Despite increasing attention to bilingualism – conferences, publications, grants – linguists are as far as ever from reaching consensus. Is code-switching the alternation between two equally activated languages or is it the insertion of elements from a source language into a recipient language? Can and should we distinguish borrowing and code-switching of single words? Is there grammatical convergence between bilinguals’ two languages and does code-switching promote it? Since the first accounts of the structure of code-switching in the 1970s, the same questions have been readdressed with astoundingly little, if any, cumulative advances. Scientific progress has been obstructed by polemic debate, often fueled by elicited judgments, which may display random error (Labov, 1996), or reports of the behavior of stray individuals, which are uninterpretable in the absence of knowledge of the systematic community pattern (Labov, 2006/1966, p. 5).

This commentary on Mayberry and Kluender (2017) considers the geometry of the function relating Age of Acquisition (AoA) to L2 attainment, the effects of multilingual exposure on one's native language(s) and, briefly, the role of education in language learning.

Extending the paradigm in L1 acquisition, scholars have begun to investigate whether participants’ domain-general ability to represent, encode, and integrate spectral and temporal dimensions of sounds (i.e., auditory processing) could be a potential determinant of the outcomes of post-pubertal L2 speech learning. The current study set out to test the hypothesis that auditory processing makes a unique contribution to L2 speech acquisition, for 70 Japanese classroom learners of English with different levels of L2 proficiency when biographical backgrounds (length of instruction and immersion) and memory abilities (working, declarative, and procedural memory) are controlled for. Auditory processing loaded onto modality-general capacities to represent and incorporate anchor stimuli (relative to target stimuli) into long-term memory in an implicit fashion, but dissociated from explicit abilities to remember, associate, and elaborate sensory information. Auditory processing explained a small-to-medium amount of variance in L2 speech learning, even after the other potentially confounding variables were statistically factored out.

Bilinguals’ emotions can vary in intensity with the language of a stimulus. Yet, extant research has somewhat surprisingly accepted inconsistent results from implicit nonverbal and explicit verbal emotion measures. To date, it is unclear if this inconsistency recurs to conceptual or methodological differences. We therefore investigated if squeezing a handheld dynamometer is a valid nonverbal, “visceral” alternative to self-reported language-dependent feelings by comparing explicit ratings to neuro-physiological emotional reactions. We replicated two pupillometry experiments inducing language-dependent emotions through sentence reading (Study 1) and listening to narrative video commercials (Study 2) of low and high emotionality in the first or second language. Pupillometry confirmed that bilinguals are more sensitive to the low-high emotionality contrast in their first than second language. Grip force (but not duration) mirrored these findings, whereas verbal ratings did not. We thus recommend grip force as a new attentional, nonverbal measure for bilingualism research.

Prediction is an important part of language processing. An open question is to what extent people predict language in challenging circumstances. Here we tested the limits of prediction by asking bilingual Dutch native speakers to interpret Dutch sentences into their English counterparts. In two visual world experiments, we recorded participants’ eye movements to co-present visual objects while they engaged in interpreting tasks (consecutive and simultaneous interpreting). Most participants showed anticipatory eye movements to semantically-related upcoming target words in their L1 source language during both consecutive and simultaneous interpretation. A quarter of participants during simultaneous interpretation however did not move their eyes, an extremely unusual participant behaviour in visual world studies. Overall, the findings suggest that most people predict in the source language under challenging interpreting situations. Further work is required to understand the causes of the absence of (anticipatory) eye movements during simultaneous interpretation in a substantial subset of individuals.

Being bilingual confers certain behavioral effects. Determining their precise origin is of utmost importance given the need to avoid unjust misattribution of labels such as “bilingual (dis)advantage” to people's bilingual experiences. To this end, this systematic PRISMA-based review aims to shed light on the social and sociolinguistic origins of bilingualism-related behavioral effects. Analyzing 368 studies, we find that 73.41% of the 267 studies that report such effects attribute them either to sociolinguistic factors alone or to the interaction of sociolinguistic and cognitive factors. Linking the two fronts, type of effect and origin of effect, we find a previously unreported correlation: Studies that find evidence for bilingual disadvantages are more likely to claim a sociolinguistic origin, while studies that report advantages are more likely to link their findings to a cognitive origin. We discuss these results and present the key components of a sociolinguistic theory of the origin of bilingual effects.

Studies of copular forms are extremely relevant to issues in philosophy, psychology, and linguistics. Psychologists have recently argued that the most distinctive aspect of human language is its combinatorial nature (e.g., Gentner, 2003; Spelke, 2003). They argue that this linguistic component might be what separates human from animal cognition. As combinatorial elements, copular forms have no equal. However, as the quote from Bertrand Russell implies, copular forms are multi-dimensional and complex. A full understanding of their use, linguistic variation, acquisition, and relation to cognition is a formidable task. While other papers in this special-issue volume of Bilingualism: Language and Cognition will address the different syntactic and semantic functions carried by these forms, in this commentary, I will focus on the relation between the acquisition of copular forms and cognitive development, or more specifically on the development of categorization.

Malay (Rumi) is alphabetic and has a transparent, agglutinative system of affixation. We manipulated language-specific junctural phonetics in Malay and English to investigate whether morphophonemic L1-knowledge influences L2-processing. A morpheme decision task, “Does this <nonword> sound like a mono- or bi-morphemic English word?”, was developed by crossing English Transitional Probability (high vs. low) with Malay Transitional Possibility (possible vs. impossible). The data for Malay-L1/English-L2 adults (N = 21) provide clear and reliable empirical evidence of L1-to-L2 morphophonemic transfer: Participants were more accurate at identifying transitional boundaries in English when they are also possible in Malay. Pedagogical implications are discussed.

