The relation between bilingualism and cognition is informative about the connection between language and mind. From the perspective of language, the question is how bilingualism might help or hinder cognition – narrowly interpreted here as executive function. From the perspective of higher cognition, the question is what kinds of experiences improve executive function. Reported cognitive benefits from bilingualism range from none to substantial as a function of age, type of bilingualism (e.g., life-long balanced vs later-onset or infrequent use of the other language), syntactic relation between the two languages, socio-economic and immigrant status, task, and laboratory. To understand the variability and inconsistencies in results with bilingualism, I analyze concepts of executive function and cognitive reserve and examine the range of factors (such as active video game playing, education, musical training, and aerobic exercise) that are known to correlate with or to improve executive function. I suggest that a) “executive function” is a complex set of cognitive processes, the components of which are sometimes minimally correlated with each other, depending on the task; b) bilingualism is inconsistently correlated with superior executive function and delayed onset of dementia; c) all speakers (mono- or bilingual) have non-linguistic ways of improving executive function; and d) benefits from bilingualism – and all cognitively challenging activities – are inconsistent because individuals vary in the number and kinds of experiences they have that promote superior executive function.

Sentence comprehension in second language (L2) learners was examined using event-related brain potentials (ERPs). Native Japanese speakers who had learned German as a second language after puberty listened to German sentences which were either correct, semantically incorrect, syntactically incorrect or both semantically and syntactically incorrect. Brain responses were registered while participants listened to these sentences. Grammaticality judgments required after each sentence revealed that their overall performance was not perfect but clearly above chance. When comparing the L2-learners' brain responses to those of native listeners, a variety of differences were observed. Whereas semantically incorrect sentences showed an ERP pattern similar to that of native listeners (a centro-parietal N400-effect), correct sentences elicited a greater positivity in L2-learners than in native listeners, possibly in reflection of greater difficulties in syntactic integration. For sentences containing a phrase structure violation, L2-learners did not show significant modulations of the syntax-related ERP components usually seen in native listeners (i.e. the early anterior negativity and the P600). Furthermore, sentences containing a pure semantic or a combined syntactic and semantic violation elicited a late right anterior-central negativity, an effect which has not been observed for native language processing. The topography of the effect may suggest that these additional processes are based on conceptual-semantic rather than on lexical-semantic aspects.

The purpose of this paper is to draw on recent studies of bilingualism and emotions to argue for three types of modifications to the current models of the bilingual lexicon. The first modification involves word categories: I will show that emotion words need to be considered as a separate class of words in the mental lexicon, represented and processed differently from abstract and concrete words. The second modification involves conceptual representations: I will demonstrate that emotion concepts vary across languages and that bilinguals' concepts may, in some cases, be distinct from those of monolingual speakers. The third modification involves emotionality: I will argue that emotionality is an important feature of the bilingual lexicon, where different languages and word types display different levels of emotionality. I will also show how differential emotionality affects code-switching and language choice in bi- and multilinguals.

The findings from a number of recent studies indicate that, even in cases of successful bilingual first language acquisition, the possibility remains of a certain degree of crosslinguistic influence when the choice between syntactic options is affected by discourse pragmatics. In this study we focussed on the use of referring expressions, prime candidates to test the interaction between syntax and pragmatics, and we compared the distribution of subjects and objects in the Italian and English of a bilingual child (1;10–4;6) with that of two groups of MLUw-matched monolinguals. All arguments were coded for syntactic function and for a number of discourse pragmatic features predicted to affect their realisation. Our main prediction was that unidirectional crosslinguistic influence might occur for the English–Italian bilingual child with respect to pronominal subject and object use after the instantiation of the C system. Specifically we predicted that in Italian the bilingual child might use overt pronominal subjects in contexts where monolinguals would use a null subject, and that he might use postverbal strong object pronouns in Italian instead of preverbal weak pronominal clitics. Conversely, we did not expect the overall proportion of overt objects, whether noun phrases or pronouns, to vary crosslinguistically as objects are always obligatorily overt in both languages regardless of discourse pragmatics. Our results confirmed these predictions, and corroborated the argument that crosslinguistic influence may occur in bilingual first language acquisition in specific contexts in which syntax and pragmatics interact.

