This study investigates whether late second/foreign language (L2) learners can rely on mechanisms similar to those of native speakers for processing morphologically complex words. Specifically, it examines whether native English speakers who have begun learning French around the onset of puberty can decompose -er (Class I) French verbs. Mid-to-high-proficiency L2 learners and native French speakers completed a masked-priming word-naming task. Latencies for morphologically related, orthographically related, and semantically related prime–target combinations were compared to latencies for identical and unrelated prime–target combinations. The results reveal the following effects: full morphological priming for both native and non-native speakers, with this effect increasing with French proficiency for L2 learners; partial orthographic priming for both groups; greater priming in the morphological condition than in the orthographic condition for both groups; and no semantic priming for either group. We conclude that L2 learners have access to similar mechanisms to those of native speakers for processing morphologically complex words.

The present study examined the influence of phonology on language switching. Unlike previous studies that investigated this influence by comparing words that are phonologically similar vs. dissimilar in two languages, the current language switching study focused on the role of phonological characteristics across words. Specifically, words with the first two phonemes being identical to those of the word in the previous trial were contrasted against words without such phonological overlap. The results revealed that the switch cost asymmetry was influenced by phonological overlap. Further investigation revealed that this influence was mainly due to persisting after-effects of phonological overlap, which caused a reversal of the asymmetrical switch cost pattern in the following trial. These results clearly indicate that manipulations on the level of phonology can have an effect on language switching. Therefore, we propose that, in contrast with the claims of most models, phonological characteristics of words play an important role in language control.

The study of bilingualism has generated great interest about a core issue: does the experience of using two or more languages lead to enduring changes in the bilingual brain. This issue is often framed as a search for bilingual advantages in cognition, most notably behavioral performance on executive control tasks. Valian's timely keynote (2014) adopts this framing.

Masked priming research with late (non-native) bilinguals has reported facilitation effects following morphologically derived prime words (scanner – scan). However, unlike for native speakers, there are suggestions that purely orthographic prime-target overlap (scandal – scan) also produces priming in non-native visual word recognition. Our study directly compares orthographically related and derived prime-target pairs. While native readers showed morphological but not formal overlap priming, the two prime types yielded the same magnitudes of facilitation for non-natives. We argue that early word recognition processes in a non-native language are more influenced by surface-form properties than in one's native language.

This study examined behavioral and neurophysiological indices of discrimination of an English vowel contrast [ɪ–ɛ] by early and late bilingual Spanish–English speakers, compared to monolingual English speakers. Electrophysiological measures (Mismatched Negativity – MMN) and behavioral measures (AX discrimination and forced-choice identification) were employed to examine perception of a nine-step vowel continuum, re-synthesized from natural tokens. Results revealed that (i) both monolingual and early bilinguals showed similar behavioral perception while late bilinguals performed more poorly on all behavioral tasks; and (ii) monolinguals showed robust evidence of discrimination (MMN) at a pre-attentive level that was significantly larger than found for either early or late bilinguals. These findings suggested that early input of English vowels to bilinguals did not necessarily lead to robust, automatic processing, as measured at a more attention-independent neural level; but earlier experience with a second language allowed for native-like speech perception measured with behavioral tasks.

This study investigated the referring expressions used for first mentions of participants and entities in narratives by Mandarin heritage language (HL) and monolingual children. Referring expressions for first mentions in Mandarin comprise lexical, morphological and syntactic devices. Results showed that HL children used less adequate referring expressions for first mentions than the monolinguals, mainly due to overgeneralization of classifiers and lack of vocabulary knowledge. However, HL children did not differ from monolinguals in their use of relative clauses and post-verbal NP placement to mark first mentions. These results suggest that incomplete acquisition of the HL may vary across different linguistic subdomains (Montrul, 2008); specifically, domains requiring a great deal of input to acquire, such as vocabulary and the large repertoire of classifier morphemes, might be more vulnerable in HL speakers than syntax. Mixed modeling analyses revealed that older age of arrival, higher maternal education levels and a rich and diverse Mandarin environment at home predicted stronger narrative outcomes, also pointing to an important role for input in HL acquisition.

We applaud Valian's (2014) thoughtful analysis of the cross-sectional and longitudinal studies that have thus far contributed to our knowledge about the role of bilingualism in cognitive aging. In evaluating the literature as summarized by Valian, we think it is useful to distinguish between the following four research questions and representative analytic approaches: (1) cross-sectional associations between bilingualism and executive function (e.g., regression), (2) longitudinal associations between bilingualism and change in executive function (e.g., growth curve modeling), (3) bilingualism as a predictor of dementia incidence (e.g., time-to-event analysis), and (4) bilingualism as a source of cognitive reserve (e.g., comparisons of brain pathology between bilinguals and monolinguals matched on cognitive performance).

