Oscillatory brain responses to processing code-switches in the presence of others.

Code-switching, i.e. the alternation between languages in a conversation, is a typical, yet socially-constrained practice in bilingual communities. For instance, code-switching is permissible only when other conversation partners are fluent in both languages. Studying code-switching provides insight in the cognitive and neural mechanisms underlying language control, and their modulation by linguistic and non-linguistic factors. Using time-frequency representations, we analyzed brain oscillation changes in EEG data recorded in a prior study (Kaan et al., 2020). In this study, Spanish-English bilinguals read sentences with and without switches in the presence of a bilingual or monolingual partner. Consistent with prior studies, code-switches were associated with a power decrease in the lower beta band (15-18 Hz). In addition, code-switches were associated with a power decrease in the upper gamma band (40-50 Hz), but only when a bilingual partner was present, suggesting the semantic/pragmatic processing of code-switches differs depending on who is present.

Access to verb bias and plausibility information during syntactic processing in adult Spanish-English bilinguals.

In two experiments, we examine how proficient second language speakers integrate verb bias and plausibility information during online sentence comprehension. Spanish-English speakers and native English speakers read sentences in English in which a post-verbal noun phrase (NP) could be interpreted as a direct object or a sentential subject. To examine the role of verb bias, the post-verbal NP was preceded by a verb that is preferentially followed by a direct object (DO-bias verbs) or a sentential complement (SC-bias verbs). To assess the role of plausibility, the semantic fit between the verb and the post-verbal NP was either congruent or incongruent with the direct object interpretation. The results show that both second language speakers and native speakers used verb bias information to assign a grammatical role to the post-verbal ambiguous NP with small differences. Syntactic revision of an initially incorrect DO interpretation was facilitated by the presence of an implausible NP.

Understanding counterfactuals in transparent and nontransparent context: An event-related potential investigation.

Counterfactuals describe imagined alternatives to reality that people know to be false. Successful counterfactual comprehension therefore requires people to keep in mind both an imagined hypothetical world and the presupposed real world. Counterfactual transparency, that is, the degree to which a context makes it easy to determine counterfactuality, might affect semantic processing. This might especially be the case for languages like Chinese which lack dedicated counterfactual markers and therefore are more context-dependent. Using event-related potentials, this study investigates the role of counterfactual transparency on the comprehension of Chinese counterfactuals. For transparent contexts (e.g., "If everything in the world could go back in time . . ."), in which the information needed to identify counterfactuality is highly accessible, discourse incongruent words elicited P600 effects. In contrast, for nontransparent contexts (e.g., "If better preparations were made at that time . . .") in which readers must attend to specific discourse context and engage pragmatic information to arrive at the counterfactual interpretation, discourse incongruencies gave rise to N400 effects. These findings suggest that (a) provided a constraining context, semantic processing is not disrupted by the dual nature of counterfactuality (i.e., readers can rapidly make contextually appropriate inferences to interpret subsequent narratives) and (b) the degree of transparency of the counterfactual can affect the nature of subsequent semantic processing. Our findings support the usage-based view that Chinese counterfactual comprehension is highly context-dependent and pragmatics-driven. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Cognitive control in bilinguals: Proficiency and code-switching both matter.

We examined the impact of bilingualism as a construct of both language usage and language proficiency on the effectiveness of cognitive control. In particular, we asked whether the frequency of daily dense code-switching - frequent change of language within and between sentences with the same interlocutor- and the level of L2 proficiency separately and or interactively affect cognitive control efficiency in the Simon task. Results from 134 bilinguals showed that frequently code-switching bilinguals had fewer errors and their accuracy rate improved over trials leading to a smaller Simon effect. For response times (RTs), however, L2 proficiency modulated the Simon effect, and interacted with code-switching frequency in intricate ways in modulating overall RTs over trials. Crucially, highly proficient frequently code-switching bilinguals were better at conflict adaptation. These results show that bilinguals differ among themselves, and that researchers need to take both proficiency and language use into account to test the impact of bilingual experience on cognitive control. Bilingualism should be regarded as a continuum, with many different factors contributing to the language experience and affecting cognitive functioning.

Processing Code-Switches in the Presence of Others: An ERP Study.

