Bilingual effects on deployment of the attention system in linguistically and culturally homogeneous children and adults

Robustness of the cognitive gains in 7-month-old bilingual infants: A close multi-center replication of Kovács and Mehler (2009)

We present an exact replication of Experiment 2 from Kovács and Mehler's 2009 study, which showed that 7-month-old infants who are raised bilingually exhibit a cognitive advantage. In the experiment, a sound cue, following an AAB or ABB pattern, predicted the appearance of a visual stimulus on the screen. The stimulus appeared on one side of the screen for nine trials and then switched to the other side. In the original experiment, both mono- and bilingual infants anticipated where the visual stimulus would appear during pre-switch trials. However, during post-switch trials, only bilingual children anticipated that the stimulus would appear on the other side of the screen. The authors took this as evidence of a cognitive advantage. Using the exact same materials in combination with novel analysis techniques (Bayesian analyses, mixed effects modeling and cluster based permutation analyses), we assessed the robustness of these findings in four babylabs (N = 98). Our results did not replicate the original findings: although anticipatory looks increased slightly during post-switch trials for both groups, bilingual infants were not better switchers than monolingual infants. After the original experiment, we presented additional trials to examine whether infants associated sound patterns with cued locations, for which we did not find any evidence either. The results highlight the importance of multicenter replications and more fine-grained statistical analyses to better understand child development. HIGHLIGHTS: We carried out an exact replication across four baby labs of the high-impact study by Kovács and Mehler (2009). We did not replicate the findings of the original study, calling into question the robustness of the claim that bilingual infants have enhanced cognitive abilities. After the original experiment, we presented additional trials to examine whether infants correctly associated sound patterns with cued locations, for which we did not find any evidence. The use of novel analysis techniques (Bayesian analyses, mixed effects modeling and cluster based permutation analyses) allowed us to draw better-informed conclusions.

Is there a cognitive advantage in inhibition and switching for bilingual children? A systematic review

Several studies have pointed to beneficial effects of bilingualism on executive functioning. However, observations of these beneficial effects have at times proven difficult to reproduce. Moreover, findings of studies on cognitive effects of bilingualism have been contested altogether. These contradictory outcomes leave the research field of bilingualism at unease. In the present review article, we aim to give a systematic overview of previous research on bilingual advantages in inhibition and switching in children up to the age of 12. Particular attention is paid to the experimental tasks that have been applied and the persistence of possible effects throughout critical and post-critical periods for cognitive development in children. In doing so, the review gives an insight in both the validity and robustness of possible domain-general cognitive effects of bilingualism in children. Terminological issues are also discussed.

Monolingual and bilingual children's performance on arithmetic fluency varies by language fluency

Research has demonstrated that learning two or more languages during development (i.e., becoming bilingual) shapes children's cognition in myriad ways. However, because such studies have largely been conducted using laboratory experiments, it is unclear how bilingualism may modulate more naturalistic cognitive skills such as arithmetic fluency. Moreover, how the relationship between speaking two (or more) languages and arithmetic varies with language fluency-specifically, the degree of bilingualism-has been understudied. Therefore, this study examined third- to fifth-grade monolingual (n = 70) and bilingual (n = 51) children's performance on an arithmetic fluency task. Monolinguals' and bilinguals' performance on the arithmetic fluency task did not differ. However, individual differences in the relation between children's arithmetic fluency and their language fluency were found, suggesting that bilingual children's skill in their nondominant language was associated with arithmetic fluency. These findings point to the importance of examining individual differences in language fluency among bilinguals to understand how bilingualism may shape cognitive skills.

Sensitivity to visual cues within motion events in monolingual and bilingual infants

It is well known that infants undergo developmental change in how they respond to language-relevant visual contrasts. For example, when viewing motion events, infants' sensitivities to background information ("ground-path cues," e.g., whether a background is flat and continuous or bounded) change with age. Prior studies with English and Japanese monolingual infants have demonstrated that 14-month-old infants discriminate between motion events that take place against different ground-paths (e.g., an unbounded field vs a bounded street). By 19 months of age, this sensitivity becomes more selective in monolingual infants; only learners of languages that lexically contrast these categories, such as Japanese, discriminate between such events. In this study, we investigated this progression in bilingual infants. We first replicated past reports of an age-related decline in ground-path sensitivity from 14 to 19 months in English monolingual infants living in a multilingual society. English-Mandarin bilingual infants living in that same society were then tested on discrimination of ground-path cues at 14, 19, and 24 months. Although neither the English nor Mandarin language differentiates motion events based on ground-path cues, bilingual infants demonstrated protracted sensitivity to these cues. Infants exhibited a lack of discrimination at 14 months, followed by discrimination at 19 months and a subsequent decline in discrimination at 24 months. In addition, bilingual infants demonstrated more fine-grained sensitivities to subtle ground cues not observed in monolingual infants.

