The bilingual brain: bilingual aphasia.

Since most people in the world know more than one language, bilingual aphasia is an important line of research in clinical and theoretical neurolinguistics. From a clinical and ethical viewpoint, it is no longer acceptable that bilingual aphasics be assessed in only one of the languages they know. Bilingual aphasic patients should receive comparable language tests in all their languages. In the present work, language recovery of 20 bilingual Friulian-Italian aphasics was investigated. Thirteen patients (65%) showed a similar impairment in both languages (parallel recovery), four patients (20%) showed a greater impairment of L2, while three patients (15%) showed a greater impairment of L1. Despite the many hypotheses advanced to account for nonparallel recovery, none of them seems to provide satisfactory explanations. The study of bilingual aphasics with parallel impairment of both languages allows us to verify the hypothesis whereby grammatical disorders in aphasia depend on the specific structure of each language. As far as rehabilitation programs for multilingual aphasics are concerned, several questions have been raised, many of which still need a satisfactory answer.     

Cross-language lexical connections in the mental lexicon: evidence from a case of trilingual aphasia

Despite anecdotal data on lexical interference among the languages of multilingual speakers, little research evidence about the lexical connections among multilinguals' languages exists to date. In the present paper, two experiments with a multilingual speaker who had suffered aphasia are reported. The first experiment provides data about inter-language activation during natural conversations; the second experiment examines performance on a word-translation task. Asymmetric patterns of inter-language interference and translation are evident. These patterns are influenced by age of language learning, degree of language recovery and use, and prevalence of shared lexical items. We conclude that whereas age of language learning plays a role in language recovery following aphasia, the degrees of language use prior to the aphasia onset and of shared vocabulary determine the ease with which words are accessed. The findings emphasize the importance of patterns of language use and the relations between the language pair under investigation in understanding lexical connections among languages in bilinguals and multilinguals.     

Analyzing the Rate at Which Languages Lose the Influence of a Common Ancestor

Analyzing the rate at which languages change can clarify whether similarities across languages are solely the result of cognitive biases or might be partially due to descent from a common ancestor. To demonstrate this approach, we use a simple model of language evolution to mathematically determine how long it should take for the distribution over languages to lose the influence of a common ancestor and converge to a form that is determined by constraints on language learning. We show that modeling language learning as Bayesian inference of n binary parameters or the ordering of n constraints results in convergence in a number of generations that is on the order of n log n. We relax some of the simplifying assumptions of this model to explore how different assumptions about language evolution affect predictions about the time to convergence; in general, convergence time increases as the model becomes more realistic. This allows us to characterize the assumptions about language learning (given the models that we consider) that are sufficient for convergence to have taken place on a timescale that is consistent with the origin of human languages. These results clearly identify the consequences of a set of simple models of language evolution and show how analysis of convergence rates provides a tool that can be used to explore questions about the relationship between accounts of language learning and the origins of similarities across languages.     

The effect of associative strength on priming in the cerebral hemispheres

Recent studies have suggested that semantic memory is more diffusely organized in the right hemisphere of the brain and that words directed to this hemisphere are more likely to activate meanings distantly related to the input. It is argued that this model of language processes predicts that variations in the associative strength of word pairs should give rise to different patterns of priming in each hemisphere. Specifically, the right hemisphere should exhibit relatively more facilitation than the left in response to weaker associative relationships, whereas the left hemisphere should exhibit relatively more facilitation than the right in the context of stronger relationships. This study varied the strength of the semantic association between prime and target in a divided visual field priming procedure. The results were unequivocal in demonstrating similar associative strength functions in each hemisphere, under conditions that encouraged either automatic or controlled processing. Visual field differences in absolute RTs to words and in magnitude of facilitation effects support the claim that the data collected in this study are veridical with respect to priming processes in the hemispheres. It is suggested that current models of hemispheric language processes require further refinement.     

Left hemisphere language lateralization in bilinguals and monolinguals

Tachistoscopic studies of lateralization in bilinguals suggest that there is a greater degree of right hemisphere involvement in their processing of language than is typically found in monolinguals. However, most of the studies reviewed failed to control the sex, handedness, and degree of fluency of the subjects and did not include a monolingual comparison group. The present study used adult right-handed males (Portuguese-English bilinguals and English-speaking monolinguals) in a tachistoscopic word-reading task. In Experiment 1, the words from the bilinguals’ two languages were presented in mixed blocks, while in Experiment 2, they were presented in separate blocks. The results were: (1) a similar level of left hemisphere advantage for language in the bilingual and the monolingual groups, (2) no evidence of greater heterogeneity of asymmetry patterns in bilinguals, and (3) a significant correlation (r=.61) for lateralization levels of the bilinguals’ two languages. These results indicate that language is processed primarily in the left hemisphere of both bilinguals and monolinguals.     

