Event-related Brain Potential Study Research Articles

Neural evidence for the subliminal processing of facial trustworthiness in infancy

Face evaluation is thought to play a vital role in human social interactions. One prominent aspect is the evaluation of facial signs of trustworthiness, which has been shown to occur reliably, rapidly, and without conscious awareness in adults. Recent developmental work indicates that the sensitivity to facial trustworthiness has early ontogenetic origins as it can already be observed in infancy. However, it is unclear whether infants’ sensitivity to facial signs of trustworthiness relies upon conscious processing of a face or, similar to adults, occurs also in response to subliminal faces. To investigate this question, we conducted an event-related brain potential (ERP) study, in which we presented 7-month-old infants with faces varying in trustworthiness. Facial stimuli were presented subliminally (below infants’ face visibility threshold) for only 50ms and then masked by presenting a scrambled face image. Our data revealed that infants’ ERP responses to subliminally presented faces differed as a function of trustworthiness. Specifically, untrustworthy faces elicited an enhanced negative slow wave (800–1000ms) at frontal and central electrodes. The current findings critically extend prior work by showing that, similar to adults, infants’ neural detection of facial signs of trustworthiness occurs also in response to subliminal face. This supports the view that detecting facial trustworthiness is an early developing and automatic process in humans.

The cognitive and neural basis of developmental prosopagnosia.

Developmental prosopagnosia (DP) is a severe impairment of visual face recognition in the absence of any apparent brain damage. The factors responsible for DP have not yet been fully identified. This article provides a selective review of recent studies investigating cognitive and neural processes that may contribute to the face recognition deficits in DP, focusing primarily on event-related brain potential (ERP) measures of face perception and recognition. Studies that measured the face-sensitive N170 component as a marker of perceptual face processing have shown that the perceptual discrimination between faces and non-face objects is intact in DP. Other N170 studies suggest that faces are not represented in the typical fashion in DP. Individuals with DP appear to have specific difficulties in processing spatial and contrast deviations from canonical upright visual-perceptual face templates. The rapid detection of emotional facial expressions appears to be unaffected in DP. ERP studies of the activation of visual memory for individual faces and of the explicit identification of particular individuals have revealed differences between DPs and controls in the timing of these processes and in the links between visual face memory and explicit face recognition. These observations suggest that the speed and efficiency of information propagation through the cortical face network is altered in DP. The nature of the perceptual impairments in DP suggests that atypical visual experience with the eye region of faces over development may be an important contributing factor to DP.

An ERP study on hostile attribution bias in aggressive and nonaggressive individuals

Hostile attribution bias (e.g., tendency to interpret the intention of others as hostile in ambiguous social contexts) has been associated with impulsive aggression in adults, but the results are mixed and the complete sequence of hostile inferential processes leading to aggression has not been investigated yet. The goal of this event-related brain potentials (ERPs) study was to track the neural activity associated with the violation of expectations about hostile versus nonhostile intentions in aggressive and nonaggressive individuals and examine how this neural activity relates to self-reported hostile attributional bias and impulsive aggression in real life. To this end, scenarios with a hostile versus nonhostile social context followed by a character's ambiguous aversive behavior were presented to readers, and ERPs to critical words that specified the hostile versus nonhostile intent behind the behavior were analysed. Thirty-seven aggressive and fifty nonaggressive individuals participated in the study. The presentation of a critical word that violated hostile expectation caused an N400 response that was significantly larger in aggressive than nonaggressive individuals. Results also showed an enhanced late positive potential-like component in aggressive individuals when hostile intention scenarios took place in a nonhostile context, which is associated with impulsive aggression in real life even after having controlled for the effect of self-reported hostile attributional bias. The Hostile Expectancy Violation paradigm evaluated in this study represents a promising tool to investigate the relationship between the online processing of hostile intent in others and impulsive aggression. Aggr. Behav. 43:217-229, 2017. © 2016 Wiley Periodicals, Inc.