How does bilingualism modify cognitive function? Attention to the mechanism

It has been claimed that bilingual experience leads to an enhancement of cognitive control across the lifespan, a claim that has been investigated by comparing monolingual and bilingual groups performing standard executive function (EF) tasks. The results of these studies have been inconsistent, however, leading to controversy over the essential assumptions underlying the research program, namely, whether bilingualism produces cognitive change. We argue that the source of the inconsistency is not in the evidence but rather in the framework that has typically been used to motivate the research and interpret the results. We examine the componential view of EF with its central role for inhibition and argue that it provides a poor fit to both bilingual experience and the results of these studies. As an alternative, we propose a more holistic account based on attentional control that overrides the processes in the componential model of EF and applies to a wider range of tasks. The key element in our account is that behavioral differences between monolingual and bilingual individuals reflect differences in the efficiency and deployment of attentional control between the two language groups. In support of this point we show how attentional control provides a more satisfactory account for a range of findings that cannot reasonably be attributed to inhibition. We also suggest that group differences will emerge only when the attentional demands of a task exceed the control abilities of one of the groups, regardless of the EF components involved. We then review literature from across the lifespan to evaluate the extent to which this account is consistent with existing evidence, and conclude with some suggestions on how the field may be advanced by new lines of empirical enquiry.

Predicting multilingual effects on executive function and individual connectomes in children: An ABCD study

While there is a substantial amount of work studying multilingualism's effect on cognitive functions, little is known about how the multilingual experience modulates the brain as a whole. In this study, we analyzed data of over 1,000 children from the Adolescent Brain Cognitive Development (ABCD) Study to examine whether monolinguals and multilinguals differ in executive function, functional brain connectivity, and brain-behavior associations. We observed significantly better performance from multilingual children than monolinguals in working-memory tasks. In one finding, we were able to classify multilinguals from monolinguals using only their whole-brain functional connectome at rest and during an emotional n-back task. Compared to monolinguals, the multilingual group had different functional connectivity mainly in the occipital lobe and subcortical areas during the emotional n-back task and in the occipital lobe and prefrontal cortex at rest. In contrast, we did not find any differences in behavioral performance and functional connectivity when performing a stop-signal task. As a second finding, we investigated the degree to which behavior is reflected in the brain by implementing a connectome-based behavior prediction approach. The multilingual group showed a significant correlation between observed and connectome-predicted individual working-memory performance scores, while the monolingual group did not show any correlations. Overall, our observations suggest that multilingualism enhances executive function and reliably modulates the corresponding brain functional connectome, distinguishing multilinguals from monolinguals even at the developmental stage.

Disentangling language status and country-of-origin explanations of the bilingual advantage in preschoolers

Bilingual preschoolers from East Asia outperform monolingual preschoolers from North America or Europe in executive functioning tasks, which has been interpreted as evidence of a bilingual advantage in executive functioning. This study tested whether these differences actually reflect country-of-origin effects given that East Asian preschoolers frequently outperform North American or European children in executive functioning tasks. Consistent with previous findings, Korean-English bilingual preschoolers made fewer errors in an age-appropriate executive functioning task than did English monolingual children in Canada. However, Korean-English bilingual preschoolers performed comparably to Korean monolingual preschoolers in Korea. Differences between Korean and Canadian children's executive functioning were not attributable to differences in parental cultural values or attitudes. The current findings suggest that differences between East Asian bilingual and North American monolingual preschoolers' executive functioning is related to differences in country of origin rather than language status.

The Impact of Bilingualism on Executive Functions in Children and Adolescents: A Systematic Review Based on the PRISMA Method

Approximately half of the world's population is bilingual or multilingual. The bilingual advantage theory claims that the constant need to control both known languages, that are always active in the brain, to use the one suitable for each specific context improves cognitive functions and specifically executive functions. However, some authors do not agree on the bilingual effect, given the controversial results of studies on this topic. This systematic review aims to summarize the results of studies on the relationship between bilingualism and executive functions. The review was conducted according to PRISMA-statement through searches in the scientific database PsychINFO, PsycARTICLES, MEDLINE, and PUBMED. Studies included in this review had at least one bilingual and monolingual group, participants aged between 5 and 17 years, and at least one executive function measure. Studies on second language learners, multilingual people, and the clinical population were excluded. Fifty-three studies were included in the systematic review. Evidence supporting the bilingual effect seems to appear when assessing inhibition and cognitive flexibility, but to disappear when working memory is considered. The inconsistent results of the studies do not allow drawing definite conclusions on the bilingual effect. Further studies are needed; they should consider the role of some modulators (e.g., language history and context, methodological differences) on the observed results.

