Event-related brain potential correlates of the other-race effect: A review

People are better at remembering own-race relative to other-race faces. Here, we review event-related brain potential (ERP) correlates of this so-called other-‘race’ effect (ORE) by discussing three critical aspects that characterize the neural signature of this phenomenon. First, difficulties with other-race faces initially emerge during perceptual processing, which is indexed by an increased N170. Second, as evidenced by ‘difference due to subsequent memory’ effects, more effortful processing of other-race faces is needed for successful encoding into long-term memory. Third, ERP old/new effects reveal that a stronger engagement of processing resources is also required for successful retrieval of other-race faces from memory. The ERP evidence available to date thus suggests widespread ethnicity-related modulations during both perceptual and mnemonic processing stages. We further discuss how findings from the ORE compared with potentially related memory biases (e.g. other-gender or other-age effects) and how ERP findings inform the ongoing debate regarding the mechanisms underlying the ORE. Finally, we outline open questions and potential future directions with an emphasis on using multiple, ecologically more valid ‘ambient’ images for each face to assess the ORE in paradigms that capture identity rather than image recognition.     

不同愉悦度面孔阈下情绪启动效应:来自ERP的证据

采用事件相关电位技术,研究阈下情绪启动效应。实验中的因素是阈下呈现的情绪启动面孔的愉悦度,分为高、低两个水平。被试的任务是对中性靶刺激面孔进行情绪判断。结果发现:被试在对靶刺激进行情绪判断时出现与启动刺激愉悦度趋于一致的启动效应;低愉悦度面孔作启动刺激条件下N1和P2的波幅显著大于高愉悦度面孔作为启动刺激的条件;不同愉悦度情绪面孔的阈下启动效应是由于启动刺激影响了对靶刺激的知觉加工所致。     

Retrieval of concrete words involves more contextual information than abstract words: multiple components for the concreteness effect

The current study used the directed forgetting paradigm in implicit and explicit memory to investigate the concreteness effect. Event-related potentials (ERPs) were recorded to explore the neural basis of this phenomenon. The behavioral results showed a clear concreteness effect in both implicit and explicit memory tests; participants responded significantly faster to concrete words than to abstract words. The ERP results revealed a concreteness effect (N400) in both the encoding and retrieval phases. In addition, behavioral and ERP results showed an interaction between word concreteness and memory instruction (to-be-forgotten vs. to-be-remembered) in the late epoch of the explicit retrieval phase, revealing a significant concreteness effect only under the to-be-remembered instruction condition. This concreteness effect was realized as an increased P600-like component in response to concrete words relative to abstract words, likely reflecting retrieval of contextual details. The time course of the concreteness effect suggests advantages of concrete words over abstract words due to greater contextual information.     

On the locus of the semantic satiation effect: Evidence from event-related brain potentials

The present study sought to determine whether semantic satiation is merely a by-product of adaptation or satiation of upstream, nonsemantic perceptual processes or whether the effect can have a locus in semantic memory. This was done by measuring event-related brain potentials (ERPs) in a semantic word-detection task involving multiple presentations of primes and critical related and unrelated words in three experiments involving visual (Experiment 1) and auditory (Experiments 2A and 2B) stimuli. Primes varied in their type case (Experiment 1) or pitch (Experiment 2B) in order to discourage sensory adaptation. Prime satiation and relatedness of the primes to the critical word had interacting effects on ERP amplitude to critical words, particularly within the time-window of the N400 component. Because numerous studies have indicated a role for the N400 in semantic processing, modulation of the N400 relatedness effect by prime satiation (with little or no contribution from perceptual adaptation) suggests that semantic memory can be directly satiated, rather than the cost to semantic processing necessarily resulting from impoverishment of perceptual inputs.     

高功能孤独症者非字面语义理解缺陷：隐喻视角的ERP研究

研究采用事件相关电位技术从隐喻语义理解角度考察了高功能孤独症成人非字面语义理解中的行为特点及脑半球参与模式。行为结果显示：高功能孤独症成人对新异隐喻句的反应时最长,两类隐喻句的反应时均长于普通成人,但错误率上两组被试间无差异。脑电结果显示：高功能孤独症组对新异隐喻句的N400波幅最大,未出现半球偏侧化现象,传统隐喻句在左半球的N400波幅大于右半球,两类隐喻句的N400波幅均大于正常被试。结论：高功能孤独症成人具备隐喻理解能力,并对新异隐喻的理解做出更多努力,但右脑功能异常仍旧存在,左右半球在总体功能或神经联通性上仍旧弱于常人。     

