Visual processing of music notation: a study of event-related potentials

In reading music, the acquisition of pitch information depends mostly on the spatial position of notes, hence more spatial processing, whereas the acquisition of temporal information depends mostly on the visual features of notes and object recognition. This study used both electrophysiological and behavioral methods to compare the processing of pitch and duration in reading single musical notes. It was observed that in the early stage of note reading, identification of pitch could elicit greater N1 and N2 amplitude than identification of duration at the parietal lobe electrodes. In the later stages of note reading, identifying pitch elicited a greater negative slow wave at parietal electrodes than did identifying note duration. The sustained contribution of parietal processes for pitch suggests that the dorsal pathway is essential for pitch processing. However, the duration task did not elicit greater amplitude of any early ERP components than the pitch task at temporal electrodes. Accordingly, a double dissociation, suggesting involvement of the dorsal visual stream, was not observed in spatial pitch processing and ventral visual stream in processing of note durations.     

Effects of negative content on the processing of gender information: An event-related potential study

Previous research on emotion in language has mainly concerned the impact of emotional information on several aspects of lexico-semantic analyses of single words. However, affective influences on morphosyntactic processing are less understood. In the present study, we focused on the impact of negative valence in the processing of gender agreement relations. Event-related potentials (ERPs) were recorded while participants read three-word phrases and performed a syntactic judgment task. Negative and neutral adjectives could agree or disagree in gender with the preceding noun. At an electrophysiological level, the amplitude of a left anterior negativity (LAN) to gender agreement mismatches decreased in negative words, relative to neutral words. The behavioral data suggested that LAN amplitudes might be indexing the processing costs associated with the detection of gender agreement errors, since the detection of gender mismatches resulted in faster and more accurate responses than did the detection of correct gender agreement relations. According to this view, it seems that negative content facilitated the processes implicated in the early detection of gender agreement mismatches. However, gender agreement violations in negative words triggered processes involved in the reanalysis and repair of the syntactic structure, as reflected in larger P600 amplitudes to incorrect than to correct phrases, irrespective of their emotional valence.     

Semantic processing without conscious identification: evidence from event-related potentials

Three event-related potential (ERP) experiments examined whether semantic content can be accessed from visually presented words that cannot be consciously identified. Category labels were shown to participants, followed by masked, briefly exposed words that were either exemplars of the category or not exemplars. The task was to verify the category, by guessing if necessary, and to identify the word, naming it if possible. Exposure durations were selected to allow identification in approximately half the trials. For identified words, there was a marked difference in the ERP response between in-category and out-of-category words because of an N400 component. For unidentified words, there was a similar although smaller difference. Conscious identification was defined using a variety of approaches: verbal report, 6-alternative forced choice, and binary categorization (in the context of the regression method; A. G. Greenwald, M. R. Klinger, & E. S. Schuh, 1995). By any definition, ERPs for unidentified words showed evidence of semantic processing. In addition, there were differences in the neuronal populations recruited to process above-threshold versus below-threshold words, suggesting qualitative differences.     

Semantic processing of words, cognitive resources and N400: an event-related potentials study

The specificity of the right hemisphere (RH) contribution to the semantic processing of words is still debated. Indeed, the semantic impairments of right hemisphere damaged (RHD) subjects may be the expression of limited general cognitive resources rather than a specific impairment of semantic processing ([Monetta et al., 2001]; [Murray, 2000]). The purpose of this study was to evaluate the possibility that the N400 reflect the availability of cognitive resources through an analysis of its different amplitudes according to different semantic complexity level. Ten young adults without any history of neurological damage participated in a semantic categorization task with two different levels of difficulty based on prototypicality. Event related potential (ERP) signals from 64 electrodes were recorded. An N400 was observed during the processing of difficult words and distractors. The results show that the greatest N400 activation was observed during the processing of difficult words, thus reflecting a possible increase in the amount of required cognitive resources.     

Analysis of information processing stages using event-related potentials.

The event-related potential (ERP) was recorded to identify the time epochs during which different independent variables have their effects on stages in a memory search task. Stimulus intensity, memory set size and response type were varied. For the most part, the order and timing of effects (evaluated by Principal Components Analysis of within-subjects ERP differences) were consistent with the presumed underlying stages, except for early effects of response type prior to memory set effects (suggesting precategorical target recognition). The usefulness of this type of analysis for the investigation of information processing stages is discussed.     

Effects of implicit power motive on the processing of anger faces: An event-related potential study

Implicit motives are one form of motivation that regulates cognitive and emotional processing. In this study, we investigated the impact of implicit power motive (nPower) on the processing of anger faces. Event-related potentials were recorded while high- and low-nPower individuals performed a face version of an emotion Stroop task comprised of anger and neutral faces. It was found that nPower does not modify early perceptual and attentional components (P2 and N2), but a later component is affected. Indeed, power-motivated participants showed enhanced P3/LPPs (Late positive potentials) amplitude compared to low-nPower subjects, in response to anger stimuli. These findings demonstrate that anger faces have greater salience for high-nPower individuals and are subject to a more salient, conscious processing.     

