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Abstract

Bilingual experience has an impact on an individual’s linguistic processing and general cognitive abilities. The relation between these linguistic and non-linguistic domains, in turn, is mediated by individual linguistic proficiency and developmental changes that take place across the lifespan. This study evaluated this relationship by assessing inhibition skills, and verbal fluency in monolingual and bilingual school-aged children (Experiment 1), young adults (Experiment 2), and older adults (Experiment 3). Results showed that bilinguals outperformed monolinguals in the measure of inhibition, but only in the children and older adult age groups. With regards to verbal fluency, bilingual children outperformed their monolingual peers in the letter verbal fluency task, but no group differences were observed for the young and old adults. These findings suggest that bilingual experience leads to significant advantages in linguistic and non-linguistic domains, but only at the time points when these skills undergo developmental changes.

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... Introduction: Previous research has found that when bilingual and monolingual children are equated on English receptive vocabulary, bilingual children outperform monolingual children on verbal fluency tasks (e.g., Pino Escobar et al., 2018;Zeng et al., 2019). However, the locus of these differences in performance is poorly understood. ...
... A clearer picture emerges of the locus of bilingual and monolingual differences in category fluency when studies have accounted for receptive vocabulary knowledge. When bilinguals and monolinguals have similar English receptive vocabulary, there are no group differences on category fluency for both adults (Bialystok, Craik, & Luk, 2008;Luo et al., 2010) and children (Friesen et al., 2015;Zeng et al., 2019) in multiple studies. Pino Escobar et al. (2018) recently found that bilingual 7 and 8 year-old children, who were matched on English receptive vocabulary with monolingual peers, even outperformed monolinguals in the category fluency task. ...
... Pino Escobar et al. (2018) recently found that bilingual 7 and 8 year-old children, who were matched on English receptive vocabulary with monolingual peers, even outperformed monolinguals in the category fluency task. With respect to letter fluency, these same studies found that English receptive vocabulary-matched bilinguals generated more items than their monolingual peers (Bialystok et al., 2008b;Friesen et al., 2015;Luo et al., 2010;Pino Escobar et al., 2018;Zeng et al., 2019). The fact that multiple studies have observed greater performance levels by bilinguals in letter fluency relative to monolinguals suggests that bilinguals are recruiting additional cognitive processes to meet the task demands of the letter fluency condition (Friesen et al., 2015;Zeng et al., 2019). ...
Article
Introduction Previous research has found that when bilingual and monolingual children are equated on English receptive vocabulary, bilingual children outperform monolingual children on verbal fluency tasks (e.g., Pino Escobar et al., 2018; Zeng et al., 2019). However, the locus of these differences in performance is poorly understood. The current study investigated the linguistic and cognitive components that underlie verbal fluency performance in bilingual and English-speaking monolingual children. Methods Students in fourth and sixth grade (63 bilinguals and 31 monolinguals) performed both category and letter fluency tasks in English where they named members of provided categories in one-minute trials (e.g., animals, words that start with “F”, respectively). Participants also completed a battery of English language measures (e.g., English receptive vocabulary, English word reading fluency) and cognitive measures (e.g., fluid intelligence, working memory). Results Although monolinguals outperformed bilinguals on English receptive vocabulary, no group differences emerged on verbal fluency measures. When English receptive vocabulary served as a covariate, bilinguals generated significantly more items than monolinguals in the verbal fluency tasks. For monolinguals, only English receptive vocabulary accounted for unique variance in verbal fluency performance. However, for bilinguals, receptive vocabulary and fluid intelligence were significant predictors in both fluency tasks. Additionally, for bilinguals, fluid intelligence impacted the strength of the relationship between English receptive vocabulary and letter fluency performance; they were not significantly correlated for individuals with low cognitive ability and were strongly correlated for individuals with high cognitive ability. Conclusions Results suggest that unlike monolingual children, bilingual children recruit additional cognitive resources to meet the demands imposed by the verbal fluency task.
... Many studies have shown that bilinguals perform more poorly than monolinguals on linguistic tasks (e.g., Bialystok, 2009a), have a smaller vocabulary than monolinguals and produce fewer words in verbal fluency tasks (Zeng et al., 2019). These findings could be due to the lower use and the specificity of each language. ...
... In twenty-four studies were assessed both languages known by the bilingual participants. In three studies (Escobar et al., 2018;Dick et al., 2019;Zeng et al., 2019), objective assessments and self-report questionnaires were used. The use of both tools allows investigating both language proficiency (tests) and language use (self-report), two aspects that can contribute to a better description of the bilingual experience (Luk and Bialystok, 2013). ...
