Effects of dense code-switching on executive control

Bilingualism is reported to re-structure executive control networks, but it remains unknown which aspects of the bilingual experience cause this modulation. This study explores the impact of three code-switching types on executive functions: (1) alternation, (2) insertion, and (3) dense code-switching or congruent lexicalisation. Current models hypothesise that different code-switching types challenge different aspects of the executive system because they vary in the extent and scope of language separation. Two groups of German-English bilinguals differing in dense code-switching frequency participated in a flanker task under conditions varying in degree of trial-mixing and resulting demands to conflict-monitoring. Bilinguals engaging in more dense code-switching showed inhibitory advantages in the condition requiring most conflict-monitoring. Moreover, dense code-switching frequency correlated positively with monitoring skills. This suggests that dense code-switching is a key experience shaping bilinguals’ executive functioning and highlights the importance of controlling for participants’ code-switching habits in bilingualism research

Predicting executive functions in bilinguals using ecologically valid measures of code-switching behaviour

The study of bilingualism has charted a dramatically new, important, and exciting course in the 21st century, benefiting from the integration in cognitive science of theoretical linguistics, psycholinguistics, and cognitive psychology (especially work on the higher-level cognitive processes often called executive function or executive control). Current research, as exemplified in this book, advances the study of the effects of bilingualism on executive function by identifying many different ways of being bilingual, exploring the multiple facets of executive function, and developing and analyzing tasks that measure executive function. The papers in this volume (21 chapters), by leading researchers in bilingualism and cognition, investigate the mechanisms underlying the effects (or lack thereof) of bilingualism on cognition in children, adults, and the elderly. They take us beyond the standard, classical, black-and-white approach to the interplay between bilingualism and cognition by presenting new methods, new findings, and new interpretations

Experimentally Induced Language Modes and Regular Code-Switching Habits Boost Bilinguals’ Executive Performance: Evidence From a Within-Subject Paradigm

Bilingualism may modulate executive functions (EFs), but the mechanisms underlying this phenomenon are poorly understood. In this study, we investigated two potential sources of variability in bilinguals’ EF performance: (1) interactional contexts and code-switching, and (2) dominance profiles. Previous research on code-switching often relied on self-reports of regular code-switching habits. In this study, we investigated the effects of experimentally induced language modes (single language versus code-switching modes) on bilinguals’ EF performance. Crucially, in the bilingual conditions, we differentiated between different types of intra-sentential code-switching (Insertion, Alternation, and Dense code-switching). Moreover, we investigated the interaction of the effects of temporary language modes with bilinguals’ sociolinguistic code-switching habits. All our participants were L1-dominant German–English bilinguals (N = 29) immersed in an L2 context. We assessed the effects of dominance by correlating individual bilinguals’ L1-dominance with their EF performance. In addition, we investigated whether language modes activate different EF patterns in bilinguals, as opposed to monolinguals, i.e., individuals who have no additional language to suppress. Based on models of bilingual language processing, we predicted our bilinguals to display the best EF performance in L2 single language contexts, as these require them to activate inhibitory schemata to suppress their dominant L1. Indeed, bilinguals performed better in the single language than in the code-switching conditions. The results also suggested that bilinguals activated more inhibitory control compared to monolinguals, supporting the notion that bilingual processing involves inhibition. The task conditions inducing different code-switching modes differed only in terms of the predictors explaining EF performance in the regression. We observed negative correlations between the frequency of engaging in a given type of code-switching and performance in language modes inducing non-corresponding control modes. The results suggested that Dense code-switching draws upon proactive control modes that differ from the reactive control involved in Alternation. Importantly, bilinguals’ dominance profiles played a crucial role in explaining EF performance. The more balanced individuals in our overall L1-dominant sample displayed better EF performance in the bilingual conditions, suggesting that more balanced bilingualism trains the control modes involved in code-switching. This highlights the importance of assessing bilinguals’ sociolinguistic profiles in bilingualism research

On well-posedness, stability, and bifurcation for the axisymmetric surface diffusion flow

In this article, we study the axisymmetric surface diffusion flow (ASD), a fourth-order geometric evolution law. In particular, we prove that ASD generates a real analytic semiflow in the space of (2 + \alpha)-little-H\"older regular surfaces of revolution embedded in R^3 and satisfying periodic boundary conditions. We also give conditions for global existence of solutions and prove that solutions are real analytic in time and space. Further, we investigate the geometric properties of solutions to ASD. Utilizing a connection to axisymmetric surfaces with constant mean curvature, we characterize the equilibria of ASD. Then, focusing on the family of cylinders, we establish results regarding stability, instability and bifurcation behavior, with the radius acting as a bifurcation parameter for the problem.Comment: 37 pages, 6 figures, To Appear in SIAM J. Math. Ana

Linguistic diversity, multilingualism, and cognitive skills: A study of disadvantaged children in India