Tracking the timecourse of social perception: the effects of racial cues on event-related brain potentials

Event-related potentials were used to track social perception processes associated with viewing faces of racial ingroup and outgroup members. Activity associated with three distinct processes was detected. First, peaking at approximately 170 ms, faces were distinguished from nonface stimuli. Second, peaking at approximately 250 ms, ingroup members were differentiated from outgroup members, with a larger component suggesting greater attention to ingroup members. This effect may reflect the spontaneous application of a deeper level of processing to ingroup members. Third, peaking at approximately 520 ms, evaluative differentiation of ingroup and outgroup members occurred, with greater ingroup bias displayed by those with higher levels of prejudice on an explicit measure. Together, the results demonstrate the promise of using neural processes to track the presence, timing, and degree of activation of components relevant to social perception, prejudice, and stereotyping.     

Object substitution masking interferes with semantic processing: evidence from event-related potentials

Object substitution masking (OSM) refers to impaired target identification caused by common onset, but delayed offset, of a surrounding dot mask. This effect has been hypothesized to reflect reentrant processes that result in the mask replacing the target representation. However, little is known about the depth of processing associated with masked targets in this paradigm. We investigated this issue by examining the effect of OSM on the N400 component of the event-related potential, which reflects the degree of semantic mismatch between a target and its context. Participants read a context word followed by a semantically related or unrelated target word surrounded by dots. As expected, delayed dot offset significantly reduced accuracy in identifying the target. The N400 amplitude was also diminished by OSM. These findings offer the first evidence that substitution interferes with target processing prior to semantic analysis, demonstrating an important difference between OSM and other visual phenomena, such as the attentional blink, in which semantic processing is independent of awareness.     

Neuroaffective processing in criminal psychopaths: brain event-related potentials reveal task-specific anomalies

This study aimed to confirm neuroaffective processing deficits in psychopaths by measuring late brain event-related potential (ERP) components and behavior in groups of psychopathic and nonpsychopathic inmates of a Singaporean prison while they performed two tasks. In a Categorization task, affective stimuli were task-relevant and required focused attention, while in a Vigilance task, affective pictures were presented in the background while participants discriminated vertical from oblique lines. Psychopaths showed differences in late positive ERPs that were sensitive to affective stimulus properties (valence and arousal) in the Categorization, but not in the Vigilance task, suggesting that only under conditions of focused attention did psychopaths show a neuroaffective processing deficit. In the Categorization task, psychopaths also showed a significantly larger prefrontal negative ERP (N350) whose amplitude correlated positively with the behavioral facet of psychopathy. In the Vigilance task, psychopaths both missed more targets and showed significantly smaller target-evoked parietal ERPs when viewing arousing pictures, suggesting their attentional focus was disrupted by the affective background.     

Gender differences in memory processing: evidence from event-related potentials to faces

This study investigated gender differences on memory processing using event-related potentials (ERPs). Behavioral data and ERPs were recorded in 16 males and 10 females during a recognition memory task for faces. The behavioral data results showed that females performed better than males. Gender differences on ERPs were evidenced over anterior locations and involve the modulation of two spatially and temporally distinct components. These results are in general accordance with the view that males and females differ in the cognitive strategies they use to process information. Specifically, they could differ in their abilities to maintain information over interference and in the processing of the intrinsic contextual attributes of items, respectively, associated with the modulation of two anterior components. These interpretations lend support to the view that processing in females entails more detailed elaboration of information content than in males. Processing in males is more likely driven by schemas or overall information theme.     

工作记忆负荷对反馈加工过程的影响:来自脑电研究的证据

个体对行为后反馈结果的加工在学习和环境适应方面有重要意义,工作记忆负荷(working memory load,WM load)如何影响反馈加工过程尚不清楚。采用双任务范式,设置基线、低WM load、高WM load三种条件,结合ERP技术对这一问题进行探究。发现RewP (reward positivity,奖赏正波)对效价敏感,而不受WM load条件影响;Theta震荡的正、负反馈差异波在高WMload条件下比在低WM load条件下小。结果支持等级强化学习-前扣带回理论(HRL-ACC, hierarchical reinforcement learning theory of anterior cingulate cortex)对于RewP和theta震荡的观点:RewP反映了反馈效价评估功能, theta震荡反映了认知控制功能,并且WM load选择性影响了ACC的认知控制功能而不是反馈效价评估功能。     

Effects of grammatical categories on children's visual language processing: Evidence from event-related brain potentials