... Seven studies (Poarch and van Hell, 2012;Gathercole et al., 2014;Mohades et al., 2014;Ross and Melinger, 2017;Raudszus et al., 2018;Struys et al., 2018;Zeng et al., 2019) used the Simon Task (Simon and Wolf, 1963). In two studies (Poarch and van Hell, 2012;Raudszus et al., 2018), no significant differences emerged between the monolingual and the bilingual groups. ...
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The aim of this study was to compare oral fluency strategies of Spanish-English bilinguals in Spanish and English with Spanish and English monolinguals when given either phonemic (alphabetical) or semantic categorical cues. The use of grammatical words (words that play a grammatical function relating words within a sentence) or content words (words that have a meaning such as nouns, verbs, and adjectives) in the alphabetical categories is analyzed. This study also addresses the relation between productivity and the use of a semantic strategy to organize responses. Eighty-two right-handed participants (28 males and 54 females) with a mean age of 61.76 (SD = 9.30; range 50-84) and a mean educational level of 14.8 years (SD = 3.6; range 2-23) were selected. Forty-five of the subjects were English monolinguals, 18 were Spanish monolinguals, and 19 were Spanish-English bilinguals. Oral verbal fluency was tested asking subjects to generate words within phonemic (F, A, and S) and semantic (animals) categories. In the phonemic condition, performance of English and Spanish monolinguals was similar. Bilinguals produced significantly fewer words than English monolinguals in the categorical semantic condition but not in the phonological condition. In the phonological condition, English monolinguals generated significantly more grammatical words than Spanish monolinguals, and bilinguals produced a significantly higher number of grammatical words in English than in Spanish. Animal subcategories and semantic associations were similar in both languages for all groups. Results were discussed in terms of crosslinguistic differences in the recall of alphabetical words.
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The authors induced tip-of-the-tongue states (TOTs) for English words in monolinguals and bilinguals using picture stimuli with cognate (e.g., vampire, which is vampiro in Spanish) and noncognate (e.g., funnel, which is embudo in Spanish) names. Bilinguals had more TOTs than did monolinguals unless the target pictures had translatable cognate names, and bilinguals had fewer TOTs for noncognates they were later able to translate. TOT rates for the same targets in monolinguals indicated that these effects could not be attributed to target difficulty. Two popular TOT accounts must be modified to explain cognate and translatability facilitation effects, and cross-language interference cannot explain bilinguals' increased TOTs rates. Instead the authors propose that, relative to monolinguals, bilinguals are less able to activate representations specific to each language.
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Any mature field of research in psychology-such as short-term/working memory-is characterized by a wealth of empirical findings. It is currently unrealistic to expect a theory to explain them all; theorists must satisfice with explaining a subset of findings. The aim of the present article is to make the choice of that subset less arbitrary and idiosyncratic than is current practice. We propose criteria for identifying benchmark findings that every theory in a field should be able to explain: Benchmarks should be reproducible, generalize across materials and methodological variations, and be theoretically informative. We propose a set of benchmarks for theories and computational models of short-term and working memory. The benchmarks are described in as theory-neutral a way as possible, so that they can serve as empirical common ground for competing theoretical approaches. Benchmarks are rated on three levels according to their priority for explanation. Selection and ratings of the benchmarks is based on consensus among the authors, who jointly represent a broad range of theoretical perspectives on working memory, and they are supported by a survey among other experts on working memory. The article is accompanied by a web page providing an open forum for discussion and for submitting proposals for new benchmarks; and a repository for reference data sets for each benchmark. (PsycINFO Database Record
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The role of early bilingual experience in the development of skills in the general cognitive and linguistic domains remains poorly understood. This study investigated the link between these two domains by assessing inhibitory control processes in school-aged monolingual and bilingual children with similar English receptive vocabulary size. The participants, 8-year-old monolinguals and bilinguals, completed two Verbal Fluency Tasks (VFTs), letter and category, and two measures of inhibitory control. Results showed that bilinguals outperformed monolinguals on the VFTs, but performance was similar on the inhibitory control measures approaching ceiling for both monolingual and bilingual children. Importantly, it was shown that both vocabulary proficiency and general inhibitory control skills underlie monolingual and bilingual children's performance on VFTs. These results demonstrate that vocabulary proficiency plays a fundamental role in comparing monolingual and bilingual VFT performance. The bilingual advantage found in this study seems to have escaped previous studies that did not account for vocabulary size in populations of bilingual and monolingual school-aged children.
