Independent effects of bilingualism and socioeconomic status on language ability and executive functioning

One hundred and seventy-five children who were 6-years old were assigned to one of four groups that differed in socioeconomic status (SES; working class or middle class) and language background (monolingual or bilingual). The children completed tests of nonverbal intelligence, language tests assessing receptive vocabulary and attention based on picture naming, and two tests of executive functioning. All children performed equivalently on the basic intelligence tests, but performance on the language and executive functioning tasks was influenced by both SES and bilingualism. Middle-class children outperformed working-class children on all measures, and bilingual children obtained lower scores than monolingual children on language tests but higher scores than monolingual children on the executive functioning tasks. There were no interactions with either group factors or task factors. Thus, each of SES and bilingualism contribute significantly and independently to children’s development irrespective of the child’s level on the other factor.     

Bilingual experience and executive functioning in young children

Advanced inhibitory control skills have been found in bilingual speakers as compared to monolingual controls (Bialystok, 1999). We examined whether this effect is generalized to an unstudied language group (Spanish-English bilingual) and multiple measures of executive function by administering a battery of tasks to 50 kindergarten children drawn from three language groups: native bilinguals, monolinguals (English), and English speakers enrolled in second-language immersion kindergarten. Despite having significantly lower verbal scores and parent education/income level, Spanish-English bilingual children's raw scores did not differ from their peers. After statistically controlling for these factors and age, native bilingual children performed significantly better on the executive function battery than both other groups. Importantly, the relative advantage was significant for tasks that appear to call for managing conflicting attentional demands (Conflict tasks); there was no advantage on impulse-control (Delay tasks). These results advance our understanding of both the generalizability and specificity of the compensatory effects of bilingual experience for children's cognitive development.     

Word Mapping and Executive Functioning in Young Monolingual and Bilingual Children

The effect of bilingualism on the cognitive skills of young children was investigated by comparing performance of 162 children who belonged to one of two age groups (approximately 3- and 4.5-year-olds) and one of three language groups on a series of tasks examining executive control and word mapping. The children were monolingual English speakers, monolingual French speakers, or bilinguals who spoke English and one of a large number of other languages. Monolinguals obtained higher scores than bilinguals on a receptive vocabulary test and were more likely to demonstrate the mutual exclusivity constraint, especially at the younger ages. However, bilinguals obtained higher scores than both groups of monolinguals on three tests of executive functioning: Luria's tapping task measuring response inhibition, the opposite worlds task requiring children to assign incongruent labels to a sequence of animal pictures, and reverse categorization in which children needed to reclassify a set of objects into incongruent categories after an initial classification. There were no differences between the groups in the attentional networks flanker task requiring executive control to ignore a misleading cue. This evidence for a bilingual advantage in aspects of executive functioning at an earlier age than previously reported is discussed in terms of the possibility that bilingual language production may not be the only source of these developmental effects.     

Bilingual advantage,bidialectal advantage or neither? Comparing performance across three tests of executive function in middle childhood

When bilinguals speak, both fluent language systems become activated in parallel and exert an influence on speech production. As a consequence of maintaining separation between the two linguistic systems, bilinguals are purported to develop enhanced executive control functioning. Like bilinguals, individuals who speak two dialects must also maintain separation between two linguistic systems, albeit to a lesser degree. Across three tests of executive function, we compared bilingual and bidialectal children's performance to that of a monolingual control group. No evidence for a bidialectal advantage was found. However, in line with a growing number of recent partial and failed replications, we observed a significant bilingual advantage only in one measure in one task. This calls the robustness of the bilingual advantage into question. A comprehensive review of studies investigating advantages of inhibitory control and cognitive flexibility in bilingual children reveals that the bilingual advantage is likely to be both task and sample specific, and the interaction between these factors makes qualification of the effect challenging. These findings highlight the importance of tracking the impact of dual linguistic systems across the lifespan using tasks calibrated for difficulty across different ages.     

Attentional control in early and later bilingual children

We examined differences in attentional control among school-age children who were monolingual English speakers, early Spanish-English bilinguals (who began speaking both languages by age 3), and later Spanish-English bilingual children (who began speaking English after age 3). Children's attentional control was tested using the Attention Network Test (ANT). All language groups performed equally on ANT networks; however, when controlling for age and verbal ability, groups differed significantly on reaction time. Early bilingual children responded faster on the ANT compared to both monolingual and later bilingual children, suggesting an attentional monitoring advantage for early bilinguals. These results add to evidence of advantaged cognitive functioning among bilinguals and are consistent with the possibility that children who begin speaking a second language earlier in childhood have greater advantages, due either to effects of acquiring a second language earlier or to longer duration of bilingual experience.     