The current study examined the influence of phonological structure and language experience on the nonword repetition performance of bilingual children. Twenty-six Spanish-dominant and 26 English-dominant Spanish–English bilingual five-year-old children were matched on current exposure to the dominant language and year of first exposure to English. Participants repeated non-wordlike nonwords in English and Spanish. The Spanish-dominant group performed better than the English-dominant group for both Spanish and English nonwords. In addition, there was a main effect for test language, where Spanish nonwords were produced more accurately than English nonwords overall. The Spanish-dominant group advantage for nonwords is interpreted as emerging from the extra practice the dominant Spanish speakers had producing multisyllabic words.

This study examined the production of the Dutch past tense in Dutch–Hebrew bilingual children and investigated the effect of type of past tense allomorph (de versus te) and token frequency on productions of the past tense. Seven-year-old bilingual children (n=11) were compared with monolingual children: age-matched (n=30) and younger vocabulary-matched (n=21). Accuracy of regular and novel past tense was similar for the bilingual and monolingual groups, but the former group was worse on irregular past tense than the age-matched monolingual peers. All three groups showed effects of type frequency: te past tenses were more accurate than de. The difference between the bilingual and monolingual children surfaces in the extent of the effect: for the bilingual children it was most pronounced in verbs with low token frequency and novel verbs. Results are interpreted as stemming from a learning strategy or from phonological transfer from the Hebrew morphosyntactic system.

The goal of my keynote article, “Bilingualism and Cognition” (Valian, 2014), was to resolve the inconsistencies in effects of bilingualism on executive functions, whether the individuals were children, young adults, or old people. To summarize (and sharpen) my argument:

1. 1. Especially in children and young adults, benefits of bilingualism for executive functions are not reliable. In old people, there are benefits for executive functions but contradictory results on delay of cognitive impairment, depending on whether studies are retrospective or prospective.

2. 2. All experiences that have benefits for executive functions and aging – and there are many – yield inconsistent effects. Bilingualism is not alone.

3. 3. Three reasons for inconsistencies in bilingualism and other experiences are:

   1. a. Executive function and cognitive reserve are broad cover terms for a variety of mechanisms, most of which are ill-understood. Because we mean different things by ‘executive function’ from one experiment to the next, we can both think we don't have an effect when we do and think we have an effect when we don’t.

   2. b. Tasks are impure: apparently similar tasks measure different aspects of executive function and measure other aspects of cognition as well. Because we lack a good analysis of tasks, we too often do not know what we are measuring. I encourage readers to examine the demos in the supplementary materials of the keynote article to see for themselves what the tasks are like.

   3. c. Individuals engage in many different activities that may be on a par with bilingualism in their benefits.

4. 4. Different types of bilingual experience are unlikely to explain the variability of findings, given the inconsistencies in extant data on varieties of bilingualism.

5. 5. There is a benefit of bilingualism, but bilingualism competes with other sources of benefits. Especially for children and young adults, whose daily lives are full of cognitively enriching and challenging experiences, we should expect variability in effects of being bilingual.

6. 6. The way forward is to focus on underlying mechanisms.

Previous research suggests that the way grammatical aspect is encoded in the speaker's L1 influences event conceptualisation and its subprocesses even in highly advanced L2. Given the lack of consensus regarding the susceptibility to restructuring L1 principles in L2, this work contributes to the debate with two innovative components: it tests whether the susceptibility to adjust L1 (Czech and Hungarian) structuring principles in L2 (English) is dependent on a specific degree of L1-L2 overlap in aspect marking, and it examines unique learner-specific structuring techniques that surface in picture descriptions and film retellings, to illustrate how bilinguals’ temporal reference frames converge. Besides signalling the construction of a unitary conceptual frame, L2 results clearly show the importance of language distance for explaining the nature of sequential bilinguals’ temporal structuring. To embrace the implications of the reported phenomenon, a novel proposal is developed, incorporating grammatical knowledge types already at the stage of conceptualisation.

Previous research showing a bilingual advantage on a variety of executive control tasks has typically compared monolinguals and fluent bilinguals. No study to date, however, has examined whether these effects endure for bilingual individuals who revert to monolingualism (‘lapsed bilinguals’). We investigated this question by testing monolinguals, full bilinguals, and lapsed bilinguals on a flanker task and a working memory task. Fully fluent bilinguals exhibited significantly more accurate performance than monolinguals on the working memory task, with lapsed bilinguals performing between the other two groups. Thus, continued bilingual experience appears necessary to maintain these cognitive advantages at a high level.