Meta-Analysis Reveals a Bilingual Advantage That Is Dependent on Task and Age

Debate continues on whether a bilingual advantage exists with respect to executive functioning. This report synthesized the results of 170 studies to test whether the bilingual advantage is dependent on the task used to assess executive functioning and the age of the participants. The results of the meta-analyses indicated that the bilingual advantage was both task- and age-specific. Bilinguals were significantly faster than monolinguals (Hedges' g values ranged from 0.23 to 0.34), and significantly more accurate than monolinguals (Hedges' g values ranged between 0.18 and 0.49) on four out of seven tasks. Also, an effect of age was found whereby the bilingual advantage was larger for studies comprising samples aged 50-years and over (Hedges' g = 0.49), compared to those undertaken with participants aged between 18 and 29 years (Hedges' g = 0.12). The extent to which the bilingual advantage might be due to publication bias was assessed using multiple methods. These were Egger's Test of Asymmetry, Duval and Tweedie's Trim and Fill, Classic Fail-Safe N, and PET-PEESE. Publication bias was only found when using Egger's Test of Asymmetry and PET-PEESE method, but not when using the other methods. This review indicates that if bilingualism does enhance executive functioning, the effects are modulated by task and age. This may arise because using multiple languages has a highly specific effect on executive functioning which is only observable in older, relative to younger, adults. The finding that publication bias was not uniformly detected across the different methods raises questions about the impact that unpublished (or undetected) studies have on meta-analyses of this literature.

Is there a bilingual advantage on interference-control tasks? A multiverse meta-analysis of global reaction time and interference cost

A contentious issue in contemporary psycholinguistics is whether bilingualism enhances executive functions. Here, we report a meta-analysis of 80 studies (253 effect sizes) comparing performance of monolinguals and bilinguals on non-verbal interference-control tasks, while examining potential moderators of effects on two dependent variables (DVs): global reaction time (RT) and interference cost. We used a multiverse approach to determine how robust conclusions were to several dataset construction and analysis decisions. In our "preferred" analysis, using a broad definition of bilinguals and standard versions of interference-control tasks, there was a very small but significant bilingual advantage for global RT (g =.13), which became non-significant once corrected for publication bias. For interference cost, there was a very small but significant bilingual advantage (g =.11). Effects were not significantly moderated by task or participant age, but were moderated by an interaction between age of second language acquisition (AoA) and the DV. Unexpectedly, larger effect sizes for interference cost were observed for studies involving bilinguals with late as opposed to early AoA. The multiverse analysis produced results largely consistent with the preferred analysis, confirming our conclusion that evidence for a bilingual advantage on interference-control tasks is weak.

The impact of bilingualism on executive function in adolescents

AIMS AND OBJECTIVES/PURPOSE/RESEARCH QUESTIONS

In early childhood and older adulthood, bilinguals generally demonstrate better performance on executive function tasks than their monolingual counterparts, but in the young adult population, these differences are infrequently observed. However, few studies have examined these effects in the adolescent population, so the trajectory of these changes is unclear. The objective of the study was to compare performance on a modified flanker task for monolingual and bilingual adolescents, a time when the executive functions are still developing.

DESIGN/METHODOLOGY/APPROACH

The flanker task was adapted by including a rule-switching component and contained three blocks: (1) rule; (2) flanker; and (3) mixed. In the rule block, a single red or blue arrow (indicated by light grey or medium grey in Figure 1) denoted a response rule; for example, a blue arrow signaled pressing the button indicating the direction the arrow was pointing but a red arrow signaled pressing the button indicating the opposite direction. The flanker block was a standard flanker task consisting of congruent and incongruent trials. The mixed block manipulated both congruency and rule conditions.

DATA AND ANALYSIS

Mean reaction times and accuracy from 33 monolingual and 32 bilingual adolescents were analyzed using a repeated-measures analysis of variance with language group as the between-subjects variable and congruency and/or rule-type as the within-subjects variable depending on the block.

FINDINGS/CONCLUSIONS

Bilingual adolescents outperformed monolingual adolescents but only on the block that was most similar to the standard flanker task. The blocks with the rule-switching component yielded equivalent performance.