Direct and indirect effects of multilingualism on novel language learning: An integrative review

Accumulated recent research suggests that prior knowledge of multiple languages leads to advantages in learning additional languages. In the current article, we review studies examining potential differences between monolingual and multilingual speakers in novel language learning in an effort to uncover the cognitive mechanisms that underlie such differences. We examine the multilingual advantage in children and adults, across a wide array of languages and learner populations. The majority of this literature focused on vocabulary learning, but studies that address phonology, grammar, and literacy learning are also discussed to provide a comprehensive picture of the way in which multilingualism affects novel language learning. Our synthesis indicates two avenues to the multilingual advantage including direct transfer of prior knowledge and prior skills as well as indirect influences that result from multilingual background and include more general changes to the cognitive-linguistic system. Finally, we highlight topics that are in need of future systematic research.     

Dissociating language and word meaning in the bilingual brain

How do bilingual (or multilingual) persons keep different languages apart and switch between them as needs arise? Crinion et al. have used an ingenious method to dissociate brain regions sensitive to word meaning from those sensitive to the combination of meaning and language. This work should stimulate further research examining the role of subcortical areas in language processing and in context-appropriate language production.     

The cognitive neuroscience of signed language

The present article is an assessment of the current state of knowledge in the field of cognitive neuroscience of signed language. Reviewed lesion data show that the left hemisphere is dominant for perception and production of signed language in aphasics, in a fashion similar to spoken language aphasia. Several neuropsychological dissociations support this claim: Non-linguistic visuospatial functions can be dissociated from spatial functions and general motor deficits can be dissociated from execution of signs. Reviewed imaging data corroborate the lesion data in that the importance of the left hemisphere is re-confirmed. The data also establish the role of the right hemisphere in signed language processing. Alternative hypotheses regarding what aspects of signed language processing are handled by the right hemisphere are currently tested. The second section of the paper starts by addressing the role that early acquisition of signed and spoken language play for the neurofunctional activation patterns in the brain. Compensatory cognitive and communicative enhancements have also been documented as a function of early sign language use, suggesting an interesting interaction between language and cognition. Recent behavioural data on sign processing in working memory--a cognitive system important for language perception and production suggest e.g. phonological loop effects analogous to those obtained for speech processing. Neuroimaging studies will have to address this potential communality.     

Language Organization and Reorganization in Epilepsy

The vast majority of healthy individuals are left hemisphere dominant for language; however, individuals with left hemisphere epilepsy have a higher likelihood of atypical language organization. The cerebral organization of language in epilepsy has been studied with invasive procedures such as Wada testing and electrical cortical stimulation mapping (ESM), and more recently, with noninvasive neuroimaging techniques such as functional magnetic resonance imaging (fMRI). Investigators have used these techniques to explore the influence of unique clinical features inherent in epilepsy that might contribute to the reorganization of language, such as location of seizure onset, age of seizure onset, and extent of interictal epileptiform activity. In this paper, we review the contribution of these and other clinical variables to the lateralization and localization of language in epilepsy, and how these patient-related variables affect the results from these three different, yet complementary methodologies. Unlike the abrupt language changes that occur following acute brain injury with disruption of established language circuits, converging evidence suggests that the chronic nature of epileptic activity can result in a developmental shift of language from the left to the right hemisphere or re-routing of language pathways from traditional to non-traditional areas within the dominant left hemisphere. Clinical variables have been shown to contribute to cerebral language reorganization in the setting of chronic seizure disorders, yet such factors have not been reliable predictors of altered language networks in individual patients, underscoring the need for language lateralization and localization procedures when definitive identification of language cortex is necessary for clinical care.     

Expression and interpretation of emotions in multilingual psychotherapy: A literature review

This review aimed at presenting the findings of 19 original studies that were published in the period from 2000 to 2022 in order to outline the current state of the art in the field of emotion communication (i.e., expressing and interpreting emotions) in multilingual psychotherapy. This analysis involves in particular the studies that investigate multilingual phenomena (e.g., code-switching and language-mixing) that occur during psychotherapeutic sessions when client and therapist can speak more than one language, as well as the articles that research emotion communication in this multilingual setting. With this in mind, the articles selected for this review are divided into two main categories: linguistic phenomena in multilingual psychotherapy and emotion communication in multilingual psychotherapy. Results of the studies in the current analysis reveal that code-switching remains one of the main linguistic phenomena that arises in the area of multilingual psychotherapy. Switching languages in therapy tends to be considered as beneficial for both client and therapist. Besides, findings suggest a connection between speaking L1/LX and one's identity (e.g., feeling different depending on the language). Additionally, studies that investigate emotion communication in multilingual psychotherapy show that an individual's first language (L1) is predominantly viewed as more emotionally charged than their language(s) learned later in life (LX). However, some studies also demonstrate that the relationship between L1 and LX is more fluid and context-dependent than it has traditionally been regarded. Propositions are given for future research in the field of emotion communication in multilingual psychotherapy.     