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Proficient bilinguals demonstrate slower lexical retrieval than comparable monolinguals. The present study tested predictions from two main accounts of this effect, the frequency-lag and competition hypotheses. Both make the same prediction for bilinguals but differ for trilinguals and for age differences. 200 younger or older adults who were monolingual, bilingual, or trilingual performed a picture naming task in English that included high and low frequency words. Naming times were faster for high than for low frequency words and, in line with frequency-lag, group differences were larger for low than high frequency items. However, on all other measures, bilinguals and trilinguals performed equivalently, and lexical retrieval differences between language groups did not attenuate with age, consistent with the competition view.
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Verbal fluency for semantic categories and phonological letters is frequently applied to studies of language and executive functions. Despite its popularity, it is still debated whether measures of semantic and phonological fluency reflect the same or distinct sets of cognitive processes. Word generation in the two task variants is believed to involve different types of search processes. Findings from the lesion and neuroimaging literature further suggest a stronger reliance of phonological and semantic fluency on frontal and temporal brain areas, respectively. This evidence for differential cognitive and neural contributions is, however, strongly challenged by findings from factor analyses, which have consistently yielded only one explanatory factor.
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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.
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Differences between monolingual and multilingual vocabulary development have been observed but few studies provide a longitudinal perspective on vocabulary development before and following school entry. This study compares vocabulary growth profiles of 106 multilingual children to 211 monolingual peers before and after school entry to examine whether: (1) school entry coincides with different rates of vocabulary growth compared to prior to school entry, (2) compared to monolingual peers, multilingual children show different vocabulary sizes or rates of vocabulary growth, (3) the age of onset of second-language acquisition for multilingual children is associated with vocabulary size or rate of vocabulary growth, and (4) the sociolinguistic context of the languages spoken by multilingual children is associated with vocabulary size or rate of vocabulary growth. Results showed increases in vocabulary size across time for all children, with a steeper increase prior to school entry. A significant difference between monolingual and multilingual children who speak a minority language was observed with regards to vocabulary size at school entry and vocabulary growth prior to school entry, but growth rate differences were no longer present following school entry. Taken together, results suggest that which languages children speak may matter more than being multilingual per se.
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This book sets a high standard for rigor and scientific approach to the study of bilingualism and provides new insights regarding the critical issues of theory and practice, including the interdependence of linguistic knowledge in bilinguals, the role of socioeconomic status, the effect of different language usage patterns in the home, and the role of schooling by single-language immersion as opposed to systematic training in both home and target languages. The rich landscape of outcomes reported in the volume will provide a frame for interpretation and understanding of effects of bilingualism for years to come.
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The verbal fluency task is a widely used neuropsychological test of word retrieval efficiency. Both category fluency (e.g., list animals) and letter fluency (e.g., list words that begin with F) place demands on semantic memory and executive control functions. However letter fluency places greater demands on executive control than category fluency, making this task well-suited to investigating potential bilingual advantages in word retrieval. Here we report analyses on category and letter fluency for bilinguals and monolinguals at four ages, namely, 7-year-olds, 10-year-olds, young adults, and older adults. Three main findings emerged: 1) verbal fluency performance improved from childhood to young adulthood and remained relatively stable in late adulthood; 2) beginning at 10-years-old, the executive control requirements for letter fluency were less effortful for bilinguals than monolinguals, with a robust bilingual advantage on this task emerging in adulthood; 3) an interaction among factors showed that category fluency performance was influenced by both age and vocabulary knowledge but letter fluency performance was influenced by bilingual status.
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Contemporary research on bilingualism has been framed by two major discoveries. In the realm of language processing, studies of comprehension and production show that bilinguals activate information about both languages when using one language alone. Parallel activation of the two languages has been demonstrated for highly proficient bilinguals as well as second language learners and appears to be present even when distinct properties of the languages themselves might be sufficient to bias attention towards the language in use. In the realm of cognitive processing, studies of executive function have demonstrated a bilingual advantage, with bilinguals outperforming their monolingual counterparts on tasks that require ignoring irrelevant information, task switching, and resolving conflict. Our claim is that these outcomes are related and have the overall effect of changing the way that both cognitive and linguistic processing are carried out for bilinguals. In this article we consider each of these domains of bilingual performance and consider the kinds of evidence needed to support this view. We argue that the tendency to consider bilingualism as a unitary phenomenon explained in terms of simple component processes has created a set of apparent controversies that masks the richness of the central finding in this work: the adult mind and brain are open to experience in ways that create profound consequences for both language and cognition.