Code-switching is highly socially constrained. For instance, code-switching is only felicitous when those present are fluent in both languages. This means that bilinguals need to dynamically adjust their language control and expectation of code-switching to the current social situation or context. The aim of the present EEG study was to investigate how and when language control in the comprehension of code-switches is affected by the assumed language knowledge of others in the context. Spanish-English bilinguals read sentences with and without code-switches together with another Spanish-English bilingual or with an English monolingual. Switches elicited an early fronto-central positivity. This effect was smaller overall when a bilingual was present at the start of the study. In addition, the late positive complex found for switches was smaller when a bilingual was present rather than a monolingual, but only for those participants who were sensitive to the other's language knowledge in their off-line judgments. These findings suggest that the bilinguals in our study expected and activated both languages when initially paired with a bilingual and that they more easily accommodated code-switches, in the presence of a bilingual than in the presence of a monolingual. Our findings support the view that language control can be modulated by the perceived language knowledge of others present, and are compatible with a dynamic control model of bilingual language comprehension.

The sentence wrap-up dogma.

Current sentence processing research has focused on early effects of the on-line incremental processes that are performed at each word or constituent during processing. However, less attention has been devoted to what happens at the end of the clause or sentence. More specifically, over the last decade and a half, a lot of effort has been put into avoiding measuring event-related brain potentials (ERPs) at the final word of a sentence, because of the possible effects of sentence wrap-up. This article reviews the evidence on how and when sentence wrap-up impacts behavioral and ERP results. Even though the end of the sentence is associated with a positive-going ERP wave, thus far this effect has not been associated with any factors hypothesized to affect wrap-up. In addition, ERP responses to violations have not been affected by this positivity. "Sentence-final" negativities reported in the literature are not unique to sentence final positions, nor do they obscure or distort ERP effects associated with linguistic manipulations. Finally, the empirical evidence used to argue that sentence-final ERPs are different from those recorded at sentence-medial positions is weak at most. Measuring ERPs at sentence-final positions is therefore certainly not to be avoided at all costs, especially not in cases where the structure of the language under investigation requires it. More importantly, researchers should follow rigorous method in their experimental design, avoid decision tasks which may induce ERP confounds, and ensure all other possible explanations for results are considered. Although this article is directed at a particular dogma from a particular literature, this review shows that it is important to reassess what is regarded as "general knowledge" from time to time.

Representation and processing of multi-word expressions in the brain.

Language comprehension is sensitive to the predictability of the upcoming information. Prediction allows for smooth, expedient and successful communication. While general discourse-based constraints have been investigated in detail, more specific phrase-level prediction has received little attention. We address this gap by exploring the ERPs elicited during the comprehension of English binomials - familiar and predictable multi-word expressions. In Experiment 1a, participants read binomial expressions (knife and fork), infrequent strongly associated phrases (spoon and fork), and semantic violations (theme and fork). In Experiment 1b, participants read the same stimuli without "and". Experiment 1a revealed that binomials elicited larger P300s and smaller N400s compared to the other conditions, reflecting the activation of a 'template' that matches the upcoming information (P300) and pointing to easier semantic integration (N400). In contrast, no differences were observed between binomials and associates in Experiment 1b. We conclude that distinct mechanisms underlie the processing of predicable and novel sequences.

Processing Code-Switching in Algerian Bilinguals: Effects of Language Use and Semantic Expectancy.

Using a cross-modal naming paradigm this study investigated the effect of sentence constraint and language use on the expectancy of a language switch during listening comprehension. Sixty-five Algerian bilinguals who habitually code-switch between Algerian Arabic and French (AA-FR) but not between Standard Arabic and French (SA-FR) listened to sentence fragments and named a visually presented French target NP out loud. Participants' speech onset times were recorded. The sentence context was either highly semantically constraining toward the French NP or not. The language of the sentence context was either in Algerian Arabic or in Standard Arabic, but the target NP was always in French, thus creating two code-switching contexts: a typical and recurrent code-switching context (AA-FR) and a non-typical code-switching context (SA-FR). Results revealed a semantic constraint effect indicating that the French switches were easier to process in the high compared to the low-constraint context. In addition, the effect size of semantic constraint was significant in the more typical code-switching context (AA-FR) suggesting that language use influences the processing of switching between languages. The effect of semantic constraint was also modulated by code-switching habits and the proficiency of L2 French. Semantic constraint was reduced in bilinguals who frequently code-switch and in bilinguals with high proficiency in French. Results are discussed with regards to the bilingual interactive activation model (Dijkstra and Van Heuven, 2002) and the control process model of code-switching (Green and Wei, 2014).

Effects of production training and perception training on lexical tone perception--A behavioral and ERP study.