Some comments on Lehrer semantics

Lehrer Semantics, as it was devised by Adrienne and Keith Lehrer, is imbedded in a comprehensive web of thought and observations of language use and development, communication, and social interaction, all these as empirical phenomena. Rather than for a theory, I take it for a ??model?? of the kind which gives us guidance in how to organize linguistic and language-related phenomena. My comments on it are restricted to three aspects: In 2 I deal with the question of how Lehrerian sense can be empirically distinguished from Lehrerian reference as a precondition for the claim that sense relationships are in general more stable than reference relations. It seems that this very claim must already be presupposed for doing the respective empirical investigation. But in 3, I argue for the option to interpret the Lehrers?? concept of sense resp. sense vectors as intension concepts, by which move one may gain a generalized concept, so-to-say ??graded analyticity??, containing Carnapian strict analyticity for language systems as the extreme case of sense vectors with maximum value. Such graded sense may also be empirically investigated in the case of normal languages. In 4, I plead for my view that what the Lehrers take for communal languages are really collections of family-resembling idiolects of individual speakers and hypotheses of individual speakers about the idiolects of their fellow speakers. This move should free us from the fiction of, and sterile discussions about, the ??true?? meanings of words, but nevertheless keep normal language communication possible. As a concluding remark I propose in 5 to have both: normal languages from an empirical point of view, and codified languages from a logical reconstructionist one.     

The bilingual brain: cerebral representation of languages.

The present article deals with theoretical and experimental aspects of language representation in the multilingual brain. Two general approaches were adopted in the study of the bilingual brain. The study of bilingual aphasics allows us to describe dissociations and double dissociations between the different subcomponents of the various languages. Furthermore, symptoms peculiar to bilingual aphasia were reported (pathological mixing and switching and translations disorders) which allowed the correlation of some abilities specific to bilinguals with particular neurofunctional systems. Another approach to the study of the bilingual brain is of the experimental type, such as electrophysiological investigations (electrocorticostimulation during brain surgery and event-related potentials) and functional neuroanatomy studies (positron emission tomography and functional magnetic resonance imaging). Functional neuroanatomy studies investigated the brain representation of languages when processing lexical and syntactic stimuli and short stories. Neurophysiologic and neuroimaging studies evidenced a similar cerebral representation of L1 and L2 lexicons both in early and late bilinguals. The representation of grammatical aspects of languages seems to be different between the two languages if L2 is acquired after the age of 7, with automatic processes and correctness being lower than those of the native language. These results are in line with a greater representation of the two lexicons in the declarative memory systems, whereas morphosyntactic aspects may be organized in different systems according to the acquisition vs learning modality.     

Inhibition of non-target languages in multilingual word production: Evidence from Uighur–Chinese–English trilinguals

The present study examined the hypothesis whether non-target languages are inhibited during multilingual language production by examining the n-2 language repetition cost. In two experiments, Uighur–Chinese–English trilinguals named Arabic digits in one of their three languages according to a visually presented cue. Significant n-2 repetition costs were obtained in both experiments, which indicate that inhibition exists during multilingual word production. In addition, in Experiment 1, it was also found that the n-2 repetition cost was reduced when cues were highly compatible with the task, which means non-target languages are less inhibited. In Experiment 2, the n-2 repetition cost was increased at a shorter CSI. Taken together, these results indicate that inhibition of non-target languages occurs during multilingual language production, and that efficiency of establishing the target language task schema has an effect on the inhibitory control process.     

Bilingualism and brain functional asymmetry

The task of the neural organization of the native language, acquired by a direct method and of another language, studied at school, performed correspondingly by the left and the right hemispheres, was studied in the bilingual patient after unilateral electroconvulsive therapy used in psychiatry. It was established that in such a bilingual type the right hemisphere is concerned with the formation of deep semantic structures of the native language while the left hemisphere is responsible for the formation of second language deep structures and of surface structures of both languages. The effect of language learning method on cerebral organization of bilingualism is postulated.     

