N400 and P600 or the Role of the ERP Correlates in Sentence Comprehension: Some Applications to the Italian Language

In the present study, event-related brain potentials (ERPs) were applied to the study of language comprehension in the Italian language. The ERPs were recorded from 10 electrodes while the participants read (Experiment 1) or listened (Experiment 2) to sentences containing semantic or syntactic anomalies. Final words that were inconsistent with the sentence context elicited a negative wave at about 400 ms poststimulus that was more concentrated in the posterior sites of the scalp, whereas final words that were incongruous with the grammatical structure (subject-verb nonagreement) elicited a positive wave at about 600 ms poststimulus that was homogeneously distributed on the scalp. The authors found no differences based on the perceptual modality of the stimulus (visual or auditory), nor did they find different ERP correlates as a function of task relevance (explicit-implicit task induction). The available evidence indicated that the ERP response to semantic anomalies was at least partially distinct from the ERP response to syntactic anomalies, and that a syntactic parser is a plausible process included in sentence comprehension. The two semantic and syntactic effects appear as automatic processes of the decoding of the anomalies and also modality-independent processes. Cross-linguistic applications are considered in the general discussion.     

N400 and P600 or the role of the ERP correlates in sentence comprehension: some applications to the Italian language

In the present study, event-related brain potentials (ERPs) were applied to the study of language comprehension in the Italian language. The ERPs were recorded from 10 electrodes while the participants read (Experiment 1) or listened (Experiment 2) to sentences containing semantic or syntactic anomalies. Final words that were inconsistent with the sentence context elicited a negative wave at about 400 ms poststimulus that was more concentrated in the posterior sites of the scalp, whereas final words that were incongruous with the grammatical structure (subject-verb nonagreement) elicited a positive wave at about 600 ms poststimulus that was homogeneously distributed on the scalp. The authors found no differences based on the perceptual modality of the stimulus (visual or auditory), nor did they find different ERP correlates as a function of task relevance (explicit-implicit task induction). The available evidence indicated that the ERP response to semantic anomalies was at least partially distinct from the ERP response to syntactic anomalies, and that a syntactic parser is a plausible process included in sentence comprehension. The two semantic and syntactic effects appear as automatic processes of the decoding of the anomalies and also modality-independent processes. Cross-linguistic applications are considered in the general discussion.     

Brain potentials elicited by prose-embedded linguistic anomalies

Linguistic theories distinguish between syntax (sentence form) and semantics (sentence meaning). Correspondingly, recent studies have shown that syntactic and semantic anomalies elicit distinct changes in the event-related brain potential (ERP). However, these results have been obtained with highly artificial methodologies and have not yet been generalized to more natural reading conditions. Here, we recorded ERPs while subjects read a naturalistic prose passage. The subjects either read for comprehension with no other task being assigned or read for comprehension and made acceptability judgments after each sentence. Consistent with prior work and regardless of the subjects' assigned task, syntactic anomalies elicited a large positive wave (P600), whereas semantic anomalies elicited a large increase in N400 amplitude. These results demonstrate that the qualitatively distinct ERP responses elicited by syntactic and semantic anomalies are not artifacts of unnatural aspects of previously used stimuli, thereby providing additional evidence that separable syntactic and semantic processes exist.     

汉、英句法结构相似性与第二语言的熟练度对第二语言句法加工的影响

采用事件相关电位（ERP）技术,考察了汉、英句法结构相似性与第二语言（英语）熟练度对第二语言句法加工的影响。实验材料包含与汉语句法结构相似和不同的两种英语句法结构违反的句子。结果发现：与正确句子相比,相似句法违反句在高熟练组被试中,引发正向的ERP波形偏转（150-800ms）,而在低熟练组被试中,只引发了降低的N400（300-550ms）效应;对于不同句法违反句,无论高低熟悉程度的被试,均未出现显著的ERP效应。研究结果表明,第二语言句法与母语的相似性越高,加工起来更容易;第二语言熟练度水平对第二语言句法加工具有一定的促进作用,但受到两种语言句法结构相似性的影响,相似性越高,熟练度的促进作用越大。     