This study examined how school-aged children process different grammatical categories. Event-related brain potentials elicited by words in visually presented sentences were analyzed according to seven grammatical categories with naturally varying characteristics of linguistic functions, semantic features, and quantitative attributes of length and frequency. The categories included nouns, adjectives, verbs, pronouns, conjunctions, prepositions, and articles. The findings indicate that by the age of 9-10 years, children exhibit robust neural indicators differentiating grammatical categories; however, it is also evident that development of language processing is not yet adult-like at this age. The current findings are consistent with the hypothesis that for beginning readers a variety of cues and characteristics interact to affect processing of different grammatical categories and indicate the need to take into account linguistic functions, prosodic salience, and grammatical complexity as they relate to the development of language abilities.     

Visual event-related potentials of dogs: a non-invasive electroencephalography study

Previously, social and cognitive abilities of dogs have been studied within behavioral experiments, but the neural processing underlying the cognitive events remains to be clarified. Here, we employed completely non-invasive scalp-electroencephalography in studying the neural correlates of the visual cognition of dogs. We measured visual event-related potentials (ERPs) of eight dogs while they observed images of dog and human faces presented on a computer screen. The dogs were trained to lie still with positive operant conditioning, and they were neither mechanically restrained nor sedated during the measurements. The ERPs corresponding to early visual processing of dogs were detectable at 75–100 ms from the stimulus onset in individual dogs, and the group-level data of the 8 dogs differed significantly from zero bilaterally at around 75 ms at the most posterior sensors. Additionally, we detected differences between the responses to human and dog faces in the posterior sensors at 75–100 ms and in the anterior sensors at 350–400 ms. To our knowledge, this is the first illustration of completely non-invasively measured visual brain responses both in individual dogs and within a group-level study, using ecologically valid visual stimuli. The results of the present study validate the feasibility of non-invasive ERP measurements in studies with dogs, and the study is expected to pave the way for further neurocognitive studies in dogs.     

Early processing of emotional faces in children with autism: An event-related potential study

Social deficits are one of the most striking manifestations of autism spectrum disorders (ASDs). Among these social deficits, the recognition and understanding of emotional facial expressions has been widely reported to be affected in ASDs. We investigated emotional face processing in children with and without autism using event-related potentials (ERPs). High-functioning children with autism (n = 15, mean age = 10.5 ± 3.3 years) completed an implicit emotional task while visual ERPs were recorded. Two groups of typically developing children (chronological age-matched and verbal equivalent age-matched [both ns = 15, mean age = 7.7 ± 3.8 years]) also participated in this study. The early ERP responses to faces (P1 and N170) were delayed, and the P1 was smaller in children with autism than in typically developing children of the same chronological age, revealing that the first stages of emotional face processing are affected in autism. However, when matched by verbal equivalent age, only P1 amplitude remained affected in autism. Our results suggest that the emotional and facial processing difficulties in autism could start from atypicalities in visual perceptual processes involving rapid feedback to primary visual areas and subsequent holistic processing.     

Spatiotemporal pattern of appraising social and emotional relevance: Evidence from event-related brain potentials

Social information is particularly relevant for the human species because of its direct link to guiding physiological responses and behavior. Accordingly, extant functional magnetic resonance imaging (fMRI) data suggest that social content may form a unique stimulus dimension. It remains largely unknown, however, how neural activity underlying social (versus nonsocial) information processing temporally unfolds, and how such social information appraisal may interact with the processing of other stimulus characteristics, particularly emotional meaning. Here, we presented complex visual scenes differing in both social (vs. nonsocial) and emotional relevance (positive, negative, neutral) intermixed with scrambled versions of these pictures to N = 24 healthy young adults. Event-related brain potentials (ERPs) to intact pictures were examined for gaining insight to the dynamics of appraisal of both dimensions, implemented within the brain. Our main finding is an early interaction between social and emotional relevance due to enhanced amplitudes of early ERP components to emotionally positive and neutral pictures of social compared to nonsocial content, presumably reflecting rapid allocation of attention and counteracting an overall negativity bias. Importantly, our ERP data show high similarity with previously observed fMRI data using the same stimuli, and source estimations located the ERP effects in overlapping occipitotemporal brain areas. Our novel data suggest that relevance detection may occur already as early as around 100 ms after stimulus onset and may combine relevance checks not only examining intrinsic pleasantness/emotional valence but also social content as a unique, highly relevant stimulus dimension.     

