimodal/ bilingual language production. They report on a study in which they examined conversations and elicited narratives for code blends and code switches in order to determine the characteristics of each. The authors discuss code blending, code switching, and language suppression or language selection. …

Happen Can’t Hear: An Analysis of Code-Blends in Hearing, Native Signers of American Sign Language

Happen Can’t Hear:An Analysis of Code-Blends in Hearing, Native Signers of American Sign Language Michele Bishop (bio) Hearing native signers often learn sign language as their first language and acquire features that are characteristic of sign languages but are not present in equivalent ways in English (e.g., grammatical facial expressions and the structured use of space for setting up tokens and surrogates). Previous research has indicated that bimodal bilinguals draw heavily on American Sign Language (ASL) discourse structures even while predominantly speaking (Emmorey, Borinstein, and Thompson 2003; Bishop and Hicks 2005; Bishop et al. 2006; Pyers and Emmorey 2008). This article analyzes the way in which bimodal bilinguals (hereafter referred to as children of deaf adults, or Codas) simultaneously draw on both ASL and English. Data presented herein indicate that Codas exploit the integration of two grammars, as well as extragrammatical features (e.g., eye gaze, use of space) that are crucial to meaning due to the presence of ASL in their spoken English discourse and its influence on that discourse (Bishop and Hicks 2005; Bishop et al. 2006). These extragrammatical features express meaning in ways that far exceed the capabilities of grammar alone (Liddell 2003). The addition of a signed language to bilingualism studies adds interesting dimensions, especially with regard to native signers who have [End Page 205] both English and ASL as their first language (the participants of this research). The ability to produce aspects of two languages simultaneously is unprecedented in the area of spoken language bilingualism: For unimodal (speech-speech) bilinguals, the vocal tract is used for output in both languages. In contrast, for bimodal (speech-sign) bilinguals, there are two output channels: the vocal tract and the hands. In addition, unimodal bilinguals perceive both languages by the same sensory system (audition), whereas for bimodal bilinguals one language is perceived auditorily and the other is perceived visually. (Emmorey, Borinstein, and Thompson 2003) The term code-blending is also known as code-mixing in the literature, although the terms have quite different meanings when describing simultaneous utterances in bimodal output as opposed to sequential ones in unimodal output. Bimodality, therefore, offers researchers a new way of observing the alternation between, and the simultaneous production of, two very typologically distinct languages, in this case English and ASL. This simultaneous bimodal output should not be analyzed on a strictly grammatical level because meaning is conveyed through structures that are sufficiently independent of the grammar. Applying morphosyntactic criteria to determine a base language will not suffice when the simultaneous bimodal utterances are grammatically correct in both languages. Rather, it would be more productive to determine how each language contributes meaning to the overall utterance. While this is a vastly different approach from theoretical modes such as the matrix language frame model proposed by Myers-Scotton (1993), it is a crucial one because a matrix language is not easily determined for some code-blends. Van den Bogaerde and Baker’s (2005) approach, on the other hand, classifies code-blended utterances on the basis of the entire proposition. They explore the ways in which Dutch and Dutch Sign Language (Nederlandse Gebarentaal; hereafter NGT) each contributes meaning in code-blended utterances in Deaf mother/hearing child dyads. In this analysis, code-blends are classified according to van den Bogaerde and Baker’s model. For the purposes of analysis, the code-blends are categorized into two groups, semantically equivalent (the two utterances express equivalent meaning) and semantically [End Page 206] nonequivalent (each language contributes a complementary but nonequivalent meaning). The data indicate that, with the classification of semantically nonequivalent propositions, classifications beyond those described by van den Bogaerde and Baker are created and described (i.e., evaluative and elaborative code-blends). Apparently these additional categories, which derive from the present data, are directly due to the differences in complexity between the adult data of this research and the data collected from children under five years of age in van den Bogaerde and Baker’s research. The goal of this article, therefore, is to determine what kinds of code-blends are used in naturalistic discourse and to devise a means to categorize them. The data are classified according to the four...