Comprehending Semantic and Grammatical Violations in Italian. N400 and P600 Comparison with Visual and Auditory Stimuli

Arguments about the existence of language-specific neural systems and specifically about the independence of syntactic and semantic processing have focused on the event-related brain measures (ERPs) as tool to monitoring moment-by-moment the cognitive processes underlaid. In the present experiments, the available evidence indicates that the ERP response to semantic anomalies is at least partially distinct from the ERP response to syntactic anomalies and that two distinct processes are activated in sentences comprehension. ERPs were recorded from 10 electrodes while subjects read (Experiment 1) or listened (Experiment 2) to sentences containing semantic or syntactic violations. Final-words that were inconsistent with the sentence context elicited a negative-going wave at about 400 ms poststimulus, whereas penultimate-word incongruous with the grammatical structure (subject–verb non-agreement) elicited a positive-going wave about 600 ms poststimulus. No differences based on the perceptual modality of the stimulus (visual or auditory) nor different ERP correlates as a function of task-relevance (explicit/implicit task induction) were found. The implications of our results for Italian language are explained.     

汉语句子加工中句法信息与语义信息的交互作用：来自ERP的证据

采用ERP技术考察句子加工过程中句法信息和语义信息交互作用的时间进程。以汉语“把字句”为实验材料,分别比较句法违例句与双重违例句的LAN和P600效应、语义违例句与双重违例句的N400效应。与句法违例句相比,双重违例句的LAN效应的波幅更负,潜伏期更长,皮层分布更广泛;双重违例句的P600效应出现减弱趋势;双重违例句的N400效应的潜伏期显著长于语义违例句。结果表明,在句子加工的各个阶段,句法信息和语义信息呈持续交互作用,支持句子的平行加工模型。     

Lexical integration: Sequential effects of syntactic and semantic information

Both semantic and syntactic context constraints can influence word processing at the level of lexical integration. In event-related brain potentials (ERPs), semantic integration is reflected by a negativity around 400 msec (N400), whereas phrase structure assignment and syntactic integration are assumed to be reflected by an early left anterior negativity and a late positivity (P600), respectively. An ERP study is presented in which participants read different types of sentences whose terminal verb was either congruent with the preceding context or incongruent due to a phrase structure violation, a semantic violation, or both. The main finding was that only the pure semantic violation condition, but not the combined semantic and syntactic violation condition, elicited a large N400. The two conditions containing phrase structure violations were predominantly characterized by a P600. Both semantic violation conditions, moreover, displayed a late negativity around 700 msec that overlapped with the P600 in the double violation condition. The absence of an N400 effect for elements that are syntactically as well as semantically incongruent with prior context suggests an early influence of phrase structure information on processes of lexical-semantic integration. The present data are discussed in comparison to previous ERP findings, and a new view of lexical integration processes is proposed.     

Structure and limited capacity in verbal working memory: a study with event-related potentials

In order to test recent claims about the structure of verbal working memory, two ERP experiments with Dutch speaking participants were carried out. We compared the ERP effects of syntactic and semantic mid-sentence anomalies in subject and object relative sentences. In Experiment 1, the participants made acceptability judgments, while in Experiment 2 they read for comprehension. Syntactic anomalies concerned subject-verb disagreement, while semantic anomalies were related to implausible events (e.g., *The cat that fled from the mice ran through the room). Semantic anomalies did not elicit an N400 effect. The semantic as well as syntactic anomalies elicited P600 effects, with similar centro-parietal scalp distributions. For both kinds of anomaly, the P600 effects were modulated by syntactic complexity: they were either relatively small (Experiment 1) or absent (Experiment 2) in object relative sentences. Taken together, our results suggest that: (a) verbal working memory is a limited capacity system; (b) it is not subdivided into an interpretative and a post-interpretative component (); (c) the P600 can reflect the presence of a semantic bias in syntactically unambiguous sentences; (d) the P600 is related to language monitoring: its function is to check upon the veridicality of an unexpected (linguistic) event; (e) if such a check is made, there is no integration of the event and hence no N400 effect.     