句子语境中汉语词汇歧义消解的ERP研究

采用ERP方法,考察了汉语词汇歧义消解中句子语境作用的时间进程及大脑活动。目标词与句子语境存在一致、不一致、无关控制等3种关系。结果显示:(1)一致与不一致条件下N400的平均波幅均显著低于无关控制条件;(2)SOA为200毫秒时产生的N400平均波幅的幅度显著高于SOA为1000毫秒的条件;(3)N400的平均波幅及潜伏期均表现出左半球显著高于右半球的特点。实验结果支持词汇歧义消解的模块化观点,体现了大脑两半球语言功能的不对称性。     

Neural correlates of facial emotion processing in infancy

In the present study we examined the neural correlates of facial emotion processing in the first year of life using ERP measures and cortical source analysis. EEG data were collected cross‐sectionally from 5‐ (N = 49), 7‐ (N = 50), and 12‐month‐old (N = 51) infants while they were viewing images of angry, fearful, and happy faces. The N290 component was found to be larger in amplitude in response to fearful and happy than angry faces in all posterior clusters and showed largest response to fear than the other two emotions only over the right occipital area. The P400 and Nc components were found to be larger in amplitude in response to angry than happy and fearful faces over central and frontal scalp. Cortical source analysis of the N290 component revealed greater cortical activation in the right fusiform face area in response to fearful faces. This effect started to emerge at 5 months and became well established at 7 months, but it disappeared at 12 months. The P400 and Nc components were primarily localized to the PCC/Precuneus where heightened responses to angry faces were observed. The current results suggest the detection of a fearful face in infants’ brain can happen shortly (~200–290 ms) after the stimulus onset, and this process may rely on the face network and develop substantially between 5 to 7 months of age. The current findings also suggest the differential processing of angry faces occurred later in the P400/Nc time window, which recruits the PCC/Precuneus and is associated with the allocation of infants’ attention.     

注意促进效应的ERP研究

近期发现,采用目标探测任务作为二级任务时,目标探测条件不仅不会削弱,甚至会提高记忆成绩,产生注意促进效应（ABE）。为进一步探究目标探测的作用机制,研究采用事件相关电位（ERP）技术,对比目标与分心条件在编码和提取过程中所诱发的ERP差异。结果表明,两类条件在再认过程中所诱发的ERP差异不仅表现在早期与知觉加工相关的ERP成份上,并且一直持续到了后期与细节提取相关的ERP成分上。由此推测,ABE不仅体现在编码早期的知觉加工阶段,更会延续到后期的复述与精加工。     

Modulating younger and older adults’ performance in ignoring pictorial information during a word matching task

Using both behavioural and event-related potential (ERP) data, the current study sought to examine the neurophysiological underpinnings for the effect of distracting pictorial information on semantic word matching performance in younger and older adults. This was tested in the context of semantic relations between task-relevant word pairs, a task-irrelevant picture and the resultant N400 differences in ERP. Younger and older adults were shown a context word superimposed on a to-be-ignored picture, followed by a test word. Their task was to determine whether the prime and test words were semantically related. The to-be-ignored pictures were interfering (for ‘No’ trials), facilitating (for ‘Yes’ trials), or neutral (for both ‘Yes’ and ‘No’ trials) to the expected responses. The interfering and facilitatory effects of to-be-ignored pictures were assessed under more automatic and more controlled conditions by manipulating the context–test interstimulus-interval (ISI) as 50 ms and 1000 ms, respectively. The analysis of the N400 at centro-parietal sites during test word display revealed similar N400 amplitudes for the ‘No’ response trials at the two ISIs, suggesting that younger and older adults showed an equivalent effect from interfering pictures. In contrast, younger adults showed greater reductions in the N400, as compared to older adults, for ‘Yes’ trials indicating differential effects in facilitation from to-be-ignored pictorial information, but only in the long ISI condition. The data are discussed in terms of age differences in resource demanding strategy use during a semantic word matching task, specifically during controlled retrieval.     

Early and late mismatch negativity elicited by words and speech-like stimuli in children

In auditory perception the brain's attentional and preattentional mechanisms select certain stimuli for preferential processing and filter out irrelevant input. This study investigated nonattentive auditory processing in children. Event-related potentials (ERPs) provide a means to study neural correlates related to language and speech-sound processing. Mismatch negativity (MMN) is an ERP wave that indicates attention-independent perceptual change detection. In this study cortical ERPs were elicited by complex tones, naturally spoken words, and pseudowords, with each stimulus type containing equal acoustical elements. Tones elicited a bifurcated mismatch negativity (MMN), with early MMN (peaking at 150-200 ms) being more dominant. On the other hand, words elicited a strong late MMN, peaking at about 400-450 ms after stimulus onset. The MMN wave form was significantly weaker for pseudowords than for words. The late MMN wave, especially for word differences, was found to reflect summating MMN generators and memory trace formation on gestalt bases. Results suggest that the auditory processing, even nonattended, is highly associated with the cognitive meaning of the stimuli.     