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Bilingual experience is dynamic and poses a challenge for researchers to develop instruments that capture its relevant dimensions. The present study examined responses from a questionnaire administered to 110 heterogeneous bilingual young adults. These questions concern participants' language use, acquisition history and self-reported proficiency. The questionnaire responses and performances on standardized English proficiency measures were analyzed using factor analysis. In order to retain a realistic representation of bilingual experience, the factors were allowed to correlate with each other in the analysis. Two correlating factors were extracted, representing daily bilingual usage and English proficiency. These two factors were also related to self-rated proficiency in English and non-English language. Results were interpreted as supporting the notion that bilingual experience is composed of multiple related dimensions that will need to be considered in assessments of the consequences of bilingualism.
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Bilingualism may provide an advantage to older adults on inhibitory control tasks. This study examined the effects of bilingualism (balanced and non-balanced) on inhibitory control using simple and complex Simon tasks with samples of younger and older Spanish—English bilinguals (N = 125) and English monolinguals (N = 108). Results revealed a bilingual advantage on the simple task but not on the complex Simon task. Results suggest that bilingualism increases skills that are associated with selective attention when working memory demands are low.
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Previous research has shown that bilingual children perform better than comparable monolinguals on tasks requiring control of attention to inhibit misleading information. The present paper reports a series of studies that traces this processing difference into adulthood and eventually aging. The task used in all groups, from children to older adults, is the Simon task, a measure of stimulus-response incompatibility. The results showed that bilinguals performed better than monolinguals in early childhood, adulthood, and later adulthood. There was no difference in performance between monolinguals and bilinguals who were young adults, specifically university undergraduates. Our interpretation is that performance is at its peak efficiency for that group and bilingualism offers no further boost. The results are discussed in terms of the effect of bilingualism on control of attention and inhibition through the lifespan.
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The nature of bilingual cognitive processing advantages and disadvantages can be used to constrain models of bilingual language processing and to highlight aspects of cognitive processing that are critical for achieving and maintaining proficient bilingualism. We review some differences between bilinguals and monolinguals and consider whether or not skills known to influence monolingual language fluency, such as working memory capacity and suppression skills, may also be used to explain which individuals are successful in achieving proficiency in a second language and avoiding disadvantages associated with bilingualism. Our focus on working memory is motivated by both practical and theoretical reasons. First, much of the existing literature on individual differences in language processing has focused on working memory. Second, current research on working memory implicates suppression as the variable that underlies the predictive power of working memory measures, and suppression is a mechanism that very naturally relates to current models of bilingual language processing. Specifically, efficient suppression mechanisms may function to limit the amount of interfering information in working memory, thus increasing the apparent capacity of working memory and perhaps also decreasing cross-language interference. This perspective is based on recent developments in research on bilingualism that suggest both languages are always active and thus require the bilingual to use cognitive resources to control the relative levels of activation of the two languages. We suggest that two influential models of bilingual language processing predict a large role for suppression mechanisms in both achieving and maintaining proficient bilingualism. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
We report the results of two studies investigating lexical access in bilinguals. In Study 1, monolinguals performed better than bilinguals on tests of naming and letter fluency, but not on category fluency. When vocabulary size was considered, most of the effects disappeared or were reduced. In Study 2, a larger group of bilinguals was studied to compare the effect of vocabulary size, and a more restrictive version of the letter fluency task was used to increase executive processing involvement. In this case, bilinguals with matched vocabulary scores outperformed monolinguals on letter fluency, and bilinguals with lower vocabulary scores performed at the same level as monolinguals. The results are discussed in terms of the contributions of vocabulary size and executive control to performance on lexical retrieval tasks.
Article
Previous research has shown that bilingual children excel in tasks requiring inhibitory control to ignore a misleading perceptual cue. The present series of studies extends this finding by identifying the degree and type of inhibitory control for which bilingual children demonstrate this advantage. Study 1 replicated the earlier research by showing that bilingual children perform the Simon task more rapidly than monolinguals, but only on conditions in which the demands for inhibitory control were high. The next two studies compared performance on tasks that required inhibition of attention to a specific cue, like the Simon task, and inhibition of a habitual response, like the day-night Stroop task. In both studies, bilingual children maintained their advantage on tasks that require control of attention but showed no advantage on tasks that required inhibition of response. These results confine the bilingual advantage found previously to complex tasks requiring control over attention to competing cues (interference suppression) and not to tasks requiring control over competing responses (response inhibition).
