Clitic pronouns reveal the time course of processing gender and number in a second language

The Critical Period Hypothesis for L2 Acquisition: An Unfalsifiable Embarrassment?

This article focuses on the uncertainty surrounding the issue of the Critical Period Hypothesis. It puts forward the case that, with regard to naturalistic situations, the hypothesis has the status of both “not proven” and unfalsified. The article analyzes a number of reasons for this situation, including the effects of multi-competence, which remove any possibility that competence in more than one language can ever be identical to monolingual competence. With regard to the formal instructional setting, it points to many decades of research showing that, as critical period advocates acknowledge, in a normal schooling situation, adolescent beginners in the long run do as well as younger beginners. The article laments the profusion of definitions of what the critical period for language actually is and the generally piecemeal nature of research into this important area. In particular, it calls for a fuller integration of recent neurolinguistic perspectives into discussion of the age factor in second language acquisition research.

Cognitive Control Facilitates Attentional Disengagement during Second Language Comprehension

Bilinguals learn to resolve conflict between their two languages and that skill has been hypothesized to create long-term adaptive changes in cognitive functioning. Yet, little is known about how bilinguals recruit cognitive control to enable efficient use of one of their languages, especially in the less skilled and more effortful second language (L2). Here we examined how real-time cognitive control engagement influences L2 sentence comprehension (i.e., conflict adaptation). We tested a group of English monolinguals and a group of L2 English speakers using a recently-developed cross-task adaptation paradigm. Stroop sequences were pseudo-randomly interleaved with a visual-world paradigm in which participants were asked to carry out spoken instructions that were either syntactically ambiguous or unambiguous. Consistent with previous research, eye-movement results showed that Stroop-related conflict improved the ability to engage correct-goal interpretations, and disengage incorrect-goal interpretations, during ambiguous instructions. Such cognitive-to-language modulations were similar in both groups, but only in the engagement piece. In the disengagement portion, the modulation emerged earlier in bilinguals than in monolinguals, suggesting group differences in attentional disengagement following cognitive control recruitment. Additionally, incorrect-goal eye-movements were modulated by individual differences in working memory, although differently for each group, suggesting an involvement of both language-specific and domain-general resources.

Using event-related potentials to track morphosyntactic development in second language learners: The processing of number and gender agreement in Spanish

We used event-related potentials to investigate morphosyntactic development in 78 adult English-speaking learners of Spanish as a second language (L2) across the proficiency spectrum. We examined how development is modulated by the similarity between the native language (L1) and the L2, by comparing number (a feature present in English) and gender agreement (novel feature). We also investigated how development is impacted by structural distance, manipulating the distance between the agreeing elements by probing both within-phrase (fruta muy jugosa "fruit-FEM-SG very juicy-FEM-SG") and across-phrase agreement (fresa es ácida "strawberry-FEM-SG is tart-FEM-SG"). Regression analyses revealed that the learners' overall proficiency, as measured by a standardized test, predicted their accuracy with the target properties in the grammaticality judgment task (GJT), but did not predict P600 magnitude to the violations. However, a relationship emerged between immersion in Spanish-speaking countries and P600 magnitude for gender. Our results also revealed a correlation between accuracy in the GJT and P600 magnitude, suggesting that behavioral sensitivity to the target property predicts neurophysiological sensitivity. Subsequent group analyses revealed that the highest-proficiency learners showed equally robust P600 effects for number and gender. This group also elicited more positive waveforms for within- than across-phrase agreement overall, similar to the native controls. The lowest-proficiency learners showed a P600 for number overall, but no effects for gender. Unlike the highest-proficiency learners, they also showed no sensitivity to structural distance, suggesting that sensitivity to such linguistic factors develops over time. Overall, these results suggest an important role for proficiency in morphosyntactic development, although differences emerged between behavioral and electrophysiological measures. While L2 proficiency predicted behavioral sensitivity to agreement, development with respect to the neurocognitive mechanisms recruited in processing only emerged when comparing the two extremes of the proficiency spectrum. Importantly, while both L1-L2 similarity and hierarchical structure impact development, they do not constrain it.

Direct object pronoun sentence processing in Spanish-English children with/without Specific Language Impairment and adults: A cross-modal priming study

PURPOSE

This paper examines whether bilingual children with Specific Language Impairment (SLI) showed limited comprehension of Direct Object (DO) pronoun sentences and/or morphosyntactic priming compared to children with Typical Language Development (TLD) and adults. We analyzed the relation of these morphosyntactic processes to other psycholinguistic abilities, according to the MUC (Memory-Unification-Control) model.