The role of structural prediction in rapid syntactic analysis

A number of recent electrophysiological studies of sentence processing have shown that a subclass of syntactic violations elicits very rapid ERP responses, occurring within around 200 ms of the onset of the violation. Such findings raise the question of how it is possible to diagnose violations so quickly. This paper suggests that very rapid diagnosis of errors is possible specifically in situations where the diagnosis problem is tightly constrained by specific expectations generated before the critical word is presented. In an event-related potentials (ERP) study of visual sentence reading participants encountered violations of a word order constraint (...Max's of...) that has elicited early ERP responses in previous studies. Across conditions the illicit sequence was held constant, while sentence context was used to manipulate the expectation for a noun following the possessor Max's, by manipulating the possibility of ellipsis of the head noun. Results showed that the anterior negativity elicited by the word category violation was attenuated when the availability of ellipsis reduced the expectation for a noun in the position of the offending preposition of, with divergence between conditions starting around 200 ms after the onset of the violation. This suggests a role for structural expectations in accounting for very fast syntactic diagnosis processes.     

Influences of semantic and syntactic context on open- and closed-class words

Event-related potentials (ERPs) were recorded as subjects read semantically meaningful, syntactically legal but nonsensical and random word strings. The constraints imposed by formal sentence structure alone did not reduce the amplitude of the N400 component elicited by open-class words, whereas semantic constraints did. Semantic constraints also eliminated the word-frequency effect of a larger N400 for low-frequency words. Responses to closed-class words exhibited reduced N400 amplitudes in syntactic and congruent sentences, indicating that formal sentence structure placed greater restrictions on closed-class words than it did on open-class words. However, unlike the open-class results, the impact of sentence context on closed-class words was stable across word positions, suggesting that these syntactic constraints were applied only locally. A second ERP component, distinct from the N400, was elicited primarily by congruent closed-class words.     

Gender Electrified: ERP Evidence on the Syntactic Nature of Gender Processing

The central issue of this study concerns the claim that the processing of gender agreement in online sentence comprehension is a syntactic rather than a conceptual/semantic process. This claim was tested for the grammatical gender agreement in Dutch between the definite article and the noun. Subjects read sentences in which the definite article and the noun had the same gender and sentences in which the gender agreement was violated. While subjects read these sentences, their electrophysiological activity was recorded via electrodes placed on the scalp. Earlier research has shown that semantic and syntactic processing events manifest themselves in different event-related brain potential (ERP) effects. Semantic integration modulates the amplitude of the so-called N400. The P600/SPS is an ERP effect that is more sensitive to syntactic processes. The violation of grammatical gender agreement was found to result in a P600/SPS. For violations in sentence-final position, an additional increase of the N400 amplitude was observed. This N400 effect is interpreted as resulting from the consequence of a syntactic violation for the sentence-final wrap-up. The overall pattern of results supports the claim that the on-line processing of gender agreement information is not a content driven but a syntactic-form driven process.     

世界知识在句子理解中的整合时程

Hagoort等(2004)应用背离范式发现世界知识和单词意义在句末的整合是同时进行的。本研究将背离信息提前到句首短语中,旨在探讨世界知识在句子阅读过程中被整合的时程特征。实验采用四词句子为材料,其中第二个词（目标词）含有单词意义或世界知识背离信息,记录并比较被试在阅读后三个词时诱发的脑电变化。结果发现：与正确句子比较,无论是单词意义背离还是世界知识背离,背离目标词均引发出经典的N400,二者在峰值时间和始潜时上无显著差异,但世界知识背离信息诱发的N400波幅值相对较小。句中的后继单词不再诱发类似的N400;但到句子结尾,两类含有背离信息句子的句末正常单词又诱发出类似N400的一个负波。结果提示,在句子理解过程中,世界知识的整合与单词意义的整合相似,可能是随着句子理解过程即时进行的,整合的结果不影响后继信息的加工;但到了句末,读者在对整个句子内容作真实性判断时会对先前进行过的整合再进行考察。     