The effect of childhood bilingualism on episodic and semantic memory tasks

Kormi-Nouri, Moniri and Nilsson (2003) demonstrated that Swedish-Persian bilingual children recalled at a higher level than Swedish monolingual children, when they were tested using Swedish materials. The present study was designed to examine the bilingual advantage of children who use different languages in their everyday life but have the same cultural background and live in their communities in the same way as monolingual children. In four experiments, 488 monolingual and bilingual children were compared with regard to episodic and semantic memory tasks. In experiments 1 and 2 there were 144 boys and 144 girls in three school groups (aged 9-10 years, 13-14 years and 16-17 years) and in three language groups (Persian monolingual, Turkish-Persian bilingual, and Kurdish-Persian bilingual). In experiments 3 and 4, there were 200 male students in two school groups (aged 9-10 years and 16-17 years) and in two language groups (Persian monolingual and Turkish-Persian bilingual). In the episodic memory task, children learned sentences (experiments 1-3) and words (Experiment 4). Letter and category fluency tests were used as measures of semantic memory. To change cognitive demands in memory tasks, in Experiment 1, the integration of nouns and verbs within sentences was manipulated by the level of association between verb and noun in each sentence. At retrieval, a recognition test was used. In experiments 2 and 3, the organization between sentences was manipulated at encoding in Experiment 2 and at both encoding and retrieval in Experiment 3 through the use of categories among the objects. At retrieval, free recall or cued recall tests were employed. In Experiment 4, the bilingual children were tested with regard to both their first and their second language. In all four experiments, a positive effect of bilingualism was found on episodic and semantic memory tasks; the effect was more pronounced for older than younger children. The bilingual advantage was not affected by changing cognitive demands or by using first/second language in memory tasks. The present findings support the cross-language interactivity hypothesis of bilingual advantage.     

A Comparative Study of Shifting Ability,Inhibitory Control and Working Memory in Monolingual and Bilingual Children

It is now well documented that the linguistic development of bilingual children is, in many respects, different from that of their monolingual peers. Yet, there is substantial evidence in cognitive psychology that the effect of bilingualism is not merely restricted to the linguistic competence of individuals. Recent literature on bilingualism suggests that certain aspects of children’s cognitive development can be positively affected by the bilingual experience. The aim of the present study was to investigate the potential effects of bilingual experience on young children’s executive processing. A total of 67 preschool children belonging to two groups including 36 Persian–Turkish bilingual children and 31 Persian monolingual children participated in the study. They were matched for their verbal proficiency and then were compared on three executive function tasks including shifting ability, inhibitory control and working memory. Results showed that bilingual children outperformed monolinguals on both shifting and inhibitory control tasks. However, both groups performed similarly on working memory tasks. The findings are interpreted in terms of the enhanced ability of bilingual children in various executive functions processing.     

What did Simon say? Revisiting the bilingual advantage

Bilingual children often outperform monolingual children in tasks of cognitive control. This advantage may be a consequence of the fact that bilinguals have more practice controlling attention due to an ongoing need to manage two languages. However, existing evidence is limited because possible differences in ethnicity and socioeconomic status have not been properly controlled. To address this issue, we administered the Simon task to bilingual and monolingual children of identical ethnic and socioeconomic backgrounds. Bilingual and monolingual children performed identically, whereas children from higher SES families were advantaged relative to children from lower SES families. Controlling differences in SES and ethnicity may attenuate the bilingual advantage in cognitive control.     

The missing explanation of the false‐belief advantage in bilingual children: a longitudinal study

Bilingual preschoolers often perform better than monolingual children on false‐belief understanding. It has been hypothesized that this is due to their enhanced executive function skills, although this relationship has rarely been tested or supported. The current longitudinal study tested whether metalinguistic awareness was responsible for this advantage. Further, we examined the contributions of both executive functioning and language ability to false‐belief understanding by including multiple measures of both. Seventy‐eight children (n = 40 Spanish‐English bilingual; age M = 49.29, SD = 7.38 and, n = 38 English monolingual; age M = 47.75, SD = 6.86) were tested. A year later the children were tested again (n = 22 bilingual, n = 25 monolingual). The results indicated that language and executive function (inhibitory control) at time 1 were related to false belief in monolinguals at time 2. In contrast, bilinguals' metalinguistic performance at time 1 was the sole predictor of false belief at time 2. The different linguistic and cognitive profiles of monolinguals and bilinguals may create different pathways for their development of false‐belief understanding. A video abstract of this article can be viewed at: https://youtu.be/vILn2gKjFxw     

Executive control in older Welsh monolinguals and bilinguals

Evidence for a bilingual advantage in executive control has led to the suggestion that being bilingual might protect against late-life cognitive decline. We assessed the performance of socially homogeneous groups of older (≥60 years) bilingual Welsh/English (n?=?50) and monolingual English (n?=?49) speakers on a range of executive control tasks yielding 17 indices for comparison. Effect sizes (>.2) favoured monolinguals on 10 indices, with negligible differences observed on the remaining 7 indices. Univariate analyses indicated that monolinguals performed significantly better on 2 of 17 indices. Multivariate analysis indicated no significant overall differences between the two groups in performance on executive tasks. Older Welsh bilinguals do not show a bilingual advantage in executive control, and where differences are observed, these tend to favour monolinguals. A possible explanation may lie in the nature of the socio-linguistic context and its influence on cognitive processing in the bilingual group.     

