Bilinguals know virtually twice as many words as monolinguals. They seem to effortlessly use the right word in the right context, and can even switch back and forth between languages with little obvious cost. Nonetheless, evidence suggests that maintaining more than one language in a single cognitive system introduces processing differences, and some bilingual effects on speaking increase as bilinguals age. An obvious (and popular) account of the bilingual effect on speaking is that knowing two words to express any given concept introduces competition between languages. However, we propose that differences in patterns of language use alone are sufficient to explain some of the consequences of bilingualism for speaking. We investigate bilingual effects on speaking with the goal of constraining models of bilingualism and of language production in all speakers (Section I). We hypothesize that bilinguals differ from monolinguals in circumscribed ways that are either related to their different patterns of language use or arise because the same tasks sometimes present bilinguals and monolinguals with different challenges. We test the predictions of two different accounts of how bilingualism should affect single word production, sentence level fluency, and speech errors (including tip-of-the-tongue or TOT states, whole word substitutions, and sound errors). We also aim to develop models of bilingual control and to identify processing mechanisms that may be unique to bilinguals by introducing a previously uninvestigated type of language switching and by explicitly manipulating the degree of dual-language activation (Section II). The mechanisms we consider make different predictions about how aging should affect bilingual performance, and we test these predictions as a means of developing models of bilingualism and accounts of age-related changes in cognitive performance. By identifying the generality of the bilingual effect, we determine what constitutes normal performance for young and aging bilinguals in a variety of tasks, and will identify the conditions that allow bilinguals of different types to function as fluently as they can. The proposed experiments will constrain models of monolingual and bilingual language production, models of bilingual and cognitive control, and accounts of age-related processing changes including both processing disadvantages (e.g., age-related decline in cognitive control) but also processing advantages (e.g., older adults have increased experience with words). ? ? ?

National Institute of Health (NIH)
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Research Project (R01)
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Special Emphasis Panel (ZRG1-BBBP-T (03))
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Mccardle, Peggy D
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University of California San Diego
Schools of Medicine
La Jolla
United States
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Kleinman, Daniel; Gollan, Tamar H (2018) Inhibition accumulates over time at multiple processing levels in bilingual language control. Cognition 173:115-132
Ivanova, Iva; Branigan, Holly P; McLean, Janet F et al. (2017) Do you what I say? People reconstruct the syntax of anomalous utterances. Lang Cogn Neurosci 32:175-189
Ivanova, Iva; Ferreira, Victor S; Gollan, Tamar H (2017) Form Overrides Meaning When Bilinguals Monitor for Errors. J Mem Lang 94:75-102
Li, Chuchu; Goldrick, Matthew; Gollan, Tamar H (2017) Bilinguals' twisted tongues: Frequency lag or interference? Mem Cognit 45:600-610
Kleinman, Daniel; Gollan, Tamar H (2016) Speaking Two Languages for the Price of One: Bypassing Language Control Mechanisms via Accessibility-Driven Switches. Psychol Sci 27:700-14
Ivanova, Iva; Murillo, Mayra; Montoya, Rosa I et al. (2016) Does Bilingual Language Control Decline in Older Age? Linguist Approaches Biling 6:86-118
Weissberger, Gali H; Gollan, Tamar H; Bondi, Mark W et al. (2015) Language and task switching in the bilingual brain: Bilinguals are staying, not switching, experts. Neuropsychologia 66:193-203
Gollan, Tamar H; Starr, Jennie; Ferreira, Victor S (2015) More than use it or lose it: the number-of-speakers effect on heritage language proficiency. Psychon Bull Rev 22:147-55
Ivanova, Iva; Salmon, David P; Gollan, Tamar H (2014) Which language declines more? longitudinal versus cross-sectional decline of picture naming in bilinguals with Alzheimer's disease. J Int Neuropsychol Soc 20:534-46
Gollan, Tamar H; Kleinman, Daniel; Wierenga, Christina E (2014) What's easier: doing what you want, or being told what to do? Cued versus voluntary language and task switching. J Exp Psychol Gen 143:2167-95

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