Aesthetic appreciation of poetry correlates with ease of processing in event-related potentials

Rhetorical theory suggests that rhythmic and metrical features of language substantially contribute to persuading, moving, and pleasing an audience. A potential explanation of these effects is offered by “cognitive fluency theory,” which stipulates that recurring patterns (e.g., meter) enhance perceptual fluency and can lead to greater aesthetic appreciation. In this article, we explore these two assertions by investigating the effects of meter and rhyme in the reception of poetry by means of event-related brain potentials (ERPs). Participants listened to four versions of lyrical stanzas that varied in terms of meter and rhyme, and rated the stanzas for rhythmicity and aesthetic liking. The behavioral and ERP results were in accord with enhanced liking and rhythmicity ratings for metered and rhyming stanzas. The metered and rhyming stanzas elicited smaller N400/P600 ERP responses than their nonmetered, nonrhyming, or nonmetered and nonrhyming counterparts. In addition, the N400 and P600 effects for the lyrical stanzas correlated with aesthetic liking effects (metered–nonmetered), implying that modulation of the N400 and P600 has a direct bearing on the aesthetic appreciation of lyrical stanzas. We suggest that these effects are indicative of perceptual-fluency-enhanced aesthetic liking, as postulated by cognitive fluency theory.     

An attentional-adaptation account of spatial negative priming: Evidence from event-related potentials

Negative priming (NP) refers to a slower response to a target stimulus if it has been previously ignored. To examine theoretical accounts of spatial NP, we recorded behavioral measures and event-related potentials (ERPs) in a target localization task. A target and distractor briefly appeared, and the participant pressed a key corresponding to the target’s location. The probability of the distractor appearing in each of four locations varied, whereas the target appeared with equal probabilities in all locations. We found that response times (RTs) were fastest when the prime distractor appeared in its most probable (frequent) location and when the prime target appeared in the location that never contained a distractor. Moreover, NP effects varied as a function of location: They were smallest when targets followed distractors in the frequent distractor location—a finding not predicted by episodic-retrieval or suppression accounts of NP. The ERP results showed that the P2, an ERP component associated with attentional orientation, was smaller in prime displays when the distractor appeared in its frequent location. Moreover, no differences were apparent between negative-prime and control trials in the N2, which is associated with suppression processes, nor in the P3, which is associated with episodic retrieval processes. These results indicate that the spatial NP effect is caused by both short- and long-term adaptation in preferences based on the history of inspecting unsuccessful locations. This article is dedicated to the memory of Edward E. Smith, and we indicate how this study was inspired by his research career.     

Interplay of emotional valence and concreteness in word processing: An event-related potential study with verbs

The functional locus of emotional valence in word processing remains an open question. In event-related potentials, emotion has been found to elicit an early posterior negativity (EPN), which is assumed to reflect attention catching by the words’ meaning. Previously, the EPN was modulated by word category with verbs exhibiting longer EPN latencies compared with other word categories. Here we examined whether concreteness, a semantic variable, influences emotion processing. Within a lexical decision task for verbs, emotional valence (positive, negative, and neutral) was orthogonally combined with concreteness (concrete and abstract). EPN onset was found already at 250 ms post-stimulus for concrete verbs, whereas it started 50 ms later for abstract verbs. Concreteness effects occurred after the start of main effects of emotion. Thus, the elicitation of the EPN seems to be based on semantic processes, with emotional valence being accessed before other semantic aspects such as concreteness of verbs.     

Tell me more: The effects of expressed interest on receptiveness during dialog

Two studies investigated the effect of expressed interest on individuals’ openness to opposing viewpoints and perceptions of debate counterparts. Participants in Study 1 engaged in an online conversation with a purported debate counterpart who did or did not express interest in the participants’ viewpoint by asking an elaboration question—that is, a question geared at soliciting additional information. Compared to control participants, participants who received a question rated their debate counterpart more favorably, were more willing to engage in future interaction with their counterpart, and acted in a more receptive manner. Study 2 tested the effects of instructions to prepare elaboration questions on listeners’ responses to a speaker offering counter-attitudinal arguments. Preparing questions caused participants to be more open to the idea of having a conversation with the speaker, to make more positive attributions about typical proponents of the speaker’s viewpoint, and to judge the conclusions of the speech as more valid. Theoretical and practical implications of this research are discussed.     

Effects of temporal trial-by-trial cuing on early and late stages of auditory processing: Evidence from event-related potentials

Temporal-cuing studies show faster responding to stimuli at an attended versus unattended time point. Whether the mechanisms involved in this temporal orienting of attention are located early or late in the processing stream has not been answered unequivocally. To address this question, we measured event-related potentials in two versions of an auditory temporal cuing task: Stimuli at the uncued time point either required a response (Experiment 1) or did not (Experiment 2). In both tasks, attention was oriented to the cued time point, but attention could be selectively focused on the cued time point only in Experiment 2. In both experiments, temporal orienting was associated with a late positivity in the timerange of the P3. An early enhancement in the timerange of the auditory N1 was observed only in Experiment 2. Thus, temporal attention improves auditory processing at early sensory levels only when it can be focused selectively.