Article
to examine racial differences in (a) the prevalence of financial exploitation and psychological mistreatment since turning 60 and in the past 6 months and (b) the experience-perpetrator, frequency, and degree of upset-of psychological mistreatment in the past 6 months. random digit dial telephone recruitment and population-based survey (telephone and in-person) of 903 adults aged 60 years and older in Allegheny County (Pittsburgh), Pennsylvania (693 non-African American and 210 African American). Covariates included sex, age, education, marital status, household composition, cognitive function, instrumental activities of daily living/activities of daily living difficulties, and depression symptoms. prevalence rates were significantly higher for African Americans than for non-African Americans for financial exploitation since turning 60 (23.0% vs. 8.4%) and in the past 6 months (12.9% vs. 2.4%) and for psychological mistreatment since turning 60 (24.4% vs. 13.2%) and in the past 6 months (16.1% vs. 7.2%). These differences remained once all covariates were controlled in logistic regression models. There were also racial differences in the experience of psychological mistreatment in the past 6 months. Risk for clinical depression was also a consistent predictor of financial exploitation and psychological mistreatment. although the results will need to be replicated in national surveys, the study suggests that racial differences in elder mistreatment are a potentially serious issue deserving of continued attention from researchers, health providers, and social service professionals.
Article
We use a time-course analysis to examine the roles of vocabulary size and executive control in bilinguals' verbal fluency performance. Two groups of bilinguals and a group of monolingual adults were tested in English with verbal fluency subtests from the Delis-Kaplan Executive Function System. The two bilingual groups were equivalent in their self-rated English proficiency but differed in levels of receptive and expressive vocabulary. We hypothesized that the difference between the two bilingual groups in vocabulary and between the monolingual and bilingual groups in executive control would lead to differences in performance on the category and letter fluency tests and dissociate the roles of vocabulary knowledge and executive control in verbal production. Bilinguals and monolinguals performed equivalently in category fluency, but the high-vocabulary bilingual group outperformed both monolinguals and low-vocabulary bilinguals in letter fluency. An analysis of the retrieval time-course functions in letter fluency showed dissociable effects of resources available at the initiation of the trial, considered to reflect vocabulary size, and ability to monitor and retrieve new items using a novel phonemic-based word searching strategy, considered to reflect executive control. The difference in slope of the best-fitting curves reflected enhanced executive control for both bilingual groups compared to monolinguals, whereas the difference in the starting point of the logarithmic functions reflected higher levels of vocabulary for high-vocabulary bilinguals and monolinguals compared to low-vocabulary bilinguals. The results are discussed in terms of the contributions of linguistic resources and executive control to verbal performance.
Article
We report two experiments exploring more in detail the bilingual advantage in conflict resolution tasks. In particular, we focus on the origin of the bilingual advantage on overall reaction times in the flanker task. Bilingual and monolingual participants were asked to perform a flanker task under different task versions. In Experiment 1, we used two low-monitoring versions where most of the trials were of just one type (either congruent or incongruent). In Experiment 2, we used two high-monitoring versions where congruent and incongruent trials were more evenly distributed. An effect of bilingualism in overall reaction times was only present in the high-monitoring condition. These results reveal that when the task at hand recruits a good deal of monitoring resources, bilinguals outperform monolinguals. This observation suggests that bilingualism may affect the monitoring processes involved in executive control.
Article
The present study used a behavioral version of an anti-saccade task, called the 'faces task', developed by [Bialystok, E., Craik, F. I. M., & Ryan, J. (2006). Executive control in a modified anti-saccade task: Effects of aging and bilingualism. Journal of Experimental Psychology: Learning, Memory, and Cognition, 32, 1341-1354] to isolate the components of executive functioning responsible for previously reported differences between monolingual and bilingual children and to determine the generality of these differences by comparing bilinguals in two cultures. Three components of executive control were investigated: response suppression, inhibitory control, and cognitive flexibility. Ninety children, 8-years old, belonged to one of three groups: monolinguals in Canada, bilinguals in Canada, and bilinguals in India. The bilingual children in both settings were faster than monolinguals in conditions based on inhibitory control and cognitive flexibility but there was no significant difference between groups in response suppression or on a control condition that did not involve executive control. The children in the two bilingual groups performed equivalently to each other and differently from the monolinguals on all measures in which there were group differences, consistent with the interpretation that bilingualism is responsible for the enhanced executive control. These results contribute to understanding the mechanism responsible for the reported bilingual advantages by identifying the processes that are modified by bilingualism and establishing the generality of these findings across bilingual experiences. They also contribute to theoretical conceptions of the components of executive control and their development.