ORIGINALITY

Unlike previous studies, the current study adapted a simple executive control task to require greater attentional resources by manipulating task demands.

SIGNIFICANCE/IMPLICATIONS

Our findings add to the growing body of literature examining bilingualism and executive control in the adolescent population and fill in the gap in our understanding of the lifespan trajectory of these effects.

Bilingualism and speech recognition in silence and noise in adults

PURPOSE

To compare the ability to recognize sentences in silence and in noise in monolingual normal-hearing Brazilian Portuguese speakers, and bilingual speakers of Brazilian Portuguese and German, and bilingual speakers of Brazilian Portuguese and Italian, as well as to analyze the influence of age of second language acquisition on the performance of bilinguals.

METHODS

87 normal-hearing individuals aged between 18 and 55 years participated of this research. They were categorized into: Control Group, composed by 30 monolingual Brazilian Portuguese speakers; German Research Group, 31 simultaneous bilingual native speakers of Portuguese and speakers of German as a second language and; Italian Research Group, consisting of 26 successive bilinguals, native speakers of Portuguese and speakers of Italian as a second language. The Sentence List Test in Brazilian Portuguese was used to measure their Sentence Recognition Thresholds in Silence and Noise.

RESULTS

In silence, there were no statistically significant differences in performance when comparing the bilingual to the monolingual individuals, and when comparing the bilingual speakers among themselves. On the other hand, in noise, there was a significant difference between the bilingual groups and the monolingual one. However, there were no significant differences between the bilingual groups when their performance was compared.

CONCLUSION

Bilingualism positively influenced the development of language and listening skills, which led the bilinguals to outperform in speech recognition in the presence of noise. Also, the period of a second language acquisition did not influence bilingual performance.

Early Executive Function: The Influence of Culture and Bilingualism

Evidence suggests that cultural experiences and learning multiple languages have measurable effects on children's cognitive development (EF). However, the precise impact of how bilingualism and culture contribute to observed effects remains inconclusive. The present study aims to investigate how these factors shape the development of early EF constructs longitudinally, between monolingual and bilingual children at ages 3, 3 ½ and 4 years, with a set of EF tasks that are uniquely relevant to the effects of bilingualism and cultural practices. We hypothesize that the effects of bilingualism and cultural backgrounds (i.e., Eastern) are based on different, though related, cognitive control processes associated with different EF constructs. Results revealed a significant bilingualism effect on cognitive control processes measuring selective attention, switching, and inhibition; while an effect of culture was most pronounced on behavioral regulation/response inhibition. Contributions of bilingualism and cultural experiences on individual EF constructs across development are discussed.

Attention in Bilingual Children With Developmental Language Disorder

Purpose Attention and language are hypothesized to interact in bilingual children and in children with developmental language disorder (DLD). In children who are bilingual, attentional control may be enhanced by repeated experience regulating 2 languages. In children with DLD, subtle weaknesses in sustained attention may relate to impaired language processing. This study measured attentional control and sustained attention in monolingual and bilingual children with and without DLD in order to examine the potential influences of bilingualism and DLD, as well as their intersection, on attention. Method Monolingual English-only and bilingual Spanish-English children aged 6-8 years were categorized into participant groups based on eligibility testing and parent interviews. Parent interviews included standardized assessment of language environment and parent concern regarding language. Participants completed 2 nonlinguistic computerized assessments: a flanker task to measure attentional control and a continuous performance task to measure sustained attention. Results One hundred nine children met all eligibility criteria for inclusion in a participant group. Regression models predicting performance on the attention tasks were similar for both sustained attention and attentional control. For both tasks, DLD was a significant predictor, and bilingualism was not. Measuring bilingualism continuously using parent-reported exposure did not alter results. Conclusions This study found no evidence of a "bilingual cognitive advantage" on 2 types of attention among sequential Spanish-English bilingual children but also found a negative effect of DLD that was consistent across both types of attention and both bilingual and monolingual children. Results are consistent with the broader literature on subtle nonlinguistic deficits in children with DLD and suggest these deficits are minimally affected by diverse linguistic experience.