The present study recorded both behavioral data and event-related brain potentials to examine the effectiveness of a perception-only training and a perception-plus-production training procedure on the intentional and unintentional perception of lexical tone by native English listeners. In the behavioral task, both the perception-only and the perception-plus-production groups improved on the tone discrimination abilities after the training session. Moreover, the participants in both groups generalized the improvements gained through the trained stimuli to the untrained stimuli. In the ERP task, the Mismatch Negativity was smaller in the post-training task than in the pre-training task. However, the two training groups did not differ in tone processing at the intentional or unintentional level after training. These results suggest that the employment of the motor system does not specifically benefit the tone perceptual skills. Furthermore, the present study investigated whether some tone pairs are more easily confused than others by native English listeners, and whether the order of tone presentation influences non-native tone discrimination. In the behavioral task, Tone2-Tone1 (rising-level) and Tone2-Tone4 (rising-falling) were the most difficult tone pairs, while Tone1-Tone2 and Tone4-Tone2 were the easiest tone pairs, even though they involved the same tone contrasts respectively. In the ERP task, the native English listeners had good discrimination when Tone2 and Tone4 were embedded in strings of Tone1, while poor discrimination when Tone1 was inserted in the context of Tone2 or Tone4. These asymmetries in tone perception might be attributed to the interference of native intonation system and can be altered by training.

ERP Indices of Stimulus Prediction in Letter Sequences.

Given the current focus on anticipation in perception, action and cognition, including language processing, there is a need for a method to tap into predictive processing in situations in which cue and feedback stimuli are not explicitly marked as such. To this aim, event related potentials (ERPs) were obtained while participants viewed alphabetic letter sequences ("A", "B", "C", "D", "E", …), in which the letters were highly predictable, and random sequences ("S", "B", "A", "I", "F", "M", …), without feedback. Occasionally, the presentation of a letter in a sequence was delayed by 300 ms. During this delay period, an increased negativity was observed for predictive versus random sequences. In addition, the early positivity following the delay was larger for predictive compared with random sequences. These results suggest that expectation-sensitive ERP modulations can be elicited in anticipation of stimuli that are not explicit targets, rewards, feedback or instructions, and that a delay can strengthen the prediction for a particular stimulus. Applications to language processing will be discussed.

Processing gapped verbs.

The time course was investigated of the processing of "missing" verbs in gapping constructions, such as John ate the hamburger, and Bill __ the hotdog. Native speakers of Dutch silently read Dutch sentences with and without gapping while their EEG was recorded. A left anterior negativity (LAN) was found at the first possible position at which the gapped verb could be detected, at least, for in participants who performed poorly in an end-of-sentence acceptability judgment task. This suggests that some readers do not anticipate the gapped verb, but infer the gapped verb in a bottom-up fashion, resulting in a LAN. Second, a P600 effect was observed for gapping versus no-gapping conditions, the early part of which was unaffected by plausibility. This suggests that the semantic and syntactic integration of a gapped verb is a relatively late process, and involves mechanisms similar to integrating a wh-phrase object with its verb.

Changes in oscillatory brain networks after lexical tone training.

Learning foreign speech contrasts involves creating new representations of sound categories in memory. This formation of new memory representations is likely to involve changes in neural networks as reflected by oscillatory brain activity. To explore this, we conducted time-frequency analyses of electro-encephalography (EEG) data recorded in a passive auditory oddball paradigm using Thai language tones. We compared native speakers of English (a non-tone language) and native speakers of Mandarin Chinese (a tone language), before and after a two-day laboratory training. Native English speakers showed a larger gamma-band power and stronger alpha-band synchrony across EEG channels than the native Chinese speakers, especially after training. This is compatible with the view that forming new speech categories on the basis of unfamiliar perceptual dimensions involves stronger gamma activity and more coherent activity in alpha-band networks than forming new categories on the basis of familiar dimensions.

Thai lexical tone perception in native speakers of Thai, English and Mandarin Chinese: an event-related potentials training study.