ELECTROPHYSIOLOGICAL CORRELATES OF STIMULUS EQUIVALENCE PROCESSES

Research reported here concerns neural processes relating to stimulus equivalence class formation. In Experiment 1, two types of word pairs were presented successively to normally capable adults. In one type, the words had related usage in English (e.g., uncle, aunt). In the other, the two words were not typically related in their usage (e.g., wrist, corn). For pairs of both types, event‐related cortical potentials were recorded during and immediately after the presentation of the second word. The obtained waveforms differentiated these two types of pairs. For the unrelated pairs, the waveforms were significantly more negative about 400 ms after the second word was presented, thus replicating the “N400” phenomenon of the cognitive neuroscience literature. In addition, there was a strong positive‐tending wave form difference post‐stimulus presentation (peaked at about 500 ms) that also differentiated the unrelated from related stimulus pairs. In Experiment 2, the procedures were extended to study arbitrary stimulus—stimulus relations established via matching‐to‐sample training. Participants were experimentally näive adults. Sample stimuli (Set A) were trigrams, and comparison stimuli (Sets B, C, D, E, and F) were nonrepresentative forms. Behavioral tests evaluated potentially emergent equivalence relations (i.e., BD, DF, CE, etc.). All participants exhibited classes consistent with the arbitrary matching training. They were also exposed also to an event‐related potential procedure like that used in Experiment 1. Some received the ERP procedure before equivalence tests and some after. Only those participants who received ERP procedures after equivalence tests exhibited robust N400 differentiation initially. The positivity observed in Experiment 1 was absent for all participants. These results support speculations that equivalence tests may provide contextual support for the formation of equivalence classes including those that emerge gradually during testing.     

汉字识别中字形畸变和语境的ERP效应

以事件相关电位（ERP）技术和语义启动范式,采用同一字判断（靶字延迟反应）作业,考察字形畸变和语境对低频汉字识别的影响。结果发现,无语义启动时,畸变靶字正确率低于清晰靶字;启动效应只体现在畸变时的正确率上。150–300ms窗口,畸变字比清晰字诱发峰值更负的N170;300–500ms时间窗口,不启动条件诱发平均波幅更负的N400,畸变字诱发更大N400。结论是,畸变字诱发的N170成分,在一定程度上反映了字形加工;N400的语义启动效应和畸变效应,扩展Holcomb的研究,并支持语义提取理论。     

Interactions between sentence context and word frequencyinevent-related brainpotentials

Event-related brain potentials (ERPs) were recorded as subjects silently read a set of unrelated sentences. The ERP responses elicited by open-class words were sorted according to word frequency and the ordinal position of the eliciting word within its sentence. We observed a strong inverse correlation between sentence position and the amplitude of the N400 component of the ERP. In addition, we found that less frequent words were associated with larger N400s than were more frequent words, but only if the eliciting words occurred early in their respective sentences. We take this interaction between sentence position and word frequency as evidence that frequency does not play a mandatory role in word recognition, but can be superseded by the contextual constraint provided by a sentence.     

Relationships between event‐related potentials and behavioral and scholastic measures of reading ability: A large‐scale,cross‐sectional study

In the cognitive, computational, neuropsychological, and educational literatures, it is established that children approach text in unique ways, and that even adult readers can differ in the strategies they bring to reading. In the developmental event‐related potential (ERP) literature, however, children with differing degrees of reading ability are, the majority of the time, placed in monolithic groups such as ‘normal’ and ‘dyslexic’ (e.g. Araújo et al., 2012) and analyzed only at the group level. This is likely done due to methodological concerns – such as low sample size or a lack of statistical power – that can make it difficult to perform analysis at the individual level. Here, we collected ERPs and behavior from > 100 children in grades pre‐K–7, as they read unconnected text silently to themselves. This large sample, combined with the statistical power of the Linear Mixed Effects Regression (LMER) technique, enables us to address individual differences in ERP component effects due to reading ability at an unprecedented level of detail. Results indicate that it is possible to predict reading‐related report card scores from ERP component amplitudes – especially that of the N250, a component pertaining to sublexical processing (including phonological decoding). Results also reveal relationships between behavioral measures of reading ability and ERP component effects that have previously been elusive, such as the relationship between vocabulary and N400 mean amplitude (cf. Henderson et al., 2011). We conclude that it is possible to meaningfully examine reading‐related ERP effects at the single subject level in developing readers, and that this type of analysis can provide novel insights into both behavior and scholastic achievement.     