A surprisingly large part of the population of the world is at least bilingual. The question as to how people are able to control their language system is an important one and has been a topic for highly active research in recent years. Until now, models have been quite simplistic, but Green places his model in a wider framework of attention and control, drawing our attention to the fact that the mechanisms involved in language control share basic properties with the systems in other cognitive domains. Green introduces the (not language-specific) supervisory attentional system in combination with language task schemas which make it possible to adapt to the situation in which the bilingual system is functioning. Models of bilingual processing should be able to explain how lexical processing is affected by, among others, task demands (see also Dijkstra, van Jaarsveld, and ten Brinke, 1998). By adding a general mechanism of attentional control that is independently motivated by general cognitive mechanisms, Green has enriched his previous model considerably. In what follows we will first make some general remarks about the model Green proposes. In the second part we will discuss some recent results from our group that nicely tie in with some of the basic properties of the model outlined by Green.

This study investigated how second language speakers use syntactic and semantic cues in processing complex sentences. Turkish speakers of English, native speakers of English and native speakers of Turkish participated in a self-paced reading experiment, a read-aloud task and a pen-and-paper questionnaire in their relevant languages. The participants’ working memory capacity was also measured. The results supported the primacy of syntax view for native speakers of Turkish and English (Frazier & Fodor, 1978). Both groups of native speakers primarily used syntactic cues in their on-line decisions; semantic information influenced later decisions only. The second language speakers, however, used semantic cues in both their initial and later decisions, with evidence for accessing complex syntactic representations. The results are taken to support the view that native and non-native speakers weight linguistic cues differentially (Cunnings, 2017). The potential reasons for differential cue-retrieval in the first and second language are discussed.

Differential affective processing has been widely documented for bilinguals: L1 affective words elicit higher levels of arousal and stronger emotionality ratings than L2 affective words (Pavlenko, 2012). In this study, we focus on two closely related Chinese languages, Mandarin and Cantonese, whose affective lexicons are highly overlapping, with shared lexical items that only differ in pronunciation across languages. We recorded L1 Cantonese – L2 Mandarin bilinguals’ pupil responses to auditory tokens of Cantonese and Mandarin affective words. Our results showed that Cantonese–Mandarin bilinguals had stronger pupil responses when the affective words were pronounced in Cantonese (L1) than when the same words were pronounced in Mandarin (L2). The effect was most evident in taboo words and among bilinguals with lower L2 proficiency. We discuss the theoretical implications of the findings in the frameworks of exemplar theory and models of the bilingual lexicon.

Very little is known about the processes underlying second language (L2) speakers’ understanding of written metaphors and similes. Moreover, most of the theories on figurative language comprehension do not consider reader-related factors. In the study, we used eye-tracking to examine how native Finnish speakers (N = 63) read written English nominal metaphors (“education is a stairway”) and similes (“education is like a stairway”). Identical topic–vehicle pairs were used in both conditions. After reading, participants evaluated familiarity of each pair. English proficiency was measured using the Bilingual-language Profile Questionnaire and the Lexical Test for Advanced Learners of English. The results showed that readers were more likely to regress within metaphors than within similes, indicating that processing metaphors requires more processing effort than processing similes. The familiarity of a metaphor and L2 English proficiency modulated this effect. The results are discussed in the light of current theories on figurative language processing.

Mayberry and Kluender (2017) present an important and compelling argument that in order to understand critical periods (CPs) in language acquisition, it is essential to disentangle studies of late first language (L1) acquisition from those of second language (L2) acquisition. Their primary thesis is that timely exposure to an L1 is crucial for establishing language circuitry, thus providing a foundation on which an L2 can build. They note that while there is considerable evidence of interference from the L1 on acquisition of the L2 – especially in late L2 learners (as in our work on cascading influences on phonetic category learning and visual language discrimination, e.g., Werker & Hensch, 2015 and Weikum, Vouloumanos, Navarra, Soto-Faraco, Sebastián-Gallés & Werker, 2013, respectively) – there are other examples of ways in which the L1 can scaffold L2 acquisition. Mayberry and Kluender take this evidence of L1 scaffolding L2 as undermining the value of considering CPs as useful in understanding L2 acquisition.

It is well-known that native English speakers sometimes erroneously accept subject-verb agreement violations when there is a number-matching attractor (e.g., *The key to the cabinets were…). Whether bilinguals whose L1 lacks number agreement are prone to such interference is unclear, given previous studies that report conflicting findings using different structures, participant groups, and experimental designs. To resolve the conflict, we examined highly proficient Korean–English bilinguals’ susceptibility to agreement attraction, comparing prepositional phrase (PP) and relative clause (RC) modifiers in a speeded acceptability judgment task and a speeded forced-choice comprehension task. The bilinguals’ judgments revealed attraction with RCs but not with PPs, while reaction times indicated attraction with both structures. The results therefore showed L2 attraction in all measures, with the consistent exception of judgments for PPs. We argue that this supports an overall native-like agreement processing mechanism, augmented by an additional monitoring mechanism that filters explicit judgments in simple structures.

Cunnings' keynote offers a new perspective on L2 processing by casting L1–L2 differences in terms of the memory system. One advantage of this approach is that it makes use of cue-based memory retrieval, a framework that has given rise to a wealth of research on L1 processing. However, there remain some questions about the evidence-base and predictions of the account, as well as conceptual challenges to its implementation.