Neural specificity for semantic and syntactic processing in Spanish-English bilingual children.

Brain development for language processing is associated with neural specialization of left perisylvian pathways, but this has not been investigated in young bilinguals. We examined specificity for syntax and semantics in early exposed Spanish-English speaking children (N = 65, ages 7-11) using an auditory sentence judgement task in English, their dominant language of use. During functional near infrared spectroscopy (fNIRS), the morphosyntax task elicited activation in left inferior frontal gyrus (IFG) and the semantic task elicited activation in left posterior middle temporal gyrus (MTG). Task comparisons revealed specialization in left superior temporal (STG) for morphosyntax and left MTG and angular gyrus for semantics. Although skills in neither language were uniquely related to specialization, skills in both languages were related to engagement of the left MTG for semantics and left IFG for syntax. These results are consistent with models suggesting a positive cross-linguistic interaction in those with higher language proficiency.

Brain bases of English morphological processing: A comparison between Chinese-English, Spanish-English bilingual, and English monolingual children.

How do early bilingual experiences influence children's neural architecture for word processing? Dual language acquisition can yield common influences that may be shared across different bilingual groups, as well as language-specific influences stemming from a given language pairing. To investigate these effects, we examined bilingual English speakers of Chinese or Spanish, and English monolinguals, all raised in the US (N = 152, ages 5-10). Children completed an English morphological word processing task during fNIRS neuroimaging. The findings revealed both language-specific and shared bilingual effects. The language-specific effects were that Chinese and Spanish bilinguals showed principled differences in their neural organization for English lexical morphology. The common bilingual effects shared by the two groups were that in both bilingual groups, increased home language proficiency was associated with stronger left superior temporal gyrus (STG) activation when processing the English word structures that are most dissimilar from the home language. The findings inform theories of language and brain development during the key periods of neural reorganization for learning to read by illuminating experience-based plasticity in linguistically diverse learners.

Morphological and phonological processing in English monolingual, Chinese-English bilingual, and Spanish-English bilingual children: An fNIRS neuroimaging dataset.

This article documents a functional Near-Infrared Spectroscopy (fNIRS) neuroimaging dataset deposited in Deep Blue Data. The dataset included neuroimaging and behavioral data from N = 343 children aged 5-11 with a diverse linguistic background, including children who are English monolingual, Chinese-English, and Spanish-English bilingual. Children completed phonological and morphological awareness tasks in each of their languages during fNIRS neuroimaging. They also completed a wide range of language and reading tasks. Parents filled in questionnaires to report children's demographic information as well as their home language and literacy backgrounds. The dataset is valuable for researchers in the field of developmental cognitive neuroscience to further investigate questions such as the effects of bilingualism on children's neural basis for literacy development.

Person-specific connectivity mapping uncovers differences of bilingual language experience on brain bases of attention in children.

Bilingualism influences children's cognition, yet bilinguals vary greatly in their dual-language experiences. To uncover sources of variation in bilingual and monolingual brain function, the present study used standard analysis and innovative person-specific connectivity models combined with a data-driven grouping algorithm. Children (ages 7-9; N = 52) completed a visuo-spatial attention task while undergoing functional near-infrared spectroscopy neuroimaging. Both bilingual and monolingual groups performed similarly, and engaged bilateral frontal and parietal regions. However, bilinguals showed greater brain activity than monolinguals in left frontal and parietal regions. Connectivity models revealed two empirically-derived subgroups. One subgroup was composed of monolinguals and bilinguals who were more English dominant, and showed left frontal-parietal connections. The other was composed of bilinguals who were balanced in their dual-language abilities and showed left frontal lobe connections. The findings inform how individual variation in early language experiences influences children's emerging cortical networks for executive function, and reveal efficacy of data-driven approaches.

Cross-linguistic differences in the associations between morphological awareness and reading in Spanish and English in young simultaneous bilinguals.