Co-speech gesture in bimodal bilinguals

The effects of knowledge of sign language on co-speech gesture were investigated by comparing the spontaneous gestures of bimodal bilinguals (native users of American Sign Language and English; n=13) and non-signing native English speakers (n=12). Each participant viewed and re-told the Canary Row cartoon to a non-signer whom they did not know. Nine of the thirteen bimodal bilinguals produced at least one ASL sign, which we hypothesise resulted from a failure to inhibit ASL. Compared with non-signers, bimodal bilinguals produced more iconic gestures, fewer beat gestures, and more gestures from a character viewpoint. The gestures of bimodal bilinguals also exhibited a greater variety of handshape types and more frequent use of unmarked handshapes. We hypothesise that these semantic and form differences arise from an interaction between the ASL language production system and the co-speech gesture system.

The Source of Enhanced Cognitive Control in Bilinguals

Bilinguals often outperform monolinguals on nonverbal tasks that require resolving conflict from competing alternatives. The regular need to select a target language is argued to enhance executive control. We investigated whether this enhancement stems from a general effect of bilingualism (the representation of two languages) or from a modality constraint that forces language selection. Bimodal bilinguals can, but do not always, sign and speak at the same time. Their two languages involve distinct motor and perceptual systems, leading to weaker demands on language control. We compared the performance of 15 monolinguals, 15 bimodal bilinguals, and 15 unimodal bilinguals on a set of flanker tasks. There were no group differences in accuracy, but unimodal bilinguals were faster than the other groups; bimodal bilinguals did not differ from monolinguals. These results trace the bilingual advantage in cognitive control to the unimodal bilingual's experience controlling two languages in the same modality.

Dual language use in sign-speech bimodal bilinguals: fNIRS brain-imaging evidence

The brain basis of bilinguals’ ability to use two languages at the same time has been a hotly debated topic. On the one hand, behavioral research has suggested that bilingual dual language use involves complex and highly principled linguistic processes. On the other hand, brain-imaging research has revealed that bilingual language switching involves neural activations in brain areas dedicated to general executive functions not specific to language processing, such as general task maintenance. Here we address the involvement of language-specific versus cognitive-general brain mechanisms for bilingual language processing. We study a unique population, bimodal bilinguals proficient in signed and spoken languages, and we use an innovative brain-imaging technology, functional Near-Infrared Spectroscopy (fNIRS; Hitachi ETG-4000). Like fMRI, the fNIRS technology measures hemodynamic change, but it is also advanced in permitting movement for unconstrained speech and sign production. Participant groups included (i) hearing ASL–English bilinguals, (ii) ASL monolinguals, and (iii) English monolinguals. Imaging tasks included picture naming in “Monolingual mode” (using one language at a time) and in “Bilingual mode” (using both languages either simultaneously or in rapid alternation). Behavioral results revealed that accuracy was similar among groups and conditions. By contrast, neuroimaging results revealed that bilinguals in Bilingual mode showed greater signal intensity within posterior temporal regions (“Wernicke’s area”) than in Monolingual mode. Significance: Bilinguals’ ability to use two languages effortlessly and without confusion involves the use of language-specific posterior temporal brain regions. This research with both fNIRS and bimodal bilinguals sheds new light on the extent and variability of brain tissue that underlies language processing, and addresses the tantalizing questions of how language modality, sign and speech, impact language representation in the 7brain.

The Face of Bimodal Bilingualism

Bimodal bilinguals, fluent in a signed and a spoken language, provide unique insight into the nature of syntactic integration and language control. We investigated whether bimodal bilinguals who are conversing with English monolinguals produce American Sign Language (ASL) grammatical facial expressions to accompany parallel syntactic structures in spoken English. In ASL, raised eyebrows mark conditionals, and furrowed eyebrows mark wh-questions; the grammatical brow movement is synchronized with the manual onset of the clause. Bimodal bilinguals produced more ASL-appropriate facial expressions than did nonsigners and synchronized their expressions with the onset of the corresponding English clauses. This result provides evidence for a dual-language architecture in which grammatical information can be integrated up to the level of phonological implementation. Overall, participants produced more raised brows than furrowed brows, which can convey negative affect. Bimodal bilinguals suppressed but did not completely inhibit ASL facial grammar when it conflicted with conventional facial gestures. We conclude that morphosyntactic elements from two languages can be articulated simultaneously and that complete inhibition of the nonselected language is difficult.