Psychometric considerations in the measurement of event-related brain potentials: Guidelines for measurement and reporting

Failing to consider psychometric issues related to reliability and validity, differential deficits, and statistical power potentially undermines the conclusions of a study. In research using event-related brain potentials (ERPs), numerous contextual factors (population sampled, task, data recording, analysis pipeline, etc.) can impact the reliability of ERP scores. The present review considers the contextual factors that influence ERP score reliability and the downstream effects that reliability has on statistical analyses. Given the context-dependent nature of ERPs, it is recommended that ERP score reliability be formally assessed on a study-by-study basis. Recommended guidelines for ERP studies include 1) reporting the threshold of acceptable reliability and reliability estimates for observed scores, 2) specifying the approach used to estimate reliability, and 3) justifying how trial-count minima were chosen. A reliability threshold for internal consistency of at least 0.70 is recommended, and a threshold of 0.80 is preferred. The review also advocates the use of generalizability theory for estimating score dependability (the generalizability theory analog to reliability) as an improvement on classical test theory reliability estimates, suggesting that the latter is less well suited to ERP research. To facilitate the calculation and reporting of dependability estimates, an open-source Matlab program, the ERP Reliability Analysis Toolbox, is presented.

Neural mechanisms underlying attribution of hostile intention in nonaggressive individuals: An ERP study

Although the perception of hostile intentions in other people can have a clear adaptive function, researchers have paid little attention to the capacity of nonaggressive individuals to infer hostile intentions in others. The goal of the present study was to study brain mechanisms associated with expectations of hostile/non-hostile intent and their on-line evaluation. Scenarios with a hostile versus non-hostile social context followed by a character's ambiguous aversive behavior were presented to readers, and we recorded and analyzed event-related brain potentials (ERPs) to critical words that disambiguated the hostile versus non-hostile intent behind the behavior. Fifty nonaggressive individuals participated in the study. Non-hostile critical words that violated hostile intention expectations elicited a larger negative-going ERP deflection with central and posterior maximums between 400 and 600ms after word onset compatible with an N400 effect. Finally, there were marginally significant correlations between N400 effect sizes and hostile as well as neutral attribution bias measured by a self-report questionnaire. The results suggest that nonaggressive individuals evaluate rapidly, on-line, their attributions of the hostile intent of others. The methodology we developed provides the field with a new paradigm with which to study social attributions of hostile intent likely to contribute to hostile or aggressive reactions.

A sheet of coffee: an event-related brain potential study of the processing of classifier-noun sequences in English and Mandarin

ABSTRACTComprehension of classifier-noun sequences was examined in separate studies in English and Mandarin by comparing event-related brain potential (ERP) responses to classifier-noun matches (a sheet of paper) and mismatches (a sheet of coffee) embedded in sentences. One goal was to determine which ERP components are sensitive to such mismatches, as a clue about the nature of the underlying combinatorial processes. Another goal was to examine effects of classifier constraint strength (a piece of … vs. a sheet of … ) on anticipation of a subsequent noun. Results were similar in the two languages, which is remarkable given substantial differences between them in classifier usage. In both languages, nouns evoked larger N400s in mismatching classifier-noun sequences, suggesting that combinatorial processing was primarily semantic, and general classifiers evoked a larger sustained frontal negativity than specific classifiers starting 200 milliseconds after classifier onset, reflecting effects of constraint strength on anticipation of the upcoming noun.