Speed of processing, anticipation, inhibition and working memory in bilinguals

Literature on the so-called bilingual advantage is directed towards the investigation of whether the mastering of two languages fosters cognitive skills in the non-verbal domain. The present study aimed to evaluate whether the bilingual advantage in non-verbal skills could be best defined as domain-general or domain-specific, and, in the latter case, at identifying the basic cognitive skills involved. Bilingual and monolingual participants were divided into two different age groups (children, youths) and were tested on a battery of elementary cognitive tasks which included a choice reaction time task, a go/no-go task, two working memory tasks (numbers and symbols) and an anticipation task. Bilingual and monolingual children did not differ from each other except for the anticipation task, where bilinguals were found to be faster and more accurate than monolinguals. These findings suggest that anticipation, which has received little attention to date, is an important cognitive domain which needs to be evaluated to a greater extent both in bilingual and monolingual participants.     

Bilingualism, aging, and cognitive control: evidence from the Simon task

Previous work has shown that bilingualism is associated with more effective controlled processing in children; the assumption is that the constant management of 2 competing languages enhances executive functions (E. Bialystok, 2001). The present research attempted to determine whether this bilingual advantage persists for adults and whether bilingualism attenuates the negative effects of aging on cognitive control in older adults. Three studies are reported that compared the performance of monolingual and bilingual middle-aged and older adults on the Simon task. Bilingualism was associated with smaller Simon effect costs for both age groups; bilingual participants also responded more rapidly to conditions that placed greater demands on working memory. In all cases the bilingual advantage was greater for older participants. It appears, therefore, that controlled processing is carried out more effectively by bilinguals and that bilingualism helps to offset age-related losses in certain executive processes.     

Are bilingual children better at ignoring perceptually misleading information? A novel test

Does speaking more than one language help a child perform better on certain types of cognitive tasks? One possibility is that bilingualism confers either specific or general cognitive advantages on tasks that require selective attention to one dimension over another (e.g. Bialystok, 2001 ; Hilchey & Klein, 2011 ). Other studies have looked for such an advantage but found none (e.g. Morton & Harper, 2007 ; Paap & Greenberg, 2013 ). The present study compared monolingual and bilingual children's performance on a numerical discrimination task, which required children to ignore area and attend to number. Ninety‐two children, ages 3 to 6 years, were asked which of two arrays of dots had ‘more dots’. Half of the trials were congruent, where the numerically greater array was also larger in total area, and half were incongruent, where the numerically greater array was smaller in total area. All children performed better on congruent than on incongruent trials. Older children were more successful than younger children at ignoring area in favor of number. Bilingual children did not perform differently from monolingual children either in number discrimination itself (i.e. identifying which array had more dots) or at selectively attending to number. The present study thus finds no evidence of a bilingual advantage on this task for children of this age.     

Language and cognitive shifting: evidence from young monolingual and bilingual children

The relationship between language and cognitive shifting in young children was examined. Specifically, second language experiences from infancy as well as individual differences in monolingual language experience may affect performances on the Dimensional Change Card Sort Task. 54 Japanese-French bilingual children and two groups of Japanese monolingual children participated (ns = 18). One monolingual group was matched to the bilingual group on verbal ability and chronological age (VC monolingual group) and the other group was matched by chronological age but had higher verbal ability (C monolingual group). The results showed that the groups of children who were bilingual and monolingual with higher verbal ability performed the task significantly better than matched monolingual children. Language experiences may affect cognitive set shifting in young children.     