Multilingualism and linguistic diversity are the norm in India. Although studies have shown a relation between bilingualism and cognitive gains, linguistic diversity has so far been ignored as a potential factor affecting cognitive skills. This study aims to fill this gap by examining how cognitive skills—as measured by the n-back and Raven’s Colored Progressive Matrices tasks—are affected by multilingualism and/or sociolinguistic diversity in a large cohort of socioeconomically disadvantaged primary school children in two urban sites of India: Delhi and Hyderabad. We present a questionnaire estimating sociolinguistic diversity and show that this measure assesses a distinct construct, as compared to a child’s multilingualism. Children were classified as growing up monolingually or bilingually, depending on whether they grew up with one or more languages in the home. Regarding cognitive performance, bilinguals were found to outperform monolinguals on the n-back task, as well as on the Raven’s task. In addition, a socially and linguistically diverse environment seems to enhance cognitive performance for children who are not multilingual themselves. Finally, several contextual factors such as city were found to influence cognitive performance. Overall, this shows that cognitive tasks are subject to contextual effects and that bilingualism and linguistic diversity can enhance cognitive performance of children in disadvantaged contexts.</jats:p

The potential of sentence imitation tasks for assessment of language abilities in sequential bilingual children

Sentence repetition tasks are increasingly recognised as a useful clinical tool for diagnosing language impairment in children. They are quick to administer, can be carefully targeted to elicit specific sentence structures, and are particularly informative about children’s lexical and morphosyntactic knowledge. This chapter exlores the theoretical potential of sentence repetition for assessment of sequential bilingual children, and presents three studies comparing performance of sequential bilingual children with monolingual children’s performance on standardised sentence repetition tests in Hebrew (children with L1 Russian, age 5-7 years, and L1 English, age 4½-6½ years), German (children with L1 Russian, age 4-7 years) and English (children with L1 Turkish, age 6-9 years). Results differed across studies: distribution of children in the Hebrew studies was in line with monolingual norms, while the majority of children in the English-Turkish study scored in a range that would be deemed impaired for monolingual children, and performance in the German-Russian study fell between these extremes. Analyses of performance within studies revealed similar discrepancies in effects of children’s exposure to L2, with significant effects of Age of Onset in the Hebrew-Russian and Hebrew-English groups and some indication of Length of Exposure effects, but no effects of either factor in the English-Turkish group. Multiple differences between these studies preclude direct inferences about the reasons for these different results: studies differed in content, methods and scoring of sentence repetition tests, and in ages, languages, language exposure, and socioeconomic status of participants. It is possible that socioeconomic differences are associated with differences in language experience that are equally or more important than onset and length of exposure. Collectively, these studies demonstrate that sentence repetition provides a measure of children’s proficiency in their L2, but that the use of sentence repetition in clinical assessment requires caution unless norms are available for the child’s bilingual community. As a next step, it is proposed that sentence repetition tests using early-acquired vocabulary and targeting aspects of sentence structure known to be difficult for monolingual children with language impairments should be developed in different target languages. This will allow us to explore further the factors that influence attainment of basic morphosyntax in sequential bilingual children, and the point at which sentence repetition, as a measure of morphosyntax, can help to identify children requiring clinical intervention

Pressure injury progression and factors associated with different end-points in a home palliative care setting : a retrospective chart review study

CONTEXT: Patients with advanced illnesses show the highest prevalence for pressure injuries. In the palliative care setting, the ultimate goal is injury healing, but equally important is wound maintenance, wound palliation (wound-related pain and symptom management), and primary and secondary wound prevention. OBJECTIVES: To describe the course of healing for pressure injuries in a home palliative care setting according to different end-points, and to explore patient and caregiver characteristics and specific care activities associated with their achievement. METHODS: Four-year retrospective chart review of 669 patients cared for in a home palliative care service, of those 124 patients (18.5%) had at least one pressure injury with a survival rate less than or equal to six months. RESULTS: The proportion of healed pressure injuries was 24.4%. Of the injuries not healed, 34.0% were in a maintenance phase, whereas 63.6% were in a process of deterioration. Body mass index (P = 0.0014), artificial nutrition (P = 0.002), and age &lt;70 years (P = 0.022) emerged as predictive factors of pressure injury complete healing. Artificial nutrition, age, male caregiver (P = 0.034), and spouse (P = 0.036) were factors significantly associated with a more rapid pressure injury healing. Continuous deep sedation was a predictive factor for pressure injury deterioration and significantly associated with a more rapid worsening. CONCLUSION: Pressure injury healing is a realistic aim in home palliative care, particularly for injuries not exceeding Stage II occurring at least two weeks before death. When assessing pressure injuries, our results highlight the need to also pay attention to artificial nutrition, continuous deep sedation, and the caregiver's role and gender

Effects of mother tongue education and multilingualism on reading skills in the regional language and English in India

In a highly multilingual country like India, challenges and opportunities arise in education and language policy. Although multilingualism is often associated with developmental advantages, Indian primary school children generally show low learning outcomes, specifically on literacy. Here we examine the influence of mother tongue education and multilingualism on the reading skills and reading comprehension of 1272 Indian primary school children from low SES homes. The children performed the ASER literacy task in both the regional, majority language and in English, which was followed by newly developed reading comprehension questions. The results show that minority language speakers from monolingual households—who do not receive mother tongue education—underperform compared to majority language speakers when reading in the majority language. When reading in English, growing up in a multilingual household improves children\u27s performance. Finally, in sites which have a larger proportion of mother tongue-educated children, children perform better in literacy in the regional language and worse in English. Overall, these results provide insight into the influence of mother tongue education and multilingualism on reading abilities and show that more support is needed for minority language speakers to develop literacy in the majority language, and for all children to develop literacy in English