Parental language mixing in bilingual families

An important question about early bilingualism that concerns both parents and researchers is the degree to which one language may interfere with another. This question rests on an implicit assumption that learning more than one language must always produce confusion and/or interference between (or among) the languages. Although many naturalistic studies have addressed this issue, no firm answers are yet available from the conflicting results obtained. Several factors appear to be responsible for the contradictory evidence, including the small numbers of subjects in each study, the large number of different language combinations of varying similarity that have been examined, and the variety of linguistic input situations (e.g., sequential bilingualism, language separation between home and school, parent/language separation), that have been observed. There is a consensus that children's language mixing can be eliminated if parents adhere strictly to the principle of one parent/one language enunciated by Grammont (Ronjat, 1913). However, this claim has not been directly examined. The primary goal of the present study is to characterize the linguistic input available to a child growing up with two languages. Analyses of the data show that a large proportion of parents, even those firmly committed to maintaining a strict separation of language by parent, model linguistically mixed utterances for their children. This finding suggests that children's early language mixing does not reflect interlinguistic confusion. Rather, it suggests that the child is formulating hypotheses about language based on the data available, i.e., that using the language of both father and mother in a single utterance is acceptable.     

Language lateralization in bilinguals: enough already!

All clinical evidence points to the fact that both languages of bilinguals are subserved by the left hemisphere in the same proportion as in unilinguals. Half of the experimental studies have reported no significant difference in lateralization between unilinguals and bilinguals. Those studies that have reported a difference contradict each other with respect to the bilingual subpopulations that are alleged to exhibit differential laterality. In the face of the lack of demonstrated validity of dichotic, tachistoscopic, and time-sharing paradigms in reflecting laterality of language functions in bilinguals, it may be time for neuropsychologists to move on to more productive research.     

Comparing language and religion in normative arguments about linguistic justice

Many of the most influential theorists of linguistic justice make arguments on the basis of comparisons between language and religion. They claim either that (1) language, by contrast with religion, cannot be separated from the state or that (2) unequal official linguistic recognition, just like unequal official religious recognition, is morally problematic. This article argues that careful attention to debates about liberalism and the place of religion in public life invites us to question the two above-mentioned liberal assumptions about religion underlying many arguments concerning linguistic justice based on (dis)analogies between language and religion. The hope is that such critical scrutiny is likely to shed some light on normative questions of linguistic justice, more precisely on questions about the legitimacy of granting more recognition to certain languages, usually those of national native groups (as opposed to groups resulting from more or less recent immigration).     

In search of the language switch: An fMRI study of picture naming in Spanish-English bilinguals

For many years, researchers investigating the brain bases of bilingualism have concentrated on two basic questions. The first concerns the nature of language representation. That is, are a bilinguals' two languages represented in distinct or overlapping areas of the brain. The second basic question in the neuropsychology of bilingualism concerns the neural correlates of language switching, that is, the areas that are active when bilinguals switch from one language to the other. Performance between single-language and dual-language picture naming was compared in a group of six Spanish-English bilinguals using behavioral measures and functional magnetic resonance imaging. Participants showed slower reaction times and increased activation in the dorsolateral prefrontal cortex in the mixed language condition relative to single language condition. There was no evidence that each language was represented in different areas of the brain. Results are consistent with the view that language switching is a part of a general executive attentional system and that languages are represented in overlapping areas of the brain in early bilinguals.     

Becoming literate in different languages: similar problems, different solutions

The teaching of reading in different languages should be informed by an effective evidence base. Although most children will eventually become competent, indeed skilled, readers of their languages, the pre-reading (e.g. phonological awareness) and language skills that they bring to school may differ in systematic ways for different language environments. A thorough understanding of potential differences is required if literacy teaching is to be optimized in different languages. Here we propose a theoretical framework based on a psycholinguistic grain size approach to guide the collection of evidence in different countries. We argue that the development of reading depends on children's phonological awareness in all languages studied to date. However, we propose that because languages vary in the consistency with which phonology is represented in orthography, there are developmental differences in the grain size of lexical representations, and accompanying differences in developmental reading strategies across orthographies.     

Functional Lateralization of the Perception of Norwegian Word Tones - Evidence from a Dichotic Listening Experiment

The present paper addresses the question of the functional lateralization of the ability to perceive the tonal distinctions in tone languages. Dichotic listening experiments and investigations of the brain-damaged population have indicated that the left hemisphere is more active than the right in the perception of tone in East Asian tone languages like Mandarin Chinese and Thai. Two dichotic listening experiments involving speakers of Norwegian, a language with an opposition of two tones, have demonstrated a right-ear superiority in the perception of the tonal distinction, indicating left-hemisphere lateralization of the ability to perceive tonal distinctions in Norwegian as well as in the East Asian tone languages that have been previously investigated.