The purpose of this study was to determine if different language measures resulted in the same classifications of language dominance and proficiency for a group of bilingual pre-kindergarteners and kindergarteners. Data were analyzed for 1029 Spanish–English bilingual pre-kindergarteners who spanned the full range of bilingual language proficiency. Parent questionnaires were used to quantify age of first exposure and current language use. Scores from a short test of semantic and morphosyntactic development in Spanish and English were used to quantify children's performance. Some children who were in the functionally monolingual range based on interview data demonstrated minimal knowledge of their other languages when tested. Current use accounted for more of the variance in language dominance than did age of first exposure. Results indicate that at different levels of language exposure children differed in their performance on semantic and morphosyntax tasks. These patterns suggest that it may be difficult to compare the results of studies that employ different measures of language dominance and proficiency. Current use is likely to be a useful metric of bilingual development that can be used to build a comprehensive picture of child bilingualism.

Young English-speaking monolingual and bilingual adults were examined for English proficiency, language use history, and performance on a flanker task. The bilinguals, who were about twenty years old, were divided into two groups (early bilinguals and late bilinguals) according to whether they became actively bilingual before or after the age of ten years. Early bilinguals and monolinguals demonstrated similar levels of English proficiency, and both groups were more proficient in English than late bilinguals. In contrast, early bilinguals produced the smallest response time cost for incongruent trials (flanker effect) with no difference between monolinguals and late bilinguals. Moreover, across the whole sample of bilinguals, onset age of active bilingualism was negatively correlated with English proficiency and positively correlated with the flanker effect. These results suggest a gradient in which more experience in being actively bilingual is associated with greater advantages in cognitive control and higher language proficiency.

An eye tracking experiment examined how exposure to a second language (L2) influences sentence parsing in the first language. Forty-four monolingual Spanish speakers, 24 proficient Spanish–English bilinguals with limited immersion experience in the L2 environment and 20 proficient Spanish–English bilinguals with extensive L2 immersion experience read temporarily ambiguous constructions. The ambiguity concerned whether a relative clause (RC) that appeared after a complex noun phrase (NP) was interpreted as modifying the first or the second noun in the complex NP (El policía arrestó a la hermana del criado que estaba enferma desde hacía tiempo). The results showed that whereas the Spanish monolingual speakers and the Spanish–English bilinguals with limited exposure reliably attached the relative clause to the first noun, the Spanish–English bilingual with extensive exposure attached the relative to the second noun. Results are discussed in terms of models of sentence parsing most consistent with the findings.

A series of three lexical decision experiments showed that interlingual homographs may be recognized faster than, slower than, or as fast as monolingual control words depending on task requirements and language intermixing. In Experiment 1, Dutch bilingual participants performed an English lexical decision task including English/Dutch homographs, cognates, and purely English control words. Reaction times to interlingual homographs were unaffected by the frequency of the Dutch reading and did not differ from monolingual controls. In contrast, cognates were recognized faster than controls. In Experiment 2, Dutch participants again performed an English lexical decision task on homographs, but, apart from nonwords, Dutch words were included which required a “no” reaction. Strong inhibition effects were obtained which depended on the relative frequency difference of the two readings of the homograph. These turned into frequency-dependent facilitation effects in Experiment 3, where participants performed a general lexical decision task, responding “yes” if a word of either language was presented. It is argued that bilingual word recognition models can only account for the series of experiments if they explain how lexical processing is affected by task demands and stimulus list composition.

A key aspect of higher cognitive function is the ability to switch rapidly and efficiently between alternative modes of response where this is appropriate behaviourally. Such suppression appears to be highly dependent upon the integrity of the prefrontal cortex, yet other cortical areas are likely to be necessary to implement response switching. Language switching in bilingual speakers is a clear example of a task in which response switching is required. Functional brain imaging studies have demonstrated parietal cortex activation during repeated language switching within a translation task. Here we used event-related dense-sensor EEG recording techniques to examine the time course of language switching during a visually cued naming task in which bilingual participants named digits in either their first or second language. Switch-related modulation of ERP components was evident over parietal and frontal cortices, and in the latter case showed an asymmetry across first and second languages. Correspondence with a frontal ERP component found when suppressing manual responding in a Go/No-Go reaction time task may imply that similar inhibitory mechanisms are involved in both response suppression and language switching.

This article elucidates the Typological Primacy Model (TPM; Rothman, 2010, 2011, 2013) for the initial stages of adult third language (L3) morphosyntactic transfer, addressing questions that stem from the model and its application. The TPM maintains that structural proximity between the L3 and the L1 and/or the L2 determines L3 transfer. In addition to demonstrating empirical support for the TPM, this article articulates a proposal for how the mind unconsciously determines typological (structural) proximity based on linguistic cues from the L3 input stream used by the parser early on to determine holistic transfer of one previous (the L1 or the L2) system. This articulated version of the TPM is motivated by argumentation appealing to cognitive and linguistic factors. Finally, in line with the general tenets of the TPM, I ponder if and why L3 transfer might obtain differently depending on the type of bilingual (e.g. early vs. late) and proficiency level of bilingualism involved in the L3 process.

