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Dual/multiple language use has been shown to affect cognition and its neural substrate, although the replicability of such findings varies, partially due to neglecting the role of interindividual variability in bilingual experience. To address this, we operationalized the main bilingual experience factors as continuous variables, investigating their effects on executive control performance and neural substrate deploying a Flanker task and structural magnetic resonance imaging. First, higher L2 proficiency predicted better executive performance. Second, neuroimaging results indicated that bilingualism-related neuroplasticity may peak at a certain stage of bilingual experience and eventually revert, possibly following functional specialization. Importantly, experienced bilinguals optimized behavioral performance independently of volumetric variations, suggesting a degree of performance gain even with lower GMV. Hence, the effects of bilingualism on cognition may evolve with experience, with improvements in functional efficiency eventually replacing structural changes. We conclude that individual differences in bilingual experience modulate cognitive and neural consequences of bilingualism. [ABSTRACT FROM AUTHOR]

We investigated effects of crosslinguistic phonological and semantic similarity on the bilingual lexicon of late unbalanced bilinguals. Our masked priming paradigm used L1 (Russian) words as masked primes and L2 (English) words as targets. The primes and the targets either overlapped – phonologically, semantically, both phonologically and semantically – or did not overlap. Participants maintained the targets in memory and matched them against occasionally presented catch stimuli. N170 and N400 components of the word-elicited high-density ERPs were identified and analysed in signal and source space. Crosslinguistic semantic similarity shortened the reaction times. The semantics-related N400 amplitude difference correlated with individual L2 proficiency, while phonological similarity suppressed the N400 amplitude in the semantically unrelated condition. ERP source analysis suggests that these ERP dynamics are underpinned by cortical generators in the left IFG and the temporal pole. We conclude that the semantic and phonological interplay between L1 and L2 suggest an integrated bilingual lexicon. [ABSTRACT FROM AUTHOR]

The processing of causal relations has been constantly found to be asymmetrical once the roles of cause and effect are assigned to objects in interactions. We used a relationship recognition paradigm and recorded electroencephalographic (EEG) signals to explore the neural mechanism underlying the asymmetrical representations of causal relations in semantic memory. The results revealed that the verification of causal relations is faster if two words appear in "cause-effect" order (e.g., virus-epidemic) than if they appear in "effect-cause" order (e.g., epidemic-virus), whereas no such asymmetrical representation was found for the verification of hierarchical relations with reverse orders (e.g., bird-sparrow vs. sparrow-bird) in Experiment 1. Furthermore, the P2 amplitude elicited by "superordinate-subordinate" order was larger than that when in reverse order, whereas the N400 effect elicited by "cause-effect" order was smaller (more positive) than when in reverse order. However, no such asymmetry, as well as P2 and N400 components, were observed when verifying the existence of a general associative relation in Experiment 2.We suggested that the smaller N400 in cause-effect order indicates their increased salience in semantic memory relative to the effect-cause order. These results provide evidence for dissociable neural processes, which are related to role binding, contributing to the generation of causal asymmetry. [ABSTRACT FROM AUTHOR]

The extraction of task-related single trial ERP features has recently gained much interest, in particular in simultaneous EEG-fMRI applications. In this study, a specific decomposition known as parallel factor analysis ( PARAFAC) was used, in order to retrieve the task-related activity from the raw signals. Using visual detection task data, acquired in normal circumstances and simultaneously with fMRI, differences between distinct task-related conditions can be captured in the trial signatures of specific PARAFAC components when applied to ERP data arranged in Channels × Time × Trials arrays, but the signatures did not correlate with the fMRI data. Despite the need for parameter tuning and careful preprocessing, the approach is shown to be successful, especially when prior knowledge about the expected ERPs is incorporated. [ABSTRACT FROM AUTHOR]

Much publicity has been given to the fact that people's economic decisions often deviate from the rational predictions of standard economic models. In the classic ultimatum game, for example, most people turn down financial gains by rejecting unequal monetary splits. The present study points to neglected individual differences in this debate. After participants played the ultimatum game we tested for individual differences in cognitive control capacity of the most and least economic responders. The key finding was that people who were higher in cognitive control, as measured by behavioral (Go/No-Go performance) and neural (No-Go N2 amplitude) markers, did tend to behave more in line with the standard models and showed increased acceptance of unequal splits. Hence, the cognitively highest scoring decision-makers were more likely to maximize their monetary payoffs and adhere to the standard economic predictions. Findings question popular claims with respect to the rejection of standard economic models and the irrationality of human economic decision-making. [ABSTRACT FROM AUTHOR]

We investigated the development of early-latency and long-latency brain responses to native and non-native speech to shed light on the neurophysiological underpinnings of perceptual narrowing and early language development. Specifically, we postulated a two-level process to explain the decrease in sensitivity to non-native phonemes toward the end of infancy. Neurons at the earlier stages of the ascending auditory pathway mature rapidly during infancy facilitating the encoding of both native and non-native sounds. This growth enables neurons at the later stages of the auditory pathway to assign phonological status to speech according to the infant's native language environment. To test this hypothesis, we collected early-latency and long-latency neural responses to native and non-native lexical tones from 85 Cantonese-learning children aged between 23 days and 24 months, 16 days. As expected, a broad range of presumably subcortical early-latency neural encoding measures grew rapidly and substantially during the first two years for both native and non-native tones. By contrast, long-latency cortical electrophysiological changes occurred on a much slower scale and showed sensitivity to nativeness at around six months. Our study provided a comprehensive understanding of early language development by revealing the complementary roles of earlier and later stages of speech processing in the developing brain., Competing Interests: Competing Interests: The authors declare competing interests. Patrick C. M. Wong is the founder of a startup company supported by a Hong Kong SAR Government startup scheme for universities., (© 2021 Massachusetts Institute of Technology.)