The time course of semantic and syntactic processing in Chinese sentence comprehension: Evidence from eye movements

In the present study, we examined the time course of semantic and syntactic processing when Chinese is read. Readers’ eye movements were monitored, and the relation between a single-character critical word and the sentence context was manipulated such that three kinds of sentences were developed: (1) congruent, (2) those with a semantic violation, and (3) those with both a semantic and a syntactic violation. The eye movement data showed that the first-pass reading times were significantly longer for the target region in the two violation conditions than in the congruent condition. Moreover, the semantic + syntactic violation caused more severe disruption than did the pure semantic violation, as reflected by longer first-pass reading times for the target region and by longer go-past times for the target region and posttarget region in the former than in the latter condition. These results suggest that the effects of, at least, a semantic violation can be detected immediately by Chinese readers and that the processing of syntactic and semantic information is distinct in both first-pass and second-pass reading.     

Conflict and surrender during sentence processing: an ERP study of syntax-semantics interaction

Recent ERP studies report that implausible verb-argument combinations can elicit a centro-parietal P600 effect (e.g., "The hearty meal was devouring …"; Kim & Osterhout, 2005). Such eliciting conditions do not involve outright syntactic anomaly, deviating from previous reports of P600. Kim and Osterhout (2005) attributed such P600 effects to structural reprocessing that occurs when syntactic cues fail to support a semantically attractive interpretation ('meal' as the Agent of 'devouring') and the syntactic cues are overwhelmed; the sentence is therefore perceived as syntactically ill-formed. The current study replicated such findings and also found that altering the syntactic cues in such situations of syntax-semantics conflict (e.g., "The hearty meal would devour …") affects the conflict's outcome. P600s were eliminated when sentences contained syntactic cues that required multiple morphosyntactic steps to "repair". These sentences elicited a broad, left-anterior negativity at 300-600ms (LAN). We interpret the reduction in P600 amplitude in terms of "resistance" of syntactic cues to reprocessing. We speculate that the LAN may be generated by difficulty retrieving an analysis that satisfies both syntactic and semantic cues, which results when syntactic cues are strong enough to resist opposing semantic cues. This pattern of effects is consistent with partially independent but highly interactive syntactic and semantic processing streams, which often operate collaboratively but can compete for influence over interpretation.     

A comparison of semantic and syntactic event related potentials generated by children and adults

The present study employs event related potentials (ERPs) to verify the utility of using electrophysiological measures to study developmental questions within the field of language comprehension. Established ERP components (N400 and P600) that reflect semantic and syntactic processing were examined. Fifteen adults and 14 children (ages 8-13) processed spoken stimuli containing either semantic or syntactic anomalies. Adult participants showed a significant N400 in response to semantic anomalies and P600 components in response to syntactic anomalies. Children also show evidence of both ERP components. The children's N400 component differed from the adults' in scalp location, latency, and component amplitude. The children's P600 was remarkably similar to the P600 shown by adults in scalp location, component amplitude, and component latency. Theoretical implication for theories of language comprehension in adults and children will be discussed.     

EEG theta and gamma responses to semantic violations in online sentence processing

We explore the nature of the oscillatory dynamics in the EEG of subjects reading sentences that contain a semantic violation. More specifically, we examine whether increases in theta ( approximately 3-7 Hz) and gamma (around 40 Hz) band power occur in response to sentences that were either semantically correct or contained a semantically incongruent word (semantic violation). ERP results indicated a classical N400 effect. A wavelet-based time-frequency analysis revealed a theta band power increase during an interval of 300-800 ms after critical word onset, at temporal electrodes bilaterally for both sentence conditions, and over midfrontal areas for the semantic violations only. In the gamma frequency band, a predominantly frontal power increase was observed during the processing of correct sentences. This effect was absent following semantic violations. These results provide a characterization of the oscillatory brain dynamics, and notably of both theta and gamma oscillations, that occur during language comprehension.     