Impaired context processing during irony comprehension in schizotypy: An ERPs study

Mentalizing deficits are a core manifestation of schizophrenia spectrum disorders. They contribute to the social handicap associated with the pathology, leading to disruption in autonomy, professional achievement, and interpersonal relationships. However, the underlying mechanisms of these deficits remain poorly understood. The aim of the present study was to test the hypothesis that context processing deficits would be responsible for mentalizing difficulties in schizotypy (personality traits considered as attenuated manifestations of schizophrenic symptoms) by using an irony comprehension task. Irony processing is a mentalizing exercise that requires the ability to take into account the semantic context to understand the literal meaning of the utterance, and to integrate the pragmatic context to infer the speaker's intention. These two steps of processing can be indexed by the N400 and P600 components, respectively, of event-related brain potentials (ERPs). Forty participants were assigned to high or low schizotypy groups according to their Schizotypal Personality Questionnaire (SPQ) score, and ERPs were recorded while they read short stories ending with a literal, ironic, or incompatible statement. In the low-SPQ group, there was a significant N400 semantic context effect (literal targets elicited less negative N400 amplitudes compared to incompatible targets) followed by a P600 pragmatic context effect (ironic targets evoked greater positive P600 amplitudes than literal targets). In contrast, there was neither a N400 nor P600 effect in the high-SPQ group. These abnormalities were associated with high interpersonal SPQ factor scores. These results show a strong association between context processing, mentalizing abilities, and interpersonal functioning in schizophrenia spectrum.

Hemispheric asymmetry in event knowledge activation during incremental language comprehension: A visual half-field ERP study

During incremental language comprehension, the brain activates knowledge of described events, including knowledge elements that constitute semantic anomalies in their linguistic context. The present study investigates hemispheric asymmetries in this process, with the aim of advancing our understanding of the neural basis and functional properties of event knowledge activation during incremental comprehension. In a visual half-field event-related brain potential (ERP) experiment, participants read brief discourses in which the third sentence contained a word that was either highly expected, semantically anomalous but related to the described event (Event-Related), or semantically anomalous but unrelated to the described event (Event-Unrelated). For both visual fields of target word presentation, semantically anomalous words elicited N400 ERP components of greater amplitude than did expected words. Crucially, Event-Related anomalous words elicited a reduced N400 relative to Event-Unrelated anomalous words only with left visual field/right hemisphere presentation. This result suggests that right hemisphere processes are critical to the activation of event knowledge elements that violate the linguistic context, and in doing so informs existing theories of hemispheric asymmetries in semantic processing during language comprehension. Additionally, this finding coincides with past research suggesting a crucial role for the right hemisphere in elaborative inference generation, raises interesting questions regarding hemispheric coordination in generating event-specific linguistic expectancies, and more generally highlights the possibility of functional dissociation of event knowledge activation for the generation of elaborative inferences and for linguistic expectancies.

Students’ Mindsets for Learning and Their Neural Underpinnings

It has been shown that individuals with a growth mindset for learning see mistakes as opportunities to learn and improve, whereas for fixed-minded individuals mistakes indicate lack of ability. Earlier empirical research on mindsets includes both quantitative surveys and qualitative approaches with observations and stimulated recall method. During performance monitoring it is possible to probe event-related brain potentials (ERPs), enabling the investigation of the neural basis of students’ different reactions to mistakes. ERP studies have shown that growth mindset is associated with an enhancement of the error positivity (Pe), an ERP reflecting awareness of and attention allocation to mistakes. More growth-minded individuals also show superior accuracy after mistakes compared to those endorsing more of a fixed mindset. Most importantly, Pe amplitude mediates the relationship between mindset and post-error accuracy. These results suggest that neural activity indexing online awareness of and attention to mistakes is intimately involved in growth-minded individuals’ ability to rebound from mistakes. In this article we review and connect educational, psychological and neuroscientific points of view to investigate the role of mindsets related to learning.

Electrophysiology of cross-language interference and facilitation in picture naming

Disagreement exists about how bilingual speakers select words, in particular, whether words in another language compete, or competition is restricted to a target language, or no competition occurs. Evidence that competition occurs but is restricted to a target language comes from response time (RT) effects obtained when speakers name pictures in one language while trying to ignore distractor words in another language. Compared to unrelated distractor words, RT is longer when the picture name and distractor are semantically related, but RT is shorter when the distractor is the translation of the name of the picture in the other language. These effects suggest that distractor words from another language do not compete themselves but activate their counterparts in the target language, thereby yielding the semantic interference and translation facilitation effects. Here, we report an event-related brain potential (ERP) study testing the prediction that priming underlies both of these effects. The RTs showed semantic interference and translation facilitation effects. Moreover, the picture-word stimuli yielded an N400 response, whose amplitude was smaller on semantic and translation trials than on unrelated trials, providing evidence that interference and facilitation priming underlie the RT effects. We present the results of computer simulations showing the utility of a within-language competition account of our findings.

