Research

  • The plasticity of lexical selection mechanism in word production: Event-related potential evidence from short-term language switching training in unbalanced Chinese-English bilinguals
    Chunyan Kang, Fengyang Ma, and Taomei Guo

    Abstract: 
    The present study examined the plasticity of the lexical selection mechanism in bilingual word production by training a group of unbalanced Chinese-English bilinguals with a language switching task. The experimental group received an 8-day language switching training, while the control group received no training. Before and after training, the behavioral and event-related potential (ERP) data of both groups in a cued picture naming task were collected. ERP results revealed a training effect such that after training, the N2 peak latency in cue-locked ERPs was shortened only in the experimental group. These results suggest that short-term language switching experience could improve the efficiency to establish the target language task schema, and that the language control mechanism of word production in unbalanced bilinguals could be modulated by language switching experience.

This project has been published:

Kang, Ch., Ma, F., & Guo, T. (2017). Bilingualism: Language and Cognition, 19, 1-18.

  • When late second language learners access the meaning of L2 words: Using ERPs to investigate the role of the L1 translation equivalent
    Fengyang Ma, Peiyao Chen, Taomei Guo, and Judith F. Kroll

Abstract: According to the Revised Hierarchical Model (Kroll & Stewart, 1994), second language (L2) learners initially access the meaning of L2 words via the L1 whereas advanced learners access meaning directly. We tested this hypothesis with English learners of Spanish in a translation recognition task, in which participants were asked to judge whether English words were the correct translations of Spanish words. We gathered data on behavior and on the earliest time course of processing using ERPs. The critical conditions compared the performance of learners to reject distractors that were related to the translation in form or meaning when a long (750 ms) or short (300 ms) SOA separated the two words. The behavioral data revealed semantic and translation interference at both SOAs. The ERP data showed that at the long SOA, a larger P200, a smaller N400, and a larger LPC were elicited by semantic distractors. In addition, a larger P200 and a larger LPC were elicited by form distractors. At the short SOA, only a smaller N400 for semantic distractors was revealed. These results are remarkably similar to the pattern reported by Guo, Misra, Tam, and Kroll (2012) for relatively proficient Chinese-English bilinguals. Overall, these data suggest that even less proficient learners are able to access the meaning of the L2 word in comprehension without L1 mediation.

This project has been published:

Ma, F., Chen, P., Guo, T., & Kroll, J. F. (2017). When late second language learners access the meaning of L2 words: Using ERPs to investigate the role of the L1 translation equivalent. .Journal of Neurolinguistics, 41(1), 50-69.

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  • Reactive and proactive control in bilingual word production: An investigation of influential factors
    Fengyang Ma
    , Shengcao Li, Taomei Guo

Abstract: The present study examined how reactive control (indexed by switching costs) and proactive control (indexed by mixing costs) during bilingual language production was modulated by three factors reflected by different time-courses of stimulus presentation. In three experiments, unbalanced Chinese–English bilinguals named digits in Chinese orEnglish according to a naming cue. In Experiment 1, switching costs reduced when participants had longer preparation time to select the target language to name digits (during the Cue-Stimulus interval, CSI), indicating that longer preparation time helps overcome reactive inhibition. In addition, mixing costs declined drastically at a longer preparation time, indicating that a tiny amount of preparation time allows bilinguals to overcome costs associated with proactively preparing two languages. In Experiment 2, the stimuli were presented prior to the cues, so that participants were given different amounts of time to activate the target lexical nodes in both languages before they were informed of the naming language (during the Stimulus-Cue interval, SCI). Symmetrical switching and mixing costs were observed, indicating that bilinguals can strategically boost activation of the target lexical item in the second language (L2) and attempt to equalize it with its translation equivalent in the native language (L1), when they know previously the specific lexical items to be prepared in two languages. In Experiment 3, different Response-Cue intervals (RCIs) were provided after participants named a digit. It was found that the switching cost asymmetry was more prominent when the time to resolve competition was shorter, while the mixing cost asymmetry emerged only with the longest waiting time. These findings provide the first piece of evidence for the dissipation of the reactive inhibition over time, and suggest that longer preparation would allow the proactive control mechanism to be sensitive the relative proficiency levels of the two languages, leading to stronger proactive control on the dominant language. Taken together, the findings in the present study suggest the dynamic nature of reactive and proactive control in unbalanced bilinguals and have important implications for the current models of bilingual language production, which do not explicitly distinguish the two types of control or address how they adapt to the fine-grained time course of the situation.

This project has been published:

Ma, F., Li, Sh., & Guo, T. (2016). Reactive and proactive control in bilingual word production: An investigation of influential factors. Journal of Memory and Language, 86, 35-59.

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  • Improving proactive control with training on language switching in bilinguals
    Haoyun Zhang, Chunyan Kang, Yanjing Wu, Fengyang Ma, Taomei Guo.

Abstract: The present study examined how a short period of language switching training affects nonverbal cognitive control, as measured by the AX version of the Continuous Performance Test. A group of ChineseEnglish bilinguals were trained over 10 days on a picture naming task that required switching between languages. We recorded their behavioral performance and event-related potentials before and after the training to examine its effects on cognitive performance. The behavioral measurement of proactive control, that is, goal maintenance before the occurrence of the target, is significantly larger in the post-training phase as compared with the pretraining phase, indicating a proactive control shift. The event-related potential results show that the training led to an increase in the mean amplitude of the N2 component, elicited by both the cue and the probe stimuli. A group of control participants who did not undergo training showed an enlarged N2 only for the probe but not for the cue stimuli in the second as compared with the first phase of testing. No variations in behavioral performance were found in the control group between the two phases of testing. These findings suggest that language switching training enhances proactive control in bilinguals.

This project has been published:

Zhang, H., Kang, Ch., Wu, Y., Ma, F., & Guo, T. (2015). Improving proactive control with training on language switching in bilinguals. NeuroReport, 26(6), 354-359.

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  • An ERP study of inhibition of non-target languages in trilingual word production
    Taomei Guo, Fengyang Ma, Fengqin Liu

Abstract: The present study examined the locus where inhibition of non-target languages is exerted during trilingual word production by analyzing the cue-locked and stimulus-locked ERPs respectively in the n-2 language repetition paradigm. During the experiment, Uighur–Chinese–English trilinguals overtly named Arabic digits in one of their three languages according to a visually presented cue while their behavioral and electrophysiological responses were recorded. The behavioral data revealed insignificant n-2 repetition costs. Cue-locked ERPs revealed also only tiny or marginally significant n-2 repetition effects over some midline electrodes. The stimulus-locked ERP data showed a more negative ERP component elicited by the n-2 repetition trials than the n-2 non-repetition trials around 250 ms after stimulus onset, but no significant difference in this ERP effect between different languages was found. The results indicate that inhibition of non-target languages occurs at the lemma selection phase rather than the language task schemas phase during trilingual language production.

This project has been published:

Guo, T., Ma, F., & Liu, F. (2013). An ERP study of inhibition of non-target languages in trilingual word production. Brain and Language, 127(1), 12-20.