Article
The "weaker links" hypothesis proposes that bilinguals are disadvantaged relative to monolinguals on speaking tasks because they divide frequency-of-use between two languages. To test this proposal we contrasted the effects of increased word use associated with monolingualism, language dominance, and increased age on picture naming times. In two experiments, younger and older bilinguals and monolinguals named pictures with high- or low-frequency names in English and (if bilingual) also in Spanish. In Experiment 1, slowing related to bilingualism and language dominance was greater for producing low- than high-frequency names. In Experiment 2, slowing related to aging was greater for producing low-frequency names in the dominant language, but when speaking the nondominant language, increased age attenuated frequency effects and age-related slowing was limited exclusively to high-frequency names. These results challenge competition based accounts of bilingual disadvantages in language production, and illustrate how between-group processing differences may emerge from cognitive mechanisms general to all speakers.
Article
Two studies are reported in which monolingual and bilingual children (Study 1) and adults (Study 2) completed a memory task involving proactive interference. In both cases, the bilinguals attained lower scores on a vocabulary test than monolinguals but performed the same on the proactive interference task. For the children, bilinguals made fewer intrusions from previous lists even though they recalled the same number of words. For the adults, bilinguals recalled more words than monolinguals when the scores were corrected for differences in vocabulary. In addition, there was a strong effect of vocabulary in which higher vocabulary participants recalled more words irrespective of language group. These results point to the important role of vocabulary in verbal performance and memory. They also suggest that bilinguals may compensate for weaker language proficiency with their greater executive control to achieve the same or better levels of performance as monolinguals.
Article
Word fluency has been shown to be reduced by left frontal lesions. The hypothesis is formulated that this is due to the coincidence of lesions in the left hemisphere entailing verbal deficits generally, and frontal lesions producing deficits in the capacity to suppress habitual behaviour in order to adapt to unusual situations. A test of word fluency and a modification of the Stroop-Test were given to 118 patients with circumscribed cerebral lesions. In the Stroop-Test the patients were faced with an increasing degree of conflict between a usual (verbal) category and an unsual category. The deficit in word fluency after left frontal lesions reported earlier is confirmed. Moreover, with increasing conflict between two categories in the Stroop-Test, left frontal lesions produce an increasing performance deficit as compared with lesions localized elsewhere in the brain. Finally, the correlations between performance in word fluency and in the Stroop-Test are highest in left frontal patients. These results corroborate the hypothesis of the role of the frontal lobe in the adaptation of behaviour to unsual situations, the left frontal lobe being of fundamental importance when verbal factors are involved.
Article
Research on spoken word production has been approached from two angles. In one research tradition, the analysis of spontaneous or induced speech errors led to models that can account for speech error distributions. In another tradition, the measurement of picture naming latencies led to chronometric models accounting for distributions of reaction times in word production. Both kinds of models are, however, dealing with the same underlying processes: (1) the speaker's selection of a word that is semantically and syntactically appropriate; (2) the retrieval of the word's phonological properties; (3) the rapid syllabification of the word in context; and (4) the preparation of the corresponding articulatory gestures. Models of both traditions explain these processes in terms of activation spreading through a localist, symbolic network. By and large, they share the main levels of representation: conceptual/semantic, syntactic, phonological and phonetic. They differ in various details, such as the amount of cascading and feedback in the network. These research traditions have begun to merge in recent years, leading to highly constructive experimentation. Currently, they are like two similar knives honing each other. A single pair of scissors is in the making.
Article
Spanish-English bilinguals and English monolinguals completed 12 semantic, 10 letter, and 2 proper name fluency categories. Bilinguals produced fewer exemplars than monolinguals on all category types, but the difference between groups was larger (and more consistent) on semantic categories. Bilinguals and monolinguals produced the same number of errors across all category types. The authors discuss 2 accounts of the similarities and differences between groups and the interaction with category type, including (a) cross-language interference and (b) relatively weak connections in the bilingual lexical system because of reduced use of words specific to each language. Surprisingly, bilinguals' fluency scores did not improve when they used words in both languages. This result suggests that voluntary language switching incurs a processing cost.