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. KeywordsSpanish; aging; bilingualism; frequency effect; picture naming In trying to find the words we need to express our thoughts, it is much easier to retrieve and say the names of things that we talk about very often (e.g., cups) than the names of things that we don't talk about as often (e.g., carafes). Although nobody will argue with this point, there has been some debate with respect to the precise mechanism of frequency effects in language processing models (e.g., Murray & Forster, 2004), and whether frequency itself -or one of many variables that are correlated with frequency (e.g., AoA, length) -determines what makes frequently used words easier to access than infrequently used words (e.g., Gernsbacher, 1984). People who regularly speak more than one language provide a unique opportunity to investigate the relationship between frequency of use and lexical accessibility.Bilinguals know roughly twice as many words as monolinguals (assuming bilinguals know a word in each language for most lexicalized concepts). Despite the approximately doubled load, bilinguals seem to effortlessly use the right word in the right context, and can even switch back Please address editorial comments to: Tamar H. Gollan, Department of Psychiatry, University of California, San Diego, 9500 Gilman Drive, 0949, La Jolla, CA 92093-0949, fax: 858-622-1017, e-mail: tgollan@ucsd.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. and forth between languages with little obvious cost....

This study investigated correspondence between different measures of bilingual language proficiency contrasting self-report, proficiency interview, and picture naming skills. Fifty-two young (Experiment 1) and 20 aging (Experiment 2) Spanish-English bilinguals provided self-ratings of proficiency level, were interviewed for spoken proficiency, and named pictures in a Multilingual Naming Test (MINT, and in Experiment 1 also the Boston Naming Test; BNT). Self-ratings, proficiency interview, and the MINT did not differ significantly in classifying bilinguals into language-dominance groups, but naming tests (especially the BNT) classified bilinguals as more English-dominant than other measures. Strong correlations were observed between measures of proficiency in each language and language-dominance, but not degree of balanced bilingualism (index scores). Depending on the measure, up to 60% of bilinguals scored best in their self-reported non-dominant language. The BNT distorted bilingual assessment by underestimating ability in Spanish. These results illustrate what self-ratings can and cannot provide, illustrate the pitfalls of testing bilinguals with measures designed for monolinguals, and invite a multi-measure goal driven approach to classifying bilinguals into dominance groups.

Bilinguals named pictures in their dominant language more slowly (and with more errors) than did monolinguals. In contrast, bilinguals named the same pictures as quickly as did monolinguals on the fifth presentation (in Experiment 2) and classified them (as human made or natural) as quickly and accurately as did monolinguals (in Experiment 1). In addition, bilinguals retrieved English picture names more quickly if they knew the name in both Spanish and English (on the basis of a translation test that bilinguals completed after the timed tasks), and monolingual response times for the same materials suggested that this finding was not obtained simply because names that were easier to translate were easier in general. These findings suggest that bilinguals differ from monolinguals at a postconceptual processing level, that implicit activation of lexical representations in the nontarget language can facilitate retrieval in the target language, and that being bilingual is analogous to having a lexicon full of lower frequency words, relative to monolinguals.