When Native Speakers Are Not "Native-Like:" Chunking Ability Predicts (Lack of) Sensitivity to Gender Agreement During Online Processing.

Previous work on individual differences has revealed limitations in the ability of existing measures (e.g., working memory) to predict language processing. Recent evidence suggests that an individual's sensitivity to detect the statistical regularities present in language (i.e., "chunk sensitivity") may significantly modulate online sentence processing. We investigated whether individual chunk sensitivity predicted the online processing of gender cues, a core linguistic feature of Spanish. In a self-paced reading task, we examined native speakers' processing of relative clauses in which gender cues were variably exploited to induce processing costs. Even after considering the effect of working memory and cognitive control, the results revealed a significant effect of chunking ability in modulating online sentence processing. Critically, higher-chunking ability speakers' reading times showed online sensitivity to core linguistic cues online; while low-chunking ability readers showed no sensitivity to manipulations, indicating shallow real-time processing of their native language.

Native language inhibition predicts more successful second language learning: Evidence of two ERP pathways during learning.

How some individuals succeed in learning a second language as adults is still an unsolved question in cognitive neuroscience. At the brain level, adults' electrophysiological responses to input in a second language may differ after completing different types of training. However, there is limited understanding of what neural pathways are activated as learning unfolds, and which patterns of activation lead to successful learning. Using brain event-related potentials, this study explored whether individual brain responses to practice difficulty during second language learning predict learning outcomes. English-speaking learners of Spanish practiced completing newly learned phrases in their second language. For some learners, all the choices presented during practice were "easy" because non-target choices were unrelated distractors. In the more "difficult" practice mode, however, learners had to avoid choosing a competing word that would be acceptable based on their native language, but not in the second language being learned. Performance during practice was similar in both groups of learners. Critically, divergence in event-related potentials indicated alternative strategies to practice, based on the level of difficulty. At the group level, learners completing the easier practice revealed increased monitoring when making responses; in the difficult condition, learners showed inhibition of their native language (i.e., an N400 for phrases congruent with the native language) to avoid interference during word selection. Individual brain responses indexing the degree of native language inhibition predicted learning rates in tests.

Individual Chunking Ability Predicts Efficient or Shallow L2 Processing: Eye-Tracking Evidence From Multiword Units in Relative Clauses.

Behavioral studies on language processing rely on the eye-mind assumption, which states that the time spent looking at text is an index of the time spent processing it. In most cases, relatively shorter reading times are interpreted as evidence of greater processing efficiency. However, previous evidence from L2 research indicates that non-native participants who present fast reading times are not always more efficient readers, but rather shallow parsers. Because earlier studies did not identify a reliable predictor of variability in L2 processing, such uncertainty around the interpretation of reading times introduces a potential confound that undermines the credibility and the conclusions of online measures of processing. The present study proposes that a recently developed modulator of online processing efficiency, namely, chunking ability, may account for the observed variability in L2 online reading performance. L1 English - L2 Spanish learners' eye movements were analyzed during natural reading. Chunking ability was predictive of overall reading speed. Target relative clauses contained L2 Verb-Noun multiword units, which were manipulated with regards to their L1-L2 congruency. The results indicated that processing of the L1-L2 incongruent units was modulated by an interaction of L2 chunking ability and level of knowledge of multiword units. Critically, the data revealed an inverse U-shaped pattern, with faster reading times in both learners with the highest and the lowest chunking ability scores, suggesting fast integration in the former, and lack of integration in the latter. Additionally, the presence of significant differences between conditions was correlated with individual chunking ability. The findings point at chunking ability as a significant modulator of general L2 processing efficiency, and of cross-language differences in particular, and add clarity to the interpretation of variability in the online reading performance of non-native speakers.

The Neural Correlates of Conflict Detection and Resolution During Multiword Lexical Selection: Evidence from Bilinguals and Monolinguals.

Previous studies have identified the Event Related Potential (ERP) components of conflict detection and resolution mechanisms in tasks requiring lexical selection at the individual word level. We investigated the brain potentials associated with these mechanisms in a lexical selection task based on multiword units made up of verb-noun combinations (e.g., eat breakfast, skip school). Native and non-native English speakers were asked to select a familiarized target verb-noun sequence (eat breakfast) between two choices. Trials were low-conflict, with only one plausible candidate (e.g., eat - shoot - breakfast) or high-conflict, with two plausible verbs (e.g., eat - skip - breakfast). Following the presentation of the noun, native English speakers showed a biphasic process of selection, with a conflict-detection centro-parietal negativity between 500 and 600 ms (Ninc), followed by a right frontal effect (RFE) between 600 and 800 ms preceding responses. Late Spanish-English bilinguals showed a similar but more sustained and more widespread effect. Additionally, brain activity was only significantly correlated with performance in native speakers. Results suggest largely similar basic mechanisms, but also that different resources and strategies are engaged by non-native speakers when resolving conflict in the weaker language, with a greater focus on individual words than on multiword units.