BACKGROUND: Tone languages such as Thai and Mandarin Chinese use differences in fundamental frequency (F0, pitch) to distinguish lexical meaning. Previous behavioral studies have shown that native speakers of a non-tone language have difficulty discriminating among tone contrasts and are sensitive to different F0 dimensions than speakers of a tone language. The aim of the present ERP study was to investigate the effect of language background and training on the non-attentive processing of lexical tones. EEG was recorded from 12 adult native speakers of Mandarin Chinese, 12 native speakers of American English, and 11 Thai speakers while they were watching a movie and were presented with multiple tokens of low-falling, mid-level and high-rising Thai lexical tones. High-rising or low-falling tokens were presented as deviants among mid-level standard tokens, and vice versa. EEG data and data from a behavioral discrimination task were collected before and after a two-day perceptual categorization training task. RESULTS: Behavioral discrimination improved after training in both the Chinese and the English groups. Low-falling tone deviants versus standards elicited a mismatch negativity (MMN) in all language groups. Before, but not after training, the English speakers showed a larger MMN compared to the Chinese, even though English speakers performed worst in the behavioral tasks. The MMN was followed by a late negativity, which became smaller with improved discrimination. The High-rising deviants versus standards elicited a late negativity, which was left-lateralized only in the English and Chinese groups. CONCLUSION: Results showed that native speakers of English, Chinese and Thai recruited largely similar mechanisms when non-attentively processing Thai lexical tones. However, native Thai speakers differed from the Chinese and English speakers with respect to the processing of late F0 contour differences (high-rising versus mid-level tones). In addition, native speakers of a non-tone language (English) were initially more sensitive to F0 onset differences (low-falling versus mid-level contrast), which was suppressed as a result of training. This result converges with results from previous behavioral studies and supports the view that attentive as well as non-attentive processing of F0 contrasts is affected by language background, but is malleable even in adult learners.

Effects of native language and training on lexical tone perception: an event-related potential study.

Tone languages such as Thai use pitch differences to distinguish lexical meaning. Previous behavioral studies have reported that naïve listeners can discriminate among lexical tones, but that native language background affects performance. The present study uses ERPs to determine whether native speakers of a tone language (Mandarin Chinese) and of a non-tone language (English) differ in their pre-attentive discrimination among Thai lexical tones, and whether training has a different effect in these two language groups. EEGs were obtained from 10 native Mandarin Chinese speakers, 10 English and 10 Thai speakers in an oddball paradigm: The Thai syllable [k(h)a:] pronounced with a high rising or low falling tone, was presented as an infrequent deviant amidst a standard mid level tone [k(h)a:] syllable, while participants watched a silent movie. Next, the Chinese and English participants completed a 2-day perceptual identification training on the mid level and low falling tones, and returned for a post training EEG. The low falling tone deviant elicited a Mismatch Negativity (MMN) in all participant groups before and after training; the high rising deviant elicited no, or a smaller, MMN, which became larger after training only in the English group. The high rising deviant also elicited a later negativity (350-650 ms) versus the mid level standard, which decreased after training in the Chinese group. These results suggest that non-Thai speakers can pre-attentively discriminate among Thai tones, but are sensitive to different physical properties of the tones, depending on their native language. English speakers are more sensitive to early pitch differences, whereas native speakers of Mandarin Chinese are more sensitive to the (later) pitch contour.

Processing bare quantifiers in discourse.

During reading or listening, language comprehenders construct a mental representation of the objects and events mentioned. This model is augmented and modified incrementally as the discourse unfolds. In this paper we focus on the interpretation of bare quantifiers, that is, expressions such as 'two', to investigate the processes underlying the construction and modification of the discourse model. Bare quantifiers are temporarily ambiguous when sentences are processed incrementally. For instance, in 'Three ships were in the port. Two...', 'two' can either refer to a subset of the set just mentioned (e.g.,'two of the three ships'), a different set of the entities mentioned (e.g., 'two other ships'), or a set of different entities (e.g., 'two people'). Data from previous studies, and a current completion study, suggest that the subset interpretation is preferred over the establishment of a different set. The current study aimed to investigate ERP correlates of quantifier interpretation and their timing. Quantifiers that unambiguously signaled the establishment of a new referent elicited a late positive component (900-1500 ms), which we interpret as a Late Positive Complex, related to the difficulty involved in context updating. An additional 500-700 ms positivity was elicited only in a subset of readers, suggesting that there are individual differences in quantifier interpretation and the timing thereof.

Direction effects in number word comparison: an event-related potential study.

Event-related potentials were recorded to investigate the effects of direction on number word comparison. Participants saw a sequence of two number words, and next indicated whether the second number word denoted a quantity smaller or larger than the first number word, depending on the nature of the prompt. Faster and more accurate responses were obtained at the prompt for increasing number sequences than for decreasing number sequences. Event-related potentials to the second number word showed an enhanced positivity for increasing sequences. This confirms the view that numbers are mentally represented on a number line, with smaller numbers appearing before larger numbers. Direction of presentation should therefore be taken into consideration when designing studies on numerical processing.