Accessing characters in spoken Chinese disyllables: An ERP study on the resolution of auditory ambiguity

Chinese differs from most Indo-European languages in its phonological, lexical, and syntactic structures. One of its unique properties is the abundance of homophones at the monosyllabic/morphemic level, with the consequence that monosyllabic homophones are all ambiguous in speech perception. Two-morpheme Chinese words can be composed of two high homophone-density morphemes (HH words), two low homophone-density morphemes (LL words), or one high and one low homophone-density morphemes (LH or HL words). The assumption of a simple inhibitory homophone effect is called into question in the case of disyllabic spoken word recognition, in which the recognition of one morpheme is affected by semantic information given by the other. Event-related brain potentials (ERPs) were used to trace on-line competitions among morphemic homophones in accessing Chinese disyllables. Results showing significant differences in ERP amplitude when comparing LL and LH words, but not when comparing LL and HL words, suggested that the first morpheme cannot be accessed without feedback from the second morpheme. Most importantly, analyses of N400 amplitude among different densities showed a converse homophone effect in which LL words, rather than LH or HL words, triggered larger N400. These findings provide strong evidence of a dynamic integration system at work during spoken Chinese disyllable recognition.

Do discourse global coherence and cumulated information impact on sentence syntactic processing? An event-related brain potentials study

The present study aimed at exploring how two main primarily semantic factors of discourse comprehension, namely global coherence and amount of information cumulated across a passage, may impact on the sentential syntactic processing. This was measured in two event-related brain potentials (ERP) to grammatical (morphosyntactic) violations: anterior negativities (LAN) and posterior positivities (P600). Global coherence did not yield any significant effects on either ERP component, although it appeared advantageous to the detection of morphosyntactic errors. Anterior negativities were also unaffected by the amount of cumulated information. Accordingly, it seems that first-pass syntactic processes are unaffected by these discourse variables. In contrast, the first portion of the P600 was significantly modulated (increased) by the latter factor. This probably reflects bigger efforts to combine sentential information during situations highly demanding for working memory. Our results would suggest that processes involved in global discourse coherence appear relatively independent of the on-line syntactic and combinatorial mechanisms reflected in the LAN and the P600 components of the ERPs.

The effect of domain-general inhibition-related training on language switching: An ERP study

Previous studies have demonstrated that inhibitory control ability could be improved by training, and the Inhibitory Control (IC) Model implies that enhanced domain-general inhibition may elicit certain changes in language switch costs. In the present study, we aimed to examine the effects of domain-general inhibition training on performance in a language switching task, including which phase of domain-general inhibitory control benefits from training during an overt picture naming task in L1 and L2, using the event-related brain potentials (ERPs). Results showed that the language switch costs of bilinguals with high inhibitory control (high-IC) were symmetrical in both pretest and posttest, and those of bilinguals with low inhibitory control (low-IC) were asymmetrical in the pretest, but symmetrical in the posttest. Moreover, the high-IC group showed a larger LPC (late positive component) for L2 switch trials than for L1 trials in both pretest and posttest. In contrast, the low-IC group only exhibited a similar pattern of LPC in the posttest, but not in the pretest. These results indicate that inhibition training could increase the efficiency of language switching, and inhibitory control may play a key role during the lexical selection response phase. Overall, the present study is the first one to provide electrophysiological evidence for individual differences in the domain-general inhibition impact on language switching performance in low-proficient bilinguals.