This study investigates whether age of onset of bilingualism has an effect on ultimate attainment, and documents incomplete acquisition and attrition of tense/aspect morphology in Spanish. A group of 20 monolingual Spanish speakers, 31 US-born bilinguals, and 8 Latin America-born bilinguals participated in the study. Sixteen of the US-born participants were simultaneous bilinguals who had been exposed to Spanish and English from ages 0 to 3, the remaining 15 learned English between ages 4 to 7 (early child L2 learners), and the Latin-America-born bilinguals learned English between 8 and 12 years of age (late child L2 learners). Results of an oral production, a written completion, and two meaning-interpretation tasks showed that the simultaneous bilingual and the early child L2 groups differed significantly from monolingual Spanish speakers, while only a few individuals in the late child L2 group showed erosion with some aspects. Results suggest that morpho-phonological spell-outs and semantic features of functional categories are affected by incomplete acquisition and language loss, and that many of the patterns of divergence found resemble stages of second language acquisition.

This paper investigates the role of amount of current and cumulative exposure in bilingual development and ultimate attainment by exploring the extent to which simultaneous bilingual children's knowledge of grammatical gender is affected by current and previous amount of exposure, including in the early years. Elicited production and grammaticality judgement data collected from 136 English–Dutch-speaking bilingual children aged between three and 17 years are used to examine the lexical and grammatical aspects of Dutch gender, viz. definite determiners and adjectival inflection. It is argued that the results are more consistent with a rule-based than a piecemeal approach to acquisition (Blom, Polišenskà & Weerman, 2008a; Gathercole & Thomas, 2005, 2009), and that non-target performance on the production task can be explained by the Missing Surface Inflection Hypothesis (Haznedar & Schwartz, 1997; Prévost & White, 2000; Weerman, Duijnmeijer & Orgassa, 2011).

This research examines whether an individual's linguistic knowledge, either as a speaker of a particular language or as a bilingual, influences theory of mind development. Three- and four-year-old English monolinguals, Mandarin Chinese monolinguals, and Mandarin-English bilinguals were given appearance-reality, level 2 perspective-taking, and false-belief tasks. All children were tested twice, a week apart; the bilinguals were tested in each of their languages. The 4-year-olds in each group performed significantly better than the corresponding 3-year-olds. Both monolingual groups performed similarly on the tasks, and the bilinguals performed significantly better than the monolingual groups, although when the two testing times were examined separately, they had only a near-significant tendency to perform better at the second testing time. Possible explanations for this evidence of a bilingual advantage are greater inhibitory control, greater metalinguistic understanding, and a greater sensitivity to sociolinguistic interactions with interlocutors.

With a growing interest in heritage languages from researchers of bilingualism and linguistic theory, the field of heritage-language studies has begun to build on its empirical foundations, moving toward a deeper understanding of the nature of language competence under unbalanced bilingualism. In furtherance of this trend, the current work synthesizes pertinent empirical observations and theoretical claims about vulnerable and robust areas of heritage language competence into early steps toward a model of heritage-language grammar. We highlight two key triggers for deviation from the relevant baseline: the quantity and quality of the input from which the heritage grammar is acquired, and the economy of online resources when operating in a less dominant language. In response to these triggers, we identify three outcomes of deviation in the heritage grammar: an avoidance of ambiguity, a resistance to irregularity, and a shrinking of structure. While we are still a ways away from a level of understanding that allows us to predict those aspects of heritage grammar that will be robust and those that will deviate from the relevant baselines, our hope is that the current work will spur the continued development of a predictive model of heritage language competence.

In our research we addressed the question what the relationship is between phonological short-term and working memory capacity and performance in an end-of-year reading, writing, listening, speaking and use of English test. The participants of our study were 121 secondary school students aged 15–16 in the first intensive language training year of a bilingual education program in Hungary. The participants performed a non-word repetition test and took a Cambridge First Certificate Exam. Fifty students were also tested with a backward digit span test, measuring their working memory capacity. Our study indicates that phonological short-term memory capacity plays a different role in the case of beginners and pre-intermediate students in intensive language learning. The backward digit span test correlated very highly with the overall English language competence, as well as with reading, listening, speaking and use of English (vocabulary and grammar) test scores.

