Substantial research has examined cognition in aging bilinguals. However, less work has investigated the effects of aging on language itself in bilingualism. In this article I comprehensively review prior research on this topic, and interpret the evidence in light of current theories of aging and theories of bilingualism. First, aging indeed appears to affect bilinguals’ language performance, though there is considerable variability in the trajectory across adulthood (declines, age-invariance, and improvements) and in the extent to which these trajectories resemble those found in monolinguals. I argue that these age effects are likely explained by the key opposing forces of increasing experience and cognitive declines in aging. Second, consistent with some theoretical work on bilingual language processing, the grammatical processing mechanisms do not seem to change between younger and older bilingual adults, even after decades of immersion. I conclude by discussing how future research can further advance the field.

This study examined the extent to which language-switching practice enhanced L2 learners’ L2 grammatical processing by improving language selection abilities. Thirty-six English-speaking learners of French completed the same language-switching practice of L1 and L2 sentences, but received different types of pre-practice explicit information (EI) designed to address L2 learning difficulties resulting from crosslinguistic influence: one group (n = 17) received EI about English–French differences for viewpoint aspect, and a second group (n = 19) received EI about viewpoint aspect in French only. This design investigated the extent to which pre-practice linguistic knowledge moderated the effectiveness of the language-switching practice. Longitudinal analyses showed that increasing amounts of practice improved language selection abilities (increased accuracy, reduced reaction time costs), but only for learners who received EI about L1-L2 differences. These findings that language-switching was moderated by type of pre-practice EI have important implications for theories of L2 learning and instruction.

A longstanding question in the second language acquisition literature is whether late second language (L2) learners process grammatical structures in a native-like manner. Here, we use Time Frequency Representation (TFR) analysis to test morpho-syntactic processing of clitic pronouns in native and late L2 learners of Spanish. The TFR results show overall similar power decreases in theta, alpha, and beta frequencies in both groups. Critically, the observed oscillatory effects persisted in time for native Spanish speakers, but declined earlier for L2 learners. We discuss the results using cell-assembly theory models for language processing (e.g., Pulvermüller, 1999) that posit a biphasic time-course for neural assemblies consisting of an early ignition (recognition) and a later reverberation (re-processing) phase. We propose a working hypothesis for L2 processing in tune with a cell-assembly theory suggesting that the length of the reverberation phase could be a distinguishing feature between native and L2 processing.

This study extends research on morphological processing in late bilinguals to a rarely examined language type, Semitic, by reporting results from a masked-priming experiment with 58 non-native, advanced, second-language (L2) speakers of Hebrew in comparison with native (L1) speakers. We took advantage of a case of ‘pure morphology’ in Hebrew, the so-called binyanim, which represent (essentially arbitrary) morphological classes for verbs. Our results revealed a non-native priming pattern for the L2 group, with root-priming effects restricted to non-finite prime words irrespective of binyanim type. We conclude that root extraction in L2 Hebrew word recognition is less sensitive to both morphological and morphosyntactic cues than in the L1, in line with the Shallow-Structure Hypothesis of L2 processing.

This paper provides a concise overview of the cross-modal priming methodology, it presents a selection of key studies to illustrate how this method can be used to address lexical and syntactic processing and discusses advantages and disadvantages, along with issues that need to be taken into consideration when designing studies that address sentence processing in bilinguals.

It has been suggested that bilinguals learn additional languages ‘better’ than monolinguals. However, evidence is sparse, particularly for grammar. We examined behavioral and neural correlates of learning an additional (artificial) language in early Mandarin–English bilinguals, compared to English monolinguals. Following grammar instruction, participants practiced comprehension and production, and judged grammaticality at low and high proficiency while event-related potentials (ERPs) were acquired. Bilinguals and monolinguals did not differ on behavioral measures, but showed distinct ERP patterns. At low proficiency only bilinguals showed a P600, a common ERP correlate of syntactic processing in native speakers of languages. At high proficiency both groups showed P600s, though the monolinguals also evidenced an anterior positivity not typically found in native speakers of languages during syntactic processing. These findings suggest that, even without bilingual/monolingual behavioral differences, bilinguals show ERP patterns for an additional language that are more similar to those of native speakers of languages.

This special issue began as a conference on Bilingual and Multilingual Interaction at Bangor University in 2012. The papers collected here all have novel elements, either because of their innovative methods, their unusual data, or their unexpected findings. They present findings from studies of bilinguals speaking six different pairs of languages, and use a range of methods including experiments, naturalistic observation and auditory judgment data. Despite the differences in subject matter and methodological approaches, all the papers demonstrate that bilinguals draw on resources which are different from those of monolinguals. They show that the two languages spoken by bilinguals have clearly discernible effects on one another, and that these effects can potentially be enhancing. Future research will no doubt build on the studies presented here and extend our understanding of cross-language effects in bilingual production and comprehension.

How do late proficient bilinguals process morphosyntactic and lexical-semantic information in their non-native language (L2)? How is this information represented in the L2 mental lexicon? And what are the neural signatures of L2 morphosyntactic and lexical-semantic processing? We addressed these questions in one behavioral and two ERP priming experiments on inflected German adjectives testing a group of advanced late Russian learners of German in comparison to native speaker (L1) controls. While in the behavioral experiment, the L2 learners performed native-like, the ERP data revealed clear L1/L2 differences with respect to the temporal dynamics of grammatical processing. Specifically, our results show that L2 morphosyntactic processing yielded temporally and spatially extended brain responses relative to L1 processing, indicating that grammatical processing of inflected words in an L2 is more demanding and less automatic than in the L1. However, this group of advanced L2 learners showed native-like lexical-semantic processing.