This study aimed to clarify the relations between morphological awareness and literacy skills in Spanish and English in young simultaneous bilingual learners. Guided by theoretical perspectives on the associations between morphological awareness and word- versus sentence-level literacy skills, and their transfer between bilinguals' two languages, we asked bilingual children (N = 90; M = 8.07 years old) to complete dual-language literacy assessments. First, we observed cross-linguistic differences in the associations between morphology and reading. In English, morphological awareness was directly related to word reading and reading comprehension, whereas in Spanish, the association with reading comprehension was fully mediated by vocabulary and single word reading. Second, we observed cross-linguistic associations from English word reading to Spanish reading comprehension, and from Spanish reading comprehension to English reading comprehension. Our findings inform bilingual literacy theory by revealing both cross-linguistic differences and bidirectional associations between literacy skills across typologically-distinct orthographies. In particular, children's word-level skills transferred from the language of schooling (English) into their heritage language (Spanish), and their broader reading comprehension skills transferred from the heritage language to support English. Taken together, these findings support the value of bilingual heritage language maintenance for reading achievement in children's dominant language of literacy instruction.

Bilingual exposure enhances left IFG specialization for language in children.

Language acquisition is characterized by progressive use of inflectional morphology marking verb tense and agreement. Linguistic milestones are also linked to left-brain lateralization for language specialization. We used neuroimaging (fNIRS) to investigate how bilingual exposure influences children's cortical organization for processing morpho-syntax. In Study 1, monolinguals and bilinguals (n=39) completed a grammaticality judgment task that included English sentences with violations in earlier- (verb agreement) and later-acquired (verb tense/agreement) structures. Groups showed similar performance and greater activation in left inferior frontal region (IFG) for later- than earlier-acquired conditions. Bilinguals showed stronger and more restricted left IFG activation. In Study 2, bilinguals completed a comparable Spanish task revealing patterns of left IFG activation similar to English. Taken together, the findings suggest that bilinguals with linguistic competence at parity with monolingual counterparts have a higher degree of cortical specialization for language, likely a result of enriched linguistic experiences.

Bilingual effects on lexical selection: A neurodevelopmental perspective.

When a listener hears a word, multiple lexical items may come to mind; for instance, /kæn/ may activate concepts with similar phonological onsets such as candy and candle. Acquisition of two lexicons may increase such linguistic competition. Using functional Near-Infrared Spectroscopy neuroimaging, we investigate whether bilingualism impacts word processing in the child's brain. Bilingual and monolingual children (N = 52; ages 7-10) completed a lexical selection task in English, where participants adjudicated phonological competitors (e.g., car/cat vs. car/pen). Children were less accurate and responded more slowly during competing than non-competing items. In doing so, children engaged top-down fronto-parietal regions associated with cognitive control. In comparison to bilinguals, monolinguals showed greater activity in left frontal regions, a difference possibly due to bilinguals' adaptation for dual-lexicons. These differences provide insight to theories aiming to explain the role of experience on children's emerging neural networks for lexical selection and language processing.

The effects of Spanish heritage language literacy on English reading for Spanish-English bilingual children in the US.

Models of monolingual literacy propose that reading acquisition builds upon children's semantic, phonological, and orthographic knowledge. The relationships between these components vary cross-linguistically, yet it is generally unknown how these differences impact bilingual children's literacy. A comparison between Spanish-English bilingual and English monolingual children (ages 6-13, N=70) from the U.S. revealed that bilinguals had stronger associations between phonological and orthographic representations than monolinguals during English reading. While vocabulary was the strongest predictor of English word reading for both groups, phonology and morpho-syntax were the best predictors of Spanish reading for bilinguals. This comparison reveals distinct developmental processes across learners and languages, and suggests that early and systematic biliteracy exposure at home and through afterschool programs can influence children's sound-to-print associations even in the context of language-specific (monolingual) reading instruction. These findings have important implications for bilingual education as well as theories that aim to explain how learning to read across languages has a positive impact on the acquisition of literacy.

Bilingualism alters children's frontal lobe functioning for attentional control.

Bilingualism is a typical linguistic experience, yet relatively little is known about its impact on children's cognitive and brain development. Theories of bilingualism suggest that early dual-language acquisition can improve children's cognitive abilities, specifically those relying on frontal lobe functioning. While behavioral findings present much conflicting evidence, little is known about its effects on children's frontal lobe development. Using functional near-infrared spectroscopy (fNIRS), the findings suggest that Spanish-English bilingual children (n = 13, ages 7-13) had greater activation in left prefrontal cortex during a non-verbal attentional control task relative to age-matched English monolinguals. In contrast, monolinguals (n = 14) showed greater right prefrontal activation than bilinguals. The present findings suggest that early bilingualism yields significant changes to the functional organization of children's prefrontal cortex for attentional control and carry implications for understanding how early life experiences impact cognition and brain development.