The bimodal bilingual brain: Effects of sign language experience

Bimodal bilinguals are hearing individuals who know both a signed and a spoken language. Effects of bimodal bilingualism on behavior and brain organization are reviewed, and an fMRI investigation of the recognition of facial expressions by ASL-English bilinguals is reported. The fMRI results reveal separate effects of sign language and spoken language experience on activation patterns within the superior temporal sulcus. In addition, the strong left-lateralized activation for facial expression recognition previously observed for deaf signers was not observed for hearing signers. We conclude that both sign language experience and deafness can affect the neural organization for recognizing facial expressions, and we argue that bimodal bilinguals provide a unique window into the neurocognitive changes that occur with the acquisition of two languages.

Multilingualism and sign languages: from the Great Plains to Australia

12th Volume in the in Deaf Communities Series The latest entry in the Sociolinguistics in Deaf Communities series continues to mine the rich resources found in signing communities throughout the world. Divided into four parts, this collection features 16 internationally renowned linguistics experts whose absorbing studies reflect an astonishing range of linguistic diversity. The sole essay in Part One: Multilingualism describes historic and contemporary uses of North American Indian Sign Language. Part Two: Language Contact examines language-contact phenomena between Auslan/English interpreters and Deaf people in Australia, and the features of bimodal bilingualism in hearing, Italian, native signers. Part Three: Variation reports the results of a study on location variation in Australian Sign Language. Part Four: Discourse Analysis begins with an analysis of how deaf parents and their hearing toddlers establish and maintain sight triangles when conducting signed conversations. The ensuing chapter explores the use of evaluation within an informal narrative in Langue des Signes Quebecoise. The final chapter explicates how a signer depersonalizes the concept of self in an American Sign Language narrative through the use of signs for he and I.

Orange Eyes: Bimodal Bilingualism in Hearing Adults from Deaf Families

Different aspects of bilingualism have been studied all over the world, and the studies have looked at a wide range of topics in spoken- language bilinguals such as patterns of code switching, the role of code switching in community life, the success or failure of bilingual education, second-language learning and gender, as well as many other issues focusing on single-modality bilinguals. These studies are often not applicable to studies of bimodal bilingualism, in which the subjects know a sign language from birth and the spoken language of the larger, hearing society. The study of bilingualism in hearing people from deaf families offers an opportunity to analyze the way that native users of both a signed and a spoken language combine aspects of both languages simultaneously (code blending). The lower status of American Sign Language (ASL) in relation to English may also contribute to how bimodal bilinguals view and use their languages. Unlike spoken-language bilinguals, who must stop one language before beginning another, a bimodal bilingual is able to speak and sign at the same time. This linguistic capability informs and expands the field of bilingualism as well as areas such as discourse analysis and the role of code blending as a cultural identifier. This preliminary research focuses on emails taken from a forum on the Internet for hearing people with deaf parents. Two hundred and seventy five lines from one hundred emails were collected and analyzed. The study shows evidence of strong grammatical influence from ASL in these emails (an absence of overt subjects, overt objects, determiners, copulas, and prepositions) as well as unique structures (nonstandard verb inflections, overgeneralization of the letters, and syntactic calquing). There is also a strong tendency to use English to �describe� an ASL sign (i.e., �My father fork-in-throat�). The meaning of the sign fork-in-throat is �stuck,� but the bilingual chooses to use the visual description of the sign instead of the lexical equivalent in English (note the absence of the copula). The overall results of this analysis are compared to Internet Relay Chat and TDD writings.