Bialystok E, Craik FIM, Luk G.
Cognitive control and lexical access in younger and older bilinguals. Journal of Experimental Psychology: Learning, Memory, and Cognition. 2008;(34) :859-873.
Publisher's VersionAbstractNinety-six participants, who were younger (20 years) or older (68 years) adults and either monolingual or bilingual, completed tasks assessing working memory, lexical retrieval, and executive control. Younger participants performed most of the tasks better than older participants, confirming the effect of aging on these processes. The effect of language group was different for each type of task: Monolinguals and bilinguals performed similarly on working memory tasks, monolinguals performed better on lexical retrieval tasks, and bilinguals performed better on executive control tasks, with some evidence for larger language group differences in older participants on the executive control tasks. These results replicate findings from individual studies obtained using only 1 type of task and different participants. The confirmation of this pattern in the same participants is discussed in terms of a suggested explanation of how the need to manage 2 language systems leads to these different outcomes for cognitive and linguistic functions.
Luk G, Bialystok E.
Common and distinct cognitive bases for reading in English--Cantonese bilinguals. Applied Psycholinguistics. 2008;(29) :269-289.
Publisher's VersionAbstractThe study explores the relationship between phonological awareness and early reading for bilingual children learning to read in two languages that use different writing systems. Participants were 57 Cantonese–English bilingual 6-year-olds who were learning to read in both languages. The children completed cognitive measures, phonological awareness tasks, and word identification tests in both languages. Once cognitive abilities had been controlled, there was no correlation in word identification ability performance across languages, but the correspondence in phonological awareness measures remained strong. This pattern was confirmed by a principal components analysis and hierarchical regression that demonstrated a different role for each phonological awareness factor in reading perfor- mance in each language. The results indicate that phonological awareness depends on a set of cognitive abilities that is applied generally across languages and that early reading depends on a common set of cognitive abilities in conjunction with skills specific to different writing systems.
Bialystok E, Craik FIM, Luk G.
Lexical access in bilinguals: Effects of vocabulary size and executive control. Journal of Neurolinguistics. 2008;(21) :522-538.
AbstractWe 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.
Emmorey K, Luk G, Pyers JE, Bialystok E.
The source of enhanced cognitive control in bilinguals: Evidence from bimodal bilinguals. Psychological Science. 2008;(19) :1201-1206.
Publisher's VersionAbstractBilinguals often outperform monolinguals on nonverbal tasks that require resolving conflict from competing alternatives. The regular need to select a target language is argued to enhance executive control. We investigated whether this enhancement stems from a general effect of bilingualism (the representation of two languages) or from a modality constraint that forces language selection. Bimodal bilinguals can, but do not always, sign and speak at the same time. Their two languages involve distinct motor and perceptual systems, leading to weaker demands on language control. We compared the performance of 15 monolinguals, 15 bimodal bilinguals, and 15 unimodal bilinguals on a set of flanker tasks. There were no group differences in accuracy, but unimodal bilinguals were faster than the other groups; bimodal bilinguals did not differ from monolinguals. These results trace the bilingual advantage in cognitive control to the unimodal bilingual’s experience controlling two languages in the same modality.