Brain potentials for derivational morphology: an ERP study of deadjectival nominalizations in Spanish

This study investigates brain potentials to derived word forms in Spanish. Two experiments were performed on derived nominals that differ in terms of their productivity and semantic properties but are otherwise similar, an acceptability judgment task and a reading experiment using event-related brain potentials (ERPs) in which correctly and incorrectly formed derived words were presented in sentence contexts. The first experiment indicated productivity differences between the different nominalization processes in Spanish. The second experiment yielded a pattern of ERP responses that differed from both the familiar lexical-semantic and grammatical ERP effects. Violations of derivational morphology elicited an increased N400 component plus a late positivity (P600), unlike gender-agreement violations, which produced the biphasic LAN/P600 ERP pattern known from previous studies of morpho-syntactic violations. We conclude that the recognition of derived word forms engages both word-level (lexical-semantic) and decompositional (morpheme-based) processes.     

主题与类属关系的距离对分类和属性推理过程的影响：来自ERP的证据

不同关系类型对归纳推理具有重要的影响,然而主题关系（如,熊猫vs.竹子）与类属关系（如,熊猫vs.羚羊）在归纳推理中的神经机制仍然不清楚。本研究采用事件相关电位（ERP）技术,通过分开呈现属性归纳推理任务中的结论类别和结论属性,探讨两种关系类型及其距离在分类过程和属性推理过程中的ERP特征。结果发现：（1）结论类别呈现阶段,N400（370～500 ms）与LNC（the late negative component）（570～700 ms）时间窗口上,无论是主题关系还是类属关系,远距离比近距离均诱发了更大的负波;前者表明N400与语义整合密切相关,后者说明LNC与语义类别信息违背和假设形成有关。（2）结论属性呈现阶段,主题关系比类属关系诱发了更大的N1;同时,近距离比远距离诱发了更大的N1,反映了类别属性特征的知觉和自动化加工。结果表明：语义类别属性归纳存在距离效应,并且语义关系在属性推理过程中具有不同的加工方式。     

Examining the evidence for an independent semantic analyzer: an ERP study in Spanish

Recent ERP findings challenge the widespread assumption that syntactic and semantic processes are tightly coupled. Syntactically well-formed sentences that are semantically anomalous due to thematic mismatches elicit a P600, the component standardly associated with syntactic anomaly. This ‘thematic P600’ effect has been attributed to detection of semantically plausible thematic relations that conflict with the surface syntactic structure of the sentence, implying a processing architecture with an independent semantic analyzer. A key finding is that the P600 is selectively sensitive to the presence of plausible verb-argument relations, and that otherwise an N400 is elicited (The hearty meal was devouring … vs. The dusty tabletop was devouring …: Kim & Osterhout, 2005). The current study investigates in Spanish whether the evidence for an independent semantic analyzer is better explained by a standard architecture that rapidly integrates multiple sources of lexical, syntactic, and semantic information. The study manipulated the presence of plausible thematic relations, and varied the choice of auxiliary between passive-biased fue and active-progressive biased estaba. Results show a late positivity that appeared as soon as comprehenders detected an improbable combination of subject animacy, auxiliary bias, or verb voice morphology. This effect appeared at the lexical verb in the fue conditions and at the auxiliary in the estaba conditions. The late positivity elicited by surface thematic anomalies was the same, regardless of the presence of a plausible non-surface interpretation, and no N400 effects were elicited. These findings do not implicate an independent semantic analyzer, and are compatible with standard language processing architectures.     

语义整合的早期加工:来自ERPs的证据

本研究借助ERPs技术,通过操纵关键词与当前语境的语义合理性关系,考察在严格限定关键词词频变异性的情况下,语义整合过程能否反映在P2效应上。ERPs结果发现关键词呈现后,语义合理相比违背条件在右侧脑区诱发了更大的P2成分。该结果支持如果关键词低水平的变量信息(词频等)得到适当控制,ERPs技术可以检测到发生在250ms以前的语义整合过程。