Math and Memory in Bilingual Preschoolers: The Relations Between Bilingualism,Working Memory,and Numerical Knowledge

ABSTRACT

Bilingual children exhibit enhanced working memory (WM) skill relative to monolingual children, which could have implications for early mathematics development. Competency in mathematics is supported by conceptual and procedural mathematical knowledge, and numerical knowledge is in turn supported by underlying cognitive processes such as WM. Building on this evidence, we investigated whether bilingual preschoolers demonstrated, relative to monolingual peers, enhanced performance on WM and greater numerical knowledge. We examined the role of WM in numerical understanding for both monolingual and bilingual children. Participants were 4- and 5-year old children (74) recruited from preschools serving families from a range of socioeconomic, racial, and ethnic backgrounds. Participants completed a nonverbal WM task and a range of numerical-knowledge measures, specifically numeral identification, addition, symbolic magnitude comparison, and nonsymbolic magnitude comparison tasks. Results revealed that bilingual children outperformed monolingual peers on WM even after controlling for age and socioeconomic status (SES). Bilingual children also demonstrated greater performance on addition and numeral identification tasks. For all tasks except numeral identification, WM predicted children’s performance on numerical knowledge measures. We discuss results in terms of the possible unique cognitive and academic advantages bilingual children may have.     

The relationship between bilingualism and selective attention in young adults: Evidence from an ambiguous figures task

Previous research has shown that bilinguals outperform monolinguals on a variety of tasks that have been described as involving executive functioning, but the precise mechanism for those effects or a clear definition for “executive function” is unknown. This uncertainty has led to a number of studies for which no performance difference between monolingual and bilingual adults has been detected. One approach to clarifying these issues comes from research with children showing that bilinguals were more able than their monolingual peers to perceive both interpretations of an ambiguous figure, an ability that is more tied to a conception of selective attention than to specific components of executive function. The present study extends this notion to adults by assessing their ability to see the alternative image in an ambiguous figure. Bilinguals performed this task more efficiently than monolinguals by requiring fewer cues to identify the second image. This finding has implications for the role of selective attention in performance differences between monolinguals and bilinguals.     

A bilingual advantage for episodic memory in older adults

The ability to remember events—referred to as episodic memory—is typically subject to decline in older adulthood. Episodic memory decline has been attributed in part to less successful executive functioning, which may hinder an older adult's ability to implement controlled encoding and retrieval processes. Since bilingual older adults often show more successful executive functioning than monolinguals, they may be better able to maintain episodic memory. To examine this hypothesis, we compared bilingual and monolingual older adults on a picture scene recall task (assessing episodic memory) and a Simon task (assessing executive functioning). Bilinguals exhibited better episodic memory than their monolingual peers, recalling significantly more items overall. Within the bilingual group, earlier second language acquisition and more years speaking two languages were associated with better recall. Bilinguals also demonstrated higher executive functioning, and there was evidence that level of executive functioning was related to memory performance. Results indicate that extensive practice controlling two languages may benefit episodic memory in older adults.     

Theory of Mind and Executive Functions in Young Bilingual Children

Few studies have explored the relationship between theory of mind (ToM), executive function (EF), and bilingualism at the same time. In this study 14 young bilingual children were compared with monolingual children on a test battery composed of 5 ToM tests, 5 EF tests, and 1 test of general language ability. The result showed that despite significantly lower verbal ability, the bilingual children outperformed the monolingual ones on tests of EF. There were no differences in ToM performance. The authors argue that there is a strong relationship between bilingualism and EF, but, contrary to results from earlier studies, they could not find any relationship between bilingualism and ToM. EF did not predict ToM performance. Lack of a significant relationship could be due to the children's young age and consequently their low scores on the ToM tasks.     

A bilingual advantage in visual language discrimination in infancy

The origins of the bilingual advantage in various cognitive tasks are largely unknown. We tested the hypothesis that bilinguals' early capacities to track their native languages separately and learn about the properties of each may be at the origin of such differences. Spanish-Catalan bilingual and Spanish or Catalan monolingual infants watched silent video recordings of French-English bilingual speakers and were tested on their ability to discern when the language changed from French to English or vice versa. The infants' performance was compared with that of previously tested French-English bilingual and English monolingual infants. Although all groups of monolingual infants failed to detect the change between English and French, both groups of bilingual infants succeeded. These findings reveal that bilingual experience can modulate the attentional system even without explicit training or feedback. They provide a basis for explaining the ontogeny of the general cognitive advantages of bilinguals.     

Reasoning about other people's beliefs: bilinguals have an advantage

Bilingualism can have widespread cognitive effects. In this article we investigate whether bilingualism might have an effect on adults' abilities to reason about other people's beliefs. In particular, we tested whether bilingual adults might have an advantage over monolingual adults in false-belief reasoning analogous to the advantage that has been observed with bilingual children. Using a traditional false-belief task coupled with an eye-tracking technique, we found that adults in general suffer interference from their own perspective when reasoning about other people's beliefs. However, bilinguals are reliably less susceptible to this egocentric bias than are monolinguals. Moreover, performance on the false-belief task significantly correlated with performance on an executive control task. We argue that bilinguals' early sociolinguistic sensitivity and enhanced executive control may account for their advantage in false-belief reasoning.