Sensorimotor processing in children and higher-cognitive processing in adults could determine how non-native phonemes are acquired. This study investigates how age-of-acquisition (AOA) and proficiency-level (PL) predict native-like perception of statistically dissociated L2 categories, i.e., within-category and between-category. In a similarity task, participants rated the level of similarity between pairs of English syllables from 1 (similar) to 4 (dissimilar). Early L2 acquisition predicts accurate within-categorization and high proficiency in late L2 acquisition predicts improved between-categorization. Our results suggest that the manner in which bilinguals learn to categorize non-native sounds depends on the cognitive processes available at the age of L2 exposure.

The aim of the current study was to examine the effects of bilingualism on letter and category fluency tasks. Participants were 1,600 monolingual and bilingual children from three cities in Iran: Tehran (Persian monolinguals), Tabriz (Turkish–Persian bilinguals), and Sanandaj (Kurdish–Persian bilinguals). We separately presented nine Persian letters and thirty-one categories to the participants, and asked them to generate as many words as possible using each of these initial letters and categories within a maximum of three minutes. Bilingual children generated more words than monolingual children in the letter fluency task; this effect was more pronounced in Grade 1 and for Turkish–Persian bilinguals. However, Persian monolinguals generated significantly more words than both bilingual groups in the category fluency task. Thus, bilingualism can be of both advantage and disadvantage, and produce a dissociative effect. We discuss the results on the basis of the specific nature and different cognitive demands of letter and category fluency tasks. We suggest that the degree of language proficiency of bilinguals should be considered as an important variable in future research on bilingualism.

This study investigated the role of domain-general inhibitory control in trilingual speech production. Taking an individual differences approach, we examined the relationship between performance on a non-linguistic measure of inhibitory control (the Simon task) and a multilingual language switching task for a group of fifty-six native English (L1) speakers learning French (L2) and Spanish (L3). Better inhibitory control was related to reduced switch costs, but only when switching into or out of the more dominant L1, where inhibitory control has been theorized to be most important (Green, 1998). The results provide evidence of a direct link between inhibitory control abilities and language switching capabilities, and suggest constraints on the conditions under which a domain-general inhibitory control mechanism supports language switching.

The goal of this study was to determine which linguistic aspects of second language speech are related to accent and which to comprehensibility. To address this goal, 19 different speech measures in the oral productions of 40 native French speakers of English were examined in relation to accent and comprehensibility, as rated by 60 novice raters and three experienced teachers. Results showed that both constructs were associated with many speech measures, but that accent was uniquely related to aspects of phonology, including rhythm and segmental and syllable structure accuracy, while comprehensibility was chiefly linked to grammatical accuracy and lexical richness.

Levy, Mc Veigh, Marful and Andreson (2007) found that naming pictures in L2 impaired subsequent recall of the L1 translation words. This was interpreted as evidence for a domain-general inhibitory mechanism (RIF) underlying first language attrition. Because this result is at odds with some previous findings and theoretical assumptions, we wanted to assess its reliability and replicate the experiment with various groups. Participants were first shown drawings along with their labels in the non-dominant language. Afterwards, they named 75% of these drawings in their first language or in their non-dominant language. Finally, participants’ memory of all L1 words was tested through the presentation of a rhyme-cue. Recall of L1 words was better after naming pictures in the non-dominant language compared to when the picture was not named at all. This result suggests that speaking a second language protects rather than harms the memory of our first language.

By administering a Stroop task to college-student bilinguals varied in self-rated first- (L1) and second-language (L2) proficiency, the current study examined the effects of L1 and L2 proficiencies on selective attention performance. We conducted ex-Gaussian analyses to capture the modal and positive-tail components of participants' reaction time distributions. Both L1 and L2 proficiencies were associated with a shift of reaction time distributions in incongruent trials, relative to congruent trials, and the tail size of reaction time distributions regardless of trial types. This suggests that bilinguals' L1 and L2 proficiencies could affect their Stroop performance via modulating their conflict resolution and goal maintenance abilities.

Crosslinguistic influence has been seen in bilingual adult and child learners when compared to monolingual learners. For speakers of Light Warlpiri and Gurindji Kriol there is no monolingual group for comparison, yet crosslinguistic influence can be seen in how the speakers resolve competition between case-marking and word order systems in each language. Light Warlpiri and Gurindji Kriol are two new Australian mixed languages, spoken in similar, yet slightly different, sociolinguistic contexts, and with similar, yet slightly different, argument marking systems. The different sociolinguistic situations and systems of argument marking lead to a difference in how speakers of each language interpret simple transitive sentences in a comprehension task. Light Warlpiri speakers rely on ergative case-marking as an indicator of agents more often than Gurindji Kriol speakers do. Conversely, Gurindji Kriol speakers rely on word order more often than Light Warlpiri speakers do.

English receptive vocabulary scores from 797 monolingual and 808 bilingual participants between the ages of 17 and 89 years old were aggregated from 20 studies to compare standard scores across language groups. The distribution of scores was unimodal for both groups but the mean score was significantly different, with monolinguals obtaining higher standard scores than bilinguals. Consistent with previous research, older adults had higher vocabulary scores than younger adults. The results are discussed in terms of the implications for theoretical conceptions of linguistic processing and clinical diagnosis in bilingual populations.

In this paper the prosodic structure of American Sign Language (ASL) narratives is analyzed in deaf native signers (L1-D), hearing native signers (L1-H), and highly proficient hearing second language signers (L2-H). The results of this study show that the prosodic patterns used by these groups are associated both with their ASL language experience (L1 or L2) and with their hearing status (deaf or hearing), suggesting that experience using co-speech gesture (i.e. gesturing while speaking) may have some effect on the prosodic cues used by hearing signers, similar to the effects of the prosodic structure of an L1 on an L2.

Chinese and English speakers seem to hold different conceptions of time which may be related to the different codings of time in the two languages. Employing a sentence–picture matching task, we have investigated this linguistic relativity in Chinese–English bilinguals varying in English proficiency and found that those with high proficiency performed differently from those with low proficiency. Additional monolingual English data, reported here, showed further that high-proficiency bilinguals performed similarly to the English monolinguals, suggesting that Chinese speakers’ sensitivity to the time of an action event might be modifiable according to the extent of their experience with a tensed language.

This article aims at revitalizing the debate concerning the measurement of language proficiency (LP) in the study of bilingualism (Grosjean, 1998). A review is presented of the way in which LP was measured in a corpus of 140 empirical papers published in volumes 1–14 (1998–2011) of the journal Bilingualism: Language and Cognition. In 55% of these papers, in which the assessment of LP as an independent or moderating variable was a necessary or preferred requirement, LP was not measured with an objective LP test. Seldom were participants’ LP scores used in explaining variance obtained in the dependent variable(s). After the discussion of some unresolved problems concerning cross-language comparisons of LP in bilinguals’ languages, recommendations are offered for the measurement of LP. One of the recommendations is that, in studies investigating between-group contrasts, researchers carefully consider the assessment of participants’ proficiency in the language(s) concerned, even in native-speaker comparison groups.