Can we distinguish an “I” and “ME” during listening?—an event-related EEG study on the processing of first and second person personal and possessive pronouns

Theoretically, stimuli can be related to the self as subject (“I”) or object (“ME”) of experience. This event-related brain potential (ERP) study investigated whether listening to personal and possessive pronouns elicits different modes of self-processing regarding time-course and neural sources. Going beyond previous research, first (1PP) and second person (2PP) pronouns were included to determine the specificity of self-processing. Participants listened passively to German pronouns while the electroencephalogram was recorded. Modulation of ERPs revealed a processing advantage for the 2PP personal pronoun “du” (“you”) already in early time windows. Regarding possessive pronouns, N1 amplitudes indicated increased attention orientation to the 1PP pronoun “mein” (“my”), whereas during later time windows, processing of 1PP and 2PP possessive pronouns did not differ but differed from the third person pronoun “sein” (“his”). ERP source imaging suggests that primary sensory brain regions (auditory cortex), the insula and cortical midline structures are differentially involved into these two processing modes. The results support the idea of distinct self-processing modes (“I” and “ME”) and confirm their dynamic nature. Moreover, they demonstrate that on a neural level neither “I” or “ME” are invariantly tied to the first person, in line with the hypothesis that self-processing is relational and context-dependent.

Random Number Generation and Executive Functions in Parkinson's Disease: An Event-Related Brain Potential Study.

The generation of random sequences is considered to tax executive functions and has been reported to be impaired in Parkinson's disease (PD) previously. To assess the neurophysiological markers of random number generation in PD. Event-related potentials (ERP) were recorded in 12 PD patients and 12 age-matched normal controls (NC) while either engaging in random number generation (RNG) by pressing the number keys on a computer keyboard in a random sequence or in ordered number generation (ONG) necessitating key presses in the canonical order. Key presses were paced by an external auditory stimulus at a rate of 1 tone every 1800 ms. As a secondary task subjects had to monitor the tone-sequence for a particular target tone to which the number "0" key had to be pressed. This target tone occurred randomly and infrequently, thus creating a secondary oddball task. Behaviorally, PD patients showed an increased tendency to count in steps of one as well as a tendency towards repetition avoidance. Electrophysiologically, the amplitude of the P3 component of the ERP to the target tone of the secondary task was reduced during RNG in PD but not in NC. The behavioral findings indicate less random behavior in PD while the ERP findings suggest that this impairment comes about, because attentional resources are depleted in PD.

ERP correlates of prosody and syntax interaction in case of embedded sentences

Abstract Understanding spoken language depends on processing the delicate combination of grammatical structure, meaning and prosody of utterances. Previous studies have established that prosody influences the processing of sentences when the grammatical structure is ambiguous, however it is unclear how closely prosody and syntax are related when there is no ambiguity. In an event-related brain potential (ERP) study, we investigated the processing of embedded normal and pseudosentences in which all function and content words were replaced by meaningless words. Sentences could have either natural prosodic structure or incongruent prosodic structure, where the prosody deviated from the one expected based on the syntactic structure, but otherwise the sentences were unambiguous. The resulting ERP components (CPS) showed that the construction of prosodic structure was similar in normal and pseudosentences, thus suggesting that prosody has an abstract, recursive representation, independent of other linguistic information. Moreover, we found evidence that the incongruent prosody was not only detected (shown by the RAN), but it induced neural reintegration processes (shown by the P600) in spite of the syntactic structure of sentences being intact. These results suggest that the prosodic structure is a mandatory constituent of sentence structure building whenever it is present.

Conveying the concept of movement in music: An event-related brain potential study

This study on event-related brain potential investigated whether music can convey the concept of movement. Using a semantic priming paradigm, natural musical excerpts were presented to non-musicians, followed by semantically congruent or incongruent pictures that depicted objects either in motion or at rest. The priming effects were tested in object decision and implicit recognition tasks to distinguish the effects of automatic conceptual activation from response competition. Results showed that in both tasks, pictures that were incongruent to preceding musical excerpts elicited larger N400 than congruent pictures, suggesting that music can prime the representations of movement concepts. Results of the multiple regression analysis showed that movement expression could be well predicted by specific acoustic and musical features, indicating the associations between music per se and the processing of iconic musical meaning.