Hearing children of Deaf parents simultaneously acquire sign language and spoken language, which have many structural differences and represent two different modalities. We video-recorded eight children every six months between the ages of 12 and 24 months during three different play sessions: with their Deaf parent, with the Deaf parent and a hearing adult, and with a hearing adult alone. Additionally, we collected data on their vocabulary development in both sign language and spoken language. Children as young as 12 months old accommodated their language use according to the language(s) of their interlocutor(s). Additionally, the children used a manual modality that included gestures more frequently and in a more diverse way when interacting with their Deaf parent than with a hearing person. These findings bring new knowledge about language differentiation and gesture use of bilingual children during the early phases of language acquisition.

Language switching was studied with older adult (age 65 years and older) and young adult (18–24 years) bilinguals in a blocked-language or mixed-language condition. Results revealed small differences in reaction time (RT) between older adults and college-age participants in the blocked condition. However, older adults showed much slower RTs in the mixed condition which involves sustained switching relative to young adults. In Experiment 2, the same design was used except that participants were asked to translate an auditory word. In this condition, older adults showed a slowing effect but to a much lesser degree. Furthermore, comparisons within the mixed condition (transient switching) revealed that switching costs varied across languages and age groups. The results from the picture-naming task are consistent with models that predict deficiencies in task-set shifting in older adults especially when a stimulus activates multiple responses. Furthermore, the results indicate interesting differences in sustained and transient switching depending on the task.

This study analyzes gender assignment in Spanish–Basque mixed nominal constructions with nouns in Basque (a language that lacks gender) and determiners in Spanish (a language that marks gender) by using a multi-task approach: (i) naturalistic data, (ii) an elicitation task, and (iii) an auditory judgment task. Naturalistic data suggest cross-language effects under which a morphological marker of Basque (-a determiner) is interpreted as a morphophonological expression of gender marking in Spanish. A preference for feminine determiners was observed in the judgment task, which differs from the masculine default trend observed in Spanish–English bilinguals (Jake, Myers-Scotton & Gross, 2002). Our results point to feminine gender as default in Spanish–Basque mixed DPs, indicating that the resources that bilinguals use for gender assignment can be different from those of monolinguals. We argue that this is an outcome of interacting processes which take place at the interfaces (lexicon, phonology, morphosyntax) of both languages, resulting in cross-language effects.

Recent findings suggested that an L2-immersion school experience produced some of the cognitive benefits associated with early bilingualism. However, the cognitive differences observed might possibly be due to greater cognitive development in the immersion group before the children started the immersion program. The present study thus aimed at revisiting these results in a follow-up design in which children about to begin an L2-immersion program and monolinguals were matched for cognitive development. Our results support the previous findings and this longitudinal study strongly confirms that only 3 years in an L2-immersion program enhance the performance of the attentional/executive control network.

The current study investigated the effects of bilingualism on the clinical manifestation of Alzheimer's disease (AD) in a European sample of patients. We assessed all incoming AD patients in two university hospitals within a specified timeframe. Sixty-nine monolinguals and 65 bilinguals diagnosed with probable AD were compared for time of clinical AD manifestation and diagnosis. The influence of other potentially interacting variables was also examined. Results indicated a significant delay for bilinguals of 4.6 years in manifestation and 4.8 years in diagnosis. Our study therefore strengthens the claim that bilingualism contributes to cognitive reserve and postpones the symptoms of dementia.

The role of age of acquisition (AoA) in reaching native-like proficiency in second language is controversial. The existence of a critical period and the effect of AoA have been questioned by studies testing lexical and/or morphosyntactic skills, and by functional brain exploration. The aim of this study was to verify the effect of AoA and language practice on proficiency in a bilingual pragmatic task and its relationship with cognitive skills. The study involved a group of Italian–Spanish bilinguals, classified according to their AoA and language use. All participants performed a pragmatic bilingual test and a battery of cognitive tests. A multivariate analysis showed significant effects of language use and cognitive skills and a non-significant effect of AoA. These results indicate that continued language practice is a major factor influencing high bilingual proficiency, irrespective of AoA, suggesting that proficiency may be weakened when bilingual experience becomes occasional or ceases.

The aim of the present study is two-fold. First, we investigate age-related changes to bilingual language control (bLC) mechanisms across lifespan. Second, we explore the relation between bLC mechanisms and those of the domain-general executive (EC) system by looking at age effects on these two systems. To do so, we compare the performances of the three age groups of bilinguals (young, middle-aged and elderly) in a language switching task to those of non-linguistic switching task. We found an age-related change in the non-linguistic switch cost but not in the language switch cost. Moreover, we did not find any correlation between the magnitudes of the switch costs. Taken together these results indicate that bLC is not affected by age as the EC system is, and interestingly, we add new evidence that the bLC mechanisms are not fully subsidiary to those of the domain-general EC system.