METHOD

Ten bilingual native Spanish-speaking children with SLI (8;3-10;6) and 10 age-matched children with TLD (7;6-10;10) received a psycholinguistic evaluation in Spanish-English. The 20 children and 10 adults (19-34) performed an on-line cross-modal pronoun task. They listened to long distance animate DO pronoun sentences, and filler sentences without any pronoun. At the offset of the pronoun in each pronoun sentence, a picture of an animal for the antecedent (match condition), another animal for the second noun (mismatch), or an unrelated object (neutral) was displayed on the screen. In the filler sentences, a picture of an object that depicted the first noun, appeared at the offset of another later noun. Participants decided whether that pictured item was "alive"/"not alive" by pressing two keys on the computer keyboard. Immediately after, they answered an oral comprehension question about the DO pronoun sentence.

RESULTS

Bilingual children with SLI showed significantly poorer comprehension of DO pronoun sentences than bilingual children with TLD. Pronoun sentence understanding in the overall children correlated significantly with oral sentence completion, expressive vocabulary abilities, auditory story comprehension, and the non-word repetition task, all in Spanish. Adults showed significantly the highest pronoun sentence comprehension, and the fastest animacy decisions across conditions; it was the only group showing a significant behavioral morphosyntactic priming effect. All groups exhibited high accuracy in the animacy decisions across conditions, although children with SLI showed lower accuracy and more variability.

CONCLUSION

Bilingual Spanish-English children with SLI showed significant limitations in understanding long distance animate DO pronoun sentences. The deficits were also related to weak morphosyntactic, lexical, and/or phonological representations stored in their memory. These processes may be harder to combine in the unification process, and also to control for answering the comprehension questions. Clinical and educational implications are discussed.

Changes in White-Matter Connectivity in Late Second Language Learners: Evidence from Diffusion Tensor Imaging

Morphological brain changes as a consequence of new learning have been widely established. Learning a second language (L2) is one such experience that can lead to rapid structural neural changes. However, still relatively little is known about how levels of proficiency in the L2 and the age at which the L2 is learned influence brain neuroplasticity. The goal of this study is to provide novel evidence for the effect of bilingualism on white matter structure in relatively proficient but late L2 learners who acquired the second language after early childhood. Overall, the results demonstrate a significant effect on white matter fractional anisotropy (FA) as a function of L2 learning. Higher FA values were found in a broad white matter network including the anterior thalamic radiation (ATR), the inferior fronto-occipital fasciculus (IFOF), the Uncinate Fasciculus (UF), and the inferior longitudinal fasciculus (ILF). Moreover, FA values were correlated with age of L2 acquisition, suggesting that learning an L2, even past childhood, induces neural changes. Finally, these results provide some initial evidence that variability in the age of L2 acquisition has important consequences for neural plasticity.

On the Nature of Clitics and Their Sensitivity to Number Attraction Effects

Pronominal dependencies have been shown to be more resilient to attraction effects than subject-verb agreement. We use this phenomenon to investigate whether antecedent-clitic dependencies in Spanish are computed like agreement or like pronominal dependencies. In Experiment 1, an acceptability judgment self-paced reading task was used. Accuracy data yielded reliable attraction effects in both grammatical and ungrammatical sentences, only in singular (but not plural) clitics. Reading times did not show reliable attraction effects. In Experiment 2, we measured electrophysiological responses to violations, which elicited a biphasic frontal negativity-P600 pattern. Number attraction modulated the frontal negativity but not the amplitude of the P600 component. This differs from ERP findings on subject-verb agreement, since when the baseline matching condition obtained a biphasic pattern, attraction effects only modulated the P600, not the preceding negativity. We argue that these findings support cue-retrieval accounts of dependency resolution and further suggest that the sensitivity to attraction effects shown by clitics resembles more the computation of pronominal dependencies than that of agreement.

Late Bilinguals Are Sensitive to Unique Aspects of Second Language Processing: Evidence from Clitic Pronouns Word-Order

In two self-paced reading experiments we asked whether late, highly proficient, English-Spanish bilinguals are able to process language-specific morpho-syntactic information in their second language (L2). The processing of Spanish clitic pronouns' word order was tested in two sentential constructions. Experiment 1 showed that English-Spanish bilinguals performed similarly to Spanish-English bilinguals and revealed sensitivity to word order violations for a grammatical structure unique to the L2. Experiment 2 replicated the pattern observed for native speakers in Experiment 1 with a group of monolingual Spanish speakers, demonstrating the stability of processing clitic pronouns in the native language. Taken together, the results show that late bilinguals can process aspects of grammar that are encoded in L2-specific linguistic constructions even when the structure is relatively subtle and not affected for native speakers by the presence of a second language.