Self-Concepts in Reading and Spelling among Mono- and Multilingual Children: Extending the Bilingual Advantage

Cognitive representations and beliefs are what comprise an individual's self-concept. A positive self-concept is related to and influences academic achievement, and the relationship between a domain-specific self-concept and achievement in the same domain is positive and strong. However, insufficient attention has been paid to these issues among multilingual children. More importantly, since instruction strongly contributes to the development of metacognition and executive functions (EFs), and since the bilingual advantage hypothesis holds that the constant management of multiple languages entails benefits for EF, we bring together these important issues in the present study. We examine the relationship between domain-specific self-concepts and standardized assessment of reading and spelling competences against the background of potential differences in self-concept between monolingual and multilingual German children. While between-group comparisons revealed no significant differences for self-concept nor reading competency, monolinguals outperformed multilinguals in spelling. Correlations between domain-specific self-concepts and academic achievement in reading comprehension, reading fluency, and spelling were positive and significant for both groups. Regardless of language background, children's evaluations of their academic achievement (reading and spelling) were realistic. We argue, on a theoretical basis, that metacognition and EFs could facilitate a bilingual advantage and improve educational outcomes.

Do Bilingual Children Have an Executive Function Advantage? Results From Inhibition, Shifting, and Updating Tasks

Purpose

The purpose of this study was to examine differences in performance between monolingual and Spanish-English bilingual second graders (aged 7-9 years old) on executive function tasks assessing inhibition, shifting, and updating to contribute more evidence to the ongoing debate about a potential bilingual executive function advantage.

Method

One hundred sixty-seven monolingual English-speaking children and 80 Spanish-English bilingual children were administered 7 tasks on a touchscreen computer in the context of a pirate game. Bayesian statistics were used to determine if there were differences between the monolingual and bilingual groups. Additional analyses involving covariates of maternal level of education and nonverbal intelligence, and matching on these same variables, were also completed.

Results

Scaled-information Bayes factor scores more strongly favored the null hypothesis that there were no differences between the bilingual and monolingual groups on any of the executive function tasks. For 2 of the tasks, we found an advantage in favor of the monolingual group.

Conclusions

If there is a bilingual advantage in school-aged children, it is not robust across circumstances. We discuss potential factors that might counteract an actual advantage, including task reliability and environmental influences.

Bilingualism Narrows Socioeconomic Disparities in Executive Functions and Self-Regulatory Behaviors During Early Childhood: Evidence From the Early Childhood Longitudinal Study

Socioeconomic status (SES) and bilingualism have been shown to influence executive functioning during early childhood. Less is known, however, about how the two factors interact within an individual. By analyzing a nationally representative sample of approximately 18,200 children who were tracked from ages 5 to 7 across four waves, both higher SES and bilingualism were found to account for greater performance on the inhibition and shifting aspects of executive functions (EF) and self-regulatory behaviors in classroom. However, only SES reliably predicted verbal working memory. Furthermore, bilingualism moderated the effects of SES by ameliorating the detrimental consequences of low-SES on EF and self-regulatory behaviors. These findings underscore bilingualism's power to enrich executive functioning and self-regulatory behaviors, especially among underprivileged children.

Novice Readers: The Role of Focused, Selective, Distributed and Alternating Attention at the First Year of the Academic Curriculum

The ability to read depends on different cognitive skills. This study investigated the role of the main components of attention (selective attention, focused attention, distributed attention, and alternating attention) on the different dimensions of reading skills in novice readers. Participants were 288 Italian children, who attended the first year of primary school. Attention and reading skills (reading "comprehension," "accuracy," and "speed") were measured. Different components of attention influence each dimension of reading. Moreover, both the correctness and rapidity at which attention operates play a pivotal role in learning to read. Interestingly, selective attention is involved in all dimensions of reading. These findings may have educational and practical relevance. The early assessment of attention might favor the development of new strategies of intervention in dyslexic children and in children at risk of developing learning difficulties.

The bilingual adaptation: How minds accommodate experience

According to some estimates, more than half of the world's population is multilingual to some extent. Because of the centrality of language use to human experience and the deep connections between linguistic and nonlinguistic processing, it would not be surprising to find that there are interactions between bilingualism and cognitive and brain processes. The present review uses the framework of experience-dependent plasticity to evaluate the evidence for systematic modifications of brain and cognitive systems that can be attributed to bilingualism. The review describes studies investigating the relation between bilingualism and cognition in infants and children, younger and older adults, and patients, using both behavioral and neuroimaging methods. Excluded are studies whose outcomes focus primarily on linguistic abilities because of their more peripheral contribution to the central question regarding experience-dependent changes to cognition. Although most of the research discussed in the review reports some relation between bilingualism and cognitive or brain outcomes, several areas of research, notably behavioral studies with young adults, largely fail to show these effects. These discrepancies are discussed and considered in terms of methodological and conceptual issues. The final section proposes an account based on "executive attention" to explain the range of research findings and to set out an agenda for the next steps in this field. (PsycINFO Database Record