An ERP study of plural attraction in attachment ambiguity resolution: Evidence for retrieval interference

Abstract The memory retrieval processes involved in subject–verb agreement processing in sentence comprehension were examined by recording event-related brain potentials (ERPs) while people read temporarily ambiguous relative clause structures such as The reporter shocked the advisor(s) of the politician(s) who was/were at the meeting . When the relative clause verb was singular, forcing attachment to whichever of the nouns was also singular, the presence of a nearby plural attractor noun created greater interference in the process of retrieving the verb's subject from the memory representation of the sentence so far, revealed by an increased frontal negativity when the attractor noun was plural compared to when it was singular. Crucially, attraction effects did not interact with attachment type. The data suggest that plural attraction effects may arise from retrieval interference in grammatical sentences. The data also suggest that interference from plural attractor nouns in agreement processing is just another instance of the retrieval interference effects that arise whenever it becomes necessary to search the memory representation of a sentence so far to form dependency relationships among the words in the sentence.

How do you know I was about to say “book”? Anticipation processes affect speech processing and lexical recognition

Most event-related brain potential (ERP) studies that showed the role of anticipation processes during sentence processing focused on reading. However, in everyday conversation speech unfolds at higher speed; the present study examines whether comprehenders anticipate words when processing auditory sentences. In high-constrained Spanish sentences, we time-locked ERPs on the article preceding the critical noun, which was muted to avoid overlapping effects. Articles that mismatched the gender of the expected nouns triggered an early (200–280 ms) and a late negativity (450–900 ms), suggesting that anticipation processes are at play also during speech processing. A subsequent lexical recognition task revealed that (muted) “expected” words were (falsely) recognised significantly more often than (muted) “unexpected” words, and as often as “old” words that were actually presented. These results suggest that anticipation processes allow creating a memory trace of a word prior to presentation. The findings support a top-down view of spoken sentence comprehension.

Neurophysiological correlates of emotional directed-forgetting in persons with Schizophrenia: An event-related brain potential study

BackgroundRecent research has shown that patients with schizophrenia (SCZ) exhibit reduced directed forgetting (DF) for negative words, suggesting impaired ability to instantiate goal-directed inhibition in order to suppress a competing, emotion-driven responses (i.e., emotional memory enhancement). However, disrupted inhibition is not the only possible mechanism by which patients could manifest reduced emotional DF. Therefore, the primary objective of the current study was to use event-related brain potential (ERP) recordings to investigate alternative hypotheses. MethodsERPs were recorded while patients and controls completed an item-method DF paradigm using negative and neutral words. The N2 indexed goal-directed inhibition of to-be-forgotten items. The late positive potential (LPP) indexed emotional memory enhancement for negative study items. The P300 indexed selective rehearsal of to-be-remembered items. ResultsThe SCZ group exhibited a reduced DF effect overall, but this was not modulated by emotion. N2 amplitude at anterior sites was larger for forget versus remember cues in the control group only, but this effect was not modulated by emotion. LPP amplitude was greater for negative versus neutral words in both groups, independent of region. P300 amplitude at posterior sites was greater for remember versus forget cues in the control group only. DiscussionThese data suggest that reduced DF in SCZ may be due, in part, to both diminished goal-directed inhibition of to-be-forgotten items and reduced selective rehearsal of to-be-remembered items. However, these data do not support the hypothesis that goal-directed, inhibitory processes are disrupted by competing, emotion-driven processes in SCZ. Patients' ERP data also suggested that they did not exhibit disproportionately heightened encoding of emotional stimuli, nor did they have deficient selective rehearsal of to-be-remembered emotional items.