Cross-serial dependencies in Dutch: testing the influence of NP type on processing load.

We tested the cross-linguistic generalizability of three models of sentence processing complexity--Lewis (1996), Gibson (1998, 2000), and Gordon (Gordon, Hendrick, & Johnson, 2001; Gordon, Hendrick, & Levine, 2002)--by investigating the on-line processing of cross-serial dependencies in Dutch. The number of subject-verb relations in a clause was manipulated, as well as type of noun phrase (indexical pronouns vs. proper names or full definite NPs). Several of our findings diverged from Gibson's model: Processing difficulty at the verbs was not affected by the use of proper names versus first- and second-person pronouns; an increase at the first verb was seen for full NPs versus pronouns in 3-verb constructions, which was predicted by the Gibson model, but is in contrast to Lewis's model. These findings are best explained within the framework of similarity-based inference models (Gordon et al., 2001; Gordon et al., 2002), according to which the number of similar NPs affects processing difficulty at the point of retrieval, and not specifically their discourse status or syntactic function.

Gapping: Electrophysiological evidence for immediate processing of "missing" verbs in sentence comprehension.

In the present study we use event related potentials (ERPs) to explore the time course of identification and resolution of verb gaps. ERPs were recorded while participants read sentences that contained a verb gap like Ron took/sanded the planks, and Bill Ø the hammer... Plausibility of the critical words (hammer) that followed the verb gap was manipulated. Relative to the plausible control (preceded by took), ERPs to the critical word in the implausible condition (preceded by sanded) showed an N400, followed by a positivity (P600). ERPs to determiners following gapped verbs showed a negativity between 100 and 300 ms, and a positivity between 300 and 500 ms compared to determiners in non-gapping constructions. These results suggest that the sentence processor recognizes a verb gap and reconstructs the verb information at the earliest possible occasion, and that this reconstruction process is different from the reconstruction of antecedents in other filler-gap constructions (e.g., WH gaps).

Electrophysiological evidence for serial sentence processing: a comparison between non-preferred and ungrammatical continuations.

Event-related potentials (ERPs) were used to address a much debated issue in sentence processing research, namely whether one or multiple interpretations are pursued in case of syntactic ambiguities. For example in the syntactically ambiguous fragment "The man is painting the house and the garage...", 'and' either connects 'the house' and 'the garage', or conjoins two clauses (e.g., "The man is painting the house and the garage is already finished"). According to serial models, only one syntactic interpretation (the simplest) is pursued first (the first interpretation in the example). If this interpretation is incompatible with subsequently incoming words, the syntactic analysis of the preceding sentence fragment is revised. In contrast, parallel models propose that multiple interpretations of the ambiguity are pursued simultaneously. The two models were tested by comparing ERPs to words that were either ungrammatical, or grammatical but non-preferred continuations of the preceding sentence fragment. In a serial model, these two are not distinguished until after initial revision; in a parallel model, a distinction can be made at an early stage. The results supported a serial model: both with an acceptability judgment and a passive reading task a left lateralized negativity was found for ungrammatical and non-preferred continuations relative to unambiguous grammatical continuations, which indicates that ungrammatical and non-preferred continuations were initially processed in the same way. However, in later time intervals, the ERPs to the ungrammatical continuation showed a posterior positivity (P600), whereas the ERPs to the non-preferred continuation had a more anterior focus, which indicates that they were processed differently.

Repair, revision, and complexity in syntactic analysis: an electrophysiological differentiation.

One of the core aspects of human sentence processing is the ability to detect errors and to recover from erroneous analysis through revision of ambiguous sentences and repair of ungrammatical sentences. In the present study, we used event-related potentials (ERPs) to help identify the nature of these processes by directly comparing ERPs to complex ambiguous sentence structures with and without grammatical violations, and to simpler unambiguous sentence structures with and without grammatical violations. In ambiguous sentences, preference of syntactic analysis was manipulated such that in one condition, the structures agreed with the preferred analysis, and in another condition, a nonpreferred but syntactically correct analysis (garden path) was imposed. Nonpreferred ambiguous structures require revision, whereas ungrammatical structures require repair. We found that distinct ERPs reflected different characteristics of syntactic processing. Specifically, our results are consistent with the idea that a positivity with a posterior distribution across the scalp (posterior P600) is an index of syntactic processing difficulty, including repair and revision, and that a frontally distributed positivity (frontal P600) is related to ambiguity resolution and/or to an increase in discourse level complexity.