In this study we address the question of how lexical selection is achieved by bilingual speakers during speech production. Specifically, we test whether there is competition between the two lexicons of a bilingual during lexical access. In two picture–word interference experiments we explore the performance of two groups of bilinguals, English–Spanish and Spanish–English proficient bilinguals while naming pictures either in their L1 (Spanish) or in their L2 (Spanish). Picture naming was facilitated when the name of the picture and the distracter word were the “same”, regardless of the language in which the distracter was printed: same-language (e.g., mesa–mesa [table in Spanish]) or different-language pairs (e.g., mesa–table). The magnitude of this facilitatory effect was similar when naming in L1 (Experiment 1) and in L2 (Experiment 2). We also found that naming latencies were slower when the distracter word was semantically related to the picture's name (e.g., mesa–chair), regardless of the language in which the distracter was printed. The results suggest that there is no competition between the two lexicons of a bilingual during lexical access for production. This interpretation favors a model of lexical access in which lexical selection is language-specific both when speaking in L1 and in L2.

The language history questionnaire (LHQ) is an important tool for assessing the linguistic background of bilinguals or second language learners and for generating self-reported proficiency in multiple languages. Previously we developed a generic LHQ based on the most commonly asked questions in published studies (Li, Sepanski & Zhao, 2006). Here we report a new web-based interface (LHQ 2.0) that has more flexibility in functionality, more accuracy in data recording, and more privacy for users and data. LHQ 2.0 achieves flexibility, accuracy, and privacy by using dynamic web-design features for enhanced data collection. It allows investigators to dynamically construct individualized LHQs on the fly and allows participants to complete the LHQ online in multiple languages. Investigators can download and delete the LHQ results and update their user and experiment information on the web. Privacy issues are handled through the online assignment of a unique ID number for each study and password-protected access to data.

The computational BIA+ model (Dijkstra & Van Heuven, 2002) has provided a useful account for bilingual word recognition, while the verbal (pre-quantitative) RHM (Kroll & Stewart, 1994) has often served as a reference framework for bilingual word production and translation. According to Brysbaert and Duyck (2010), a strong need is felt for a unified implemented account of bilingual word comprehension, lexical-semantic processing, and word production. With this goal in mind, we built a localist-connectionist model, called Multilink, which integrates basic assumptions of both BIA+ and RHM. It simulates the recognition and production of cognates (form-similar translation equivalents) and non-cognates of different lengths and frequencies in tasks like monolingual and bilingual lexical decision, word naming, and word translation production. It also considers effects of lexical similarity, cognate status, relative L2-proficiency, and translation direction. Model-to-model comparisons show that Multilink provides higher correlations with empirical data than both IA and BIA+ models.

Speech–sign or “bimodal” bilingualism is exceptional because distinct modalities allow for simultaneous production of two languages. We investigated the ramifications of this phenomenon for models of language production by eliciting language mixing from eleven hearing native users of American Sign Language (ASL) and English. Instead of switching between languages, bilinguals frequently produced code-blends (simultaneously produced English words and ASL signs). Code-blends resembled co-speech gesture with respect to synchronous vocal–manual timing and semantic equivalence. When ASL was the Matrix Language, no single-word code-blends were observed, suggesting stronger inhibition of English than ASL for these proficient bilinguals. We propose a model that accounts for similarities between co-speech gesture and code-blending and assumes interactions between ASL and English Formulators. The findings constrain language production models by demonstrating the possibility of simultaneously selecting two lexical representations (but not two propositions) for linguistic expression and by suggesting that lexical suppression is computationally more costly than lexical selection.

Recent years have seen a surge in research comparing bilinguals to monolinguals, yet synthesizing this literature is complicated by the diversity of language and social backgrounds behind these dichotomous labels. The current study examines the labels and descriptions reported in 186 studies comparing bilinguals and monolinguals published between 2005–2015 in order to understand how bilingualism has been operationalized and to describe the degree to which different facets of bilingual experience are reported. Proficiency and usage were the most frequently reported features (77% and 79%), followed by language history (67%) and the language of schooling (60%). However, less than half of the studies measured proficiency objectively or reported proportional usage, and even less – 30% – described the sociolinguistic context from which the sample was drawn. Given the increase in language contact due to globalization, more transparent and comprehensive reporting of participant characteristics is critical to building our understanding of how bilingualism affects experience.