Stereotype activation is unintentional: Behavioural and event‐related potenials evidence

In this study, a priming Stroop paradigm was used to determine whether stereotype activation is unintentional. Priming conditions (priming/no‐priming) and the relationship between priming and target (consistent/inconsistent/no‐relation) were the independent variables; accuracy, reaction time and N400 amplitude were used as dependent variables. The reaction time revealed that stereotype activation is, to some extent, unintentional. Furthermore, the event‐related potenial (ERP) results showed that N400 amplitude was larger for inconsistent conditions than for consistent conditions. This result supported the notion that stereotype activation is an unintentional and automatic process.     

Gradients versus dichotomies: How strength of semantic context influences event-related potentials and lexical decision times

In experiments devoted to word recognition and/or language comprehension, reaction time in the lexical decision task is perhaps the most commonly used behavioral dependent measure, and the amplitude of the N400 component of the event-related potential (ERP) is the most common neural measure. Both are sensitive to multiple factors, including frequency of usage, orthographic similarity to other words, concreteness of word meaning, and preceding semantic context. All of these factors vary continuously. Published results have shown that both lexical decision times and N400 amplitudes show graded responses to graded changes of word frequency and orthographic similarity, but a puzzling discrepancy in their responsivity to the strength of a semantic context has received little attention. In three experiments, we presented pairs of words varying in the strengths of their semantic relationships, as well as unrelated pairs. In all three experiments, N400 amplitudes showed a gradient from unrelated to weakly associated to strongly associated target words, whereas lexical decision times showed a binary division rather than a gradient across strengths of relationship. This pattern of results suggests that semantic context effects in lexical decision and ERP measures arise from fundamentally different processes.     

物体分类任务中线索效应的ERP研究

本实验采用ERP技术,对图片分类任务中的线索效应进行研究。实验任务为:图形形状判断、动物/非动物判断。靶刺激图片前呈现线索。线索分为有效线索、无效线索和中性线索。结果发现:(1)有效线索条件下对靶刺激的早期知觉再认得到易化——知觉加工成分波幅下降;(2)有效线索条件下,靶刺激中与任务相关的信息得到加工——任务相关的特异性成分增强。有效线索易化对靶刺激的知觉辨认,提取与线索提供背景相关的信息,促进行为反应。     

科学语言的认知神经加工机制研究:来自ERP的证据

本研究采用尾词范式,使用ERP技术,对比分析了科学语言(隐喻和直义)与日常语言诱发的N400和LPC平均波幅和激活脑区的异同,从而探讨了科学语言认知加工机制的神经特异性。实验结果表明,与日常语言相比,在科学语言认知加工过程中,语义检索和提取难度更大,顶叶区尤其是右顶叶区的激活程度最为显著,左右脑都发挥了重要作用。此外,科学隐喻的相关研究发现支持隐喻加工的意义显性度假说,科学语言特有的复杂性和抽象性降低了语言表达的显性度,并且对后期的语义整合阶段产生影响。     

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.     

Spoken word recognition in context: evidence from Chinese ERP analyses

Two event-related potential (ERP) experiments were conducted to investigate spoken word recognition in Chinese and the effect of contextual constraints on this process. In Experiment 1, three kinds of incongruous words were formed by altering the first, second or both syllables of the congruous disyllabic terminal words in high constraint spoken sentences. Results showed an increase of N400 amplitude in all three incongruous word conditions and a delayed N400 effect in the cohort incongruous condition as compared with the rhyme incongruous and plain incongruous condition. In addition, unlike results in English, we found that the N400 effect in the rhyme incongruous condition disappeared earlier than in the plain incongruous condition. In Experiment 2, three kinds of nonwords derived from sentence congruous words were constructed by altering few or many phonetic features of the onset or the whole of the first syllable, and the resulting nonwords appeared as disyllabic terminal forms in either high or low constraint sentences. All three nonword conditions elicited the N400 component. In addition, in high constraint sentences but not in low, the amplitude and duration of the N400 varied as a function of the degree of phonetic mismatch between the terminal nonword and the expected congruous word.