An event-related potential study of the revelation effect

Event-related potentials (ERPs) were recorded during a verbal recognition memory task in order to investigate whether changes in familiarity are part of the explanation for the revelation effect. For half of the test words, participants solved an anagram prior to making the old/new recognition judgment. A revelation effect was obtained: When test words were preceded by the anagram task, a higher probability of an old response was associated with the items than was otherwise the case. The ERPs recorded time-locked to the onset of the test words were separated according to old/new status andthe presence/absence of the anagram task. The ERP index of familiarity was of lower amplitude for both old and new items that were preceded by the anagram task. These findings are consistent with the view that part of the explanation for the revelation effect is a reduction in the familiarity of the critical test items.     

An event-related brain potential study of inhibition of return

Event-related brain potentials (ERPs) were recorded during two spatial-cuing experiments using nonpredictive cues. Our primary goal was to determine the electrophysiological consequences of inhibition of return (IOR). At long (> 500 msec) cue-target intervals, subjects responded more slowly to targets that appeared at or near the cued location, relative to targets that appeared on the opposite side of fixation from the cue. This behavioral IOR effect was associated with cue-validity effects on several components of the target-elicited ERP waveforms. The earliest such effect was a smaller occipital P1 on valid-cue trials, which we interpret as a P1 reduction. The P2 component was also smaller on valid-cue trials, indicating that nonpredictive spatial cues influence multiple stages of information processing at long cue-target intervals. Both of these effects were observed when sensory interactions between cue and target were likely to be negligible, indicating that they were not caused by sensory refractoriness. A different effect of cue validity, the posterior negative difference, was found when sensory interactions were likely to be greatest, indicating that it could arise from sensory refractoriness.     

汉语名-动兼类效应的神经机制研究

文章运用ERP技术,考察了汉语名-动兼类词在语法语境下的脑神经机制。实验结果显示,名-动兼类词与非兼类的名词和动词所诱发的P600成分没有显著差异,只有在动词语境下,名-动兼类词才在额区和中央区诱发出一个更小的N400成分;与动词语境中的名-动兼类词相比,名词语境中的名-动兼类词诱发出更大的P600成分,这与非兼类名词、动词相互分离的神经机制相同。根据实验结果认为,与相应的非兼类名词和动词相比,从语法角度划分的汉语名-动兼类词没有特异的脑神经机制。     

Updating of context in working memory: An event-related potential study

Flexible control of behavior depends on the representation, maintenance, and updating of context information in working memory, which is thought to rely on the prefrontal cortex (PFC). However, in contrast to maintenance, the dynamics of context activation and updating have not been well studied. To identify neural signals associated with context updating, we compared event-related potentials associated with cues that did or did not provide task-relevant context information. The earliest effect of context was detected 200 msec following cue onset and had a scalp topography consistent with a generator in the PFC. Subsequent effects of context were detected at 400-700 msec following cue onset (P3b), with a broad scalp distribution spanning posterior areas, and during the final 300 msec preceding the target, with a probable generator in the medial frontal cortex. We propose that the effect of context on P2 is consistent with the onset of context updating in the PFC. Subsequent components may be indicative of activation of task-relevant posterior regions and context maintenance.     

网球运动专长对深度运动知觉影响的ERP研究

结合专家-新手范式与ERP技术,研究网球运动专长对个体深度运动知觉产生的影响。通过记录网球专家和新手各19名进行深度运动模式判断时的行为和ERP数据,比较两组个体深度运动知觉的行为反应差异和脑电特征。结果显示,网球专家组深度运动知觉的判断准确率高于新手组;新手组在球体靠近时P1(PO7点)的潜伏期比球体远离时的潜伏期长,专家组无显著性差异;专家组在球体靠近时的P2(Oz点)成分潜伏期长于球体远离时的潜伏期。结果表明,网球运动专家的深度运动知觉能力在准确性上较新手高;运动专长效应与选择性注意资源的调用以及模式识别有关;枕区P2成分可作为深度运动知觉的评价指标。     

The influence of spatial representation on valence judgements: An event-related potential study

The present study used event-related potentials (ERPs) to explore the nature of space-valence congruency effects. We presented participants with up or down arrows at the centre of the screen and then asked participants to identify whether the following target words had the emotional valence. The target words included positive emotional words (e.g., “happy” and “delight”), negative emotional words (e.g., “sad” and “depressive”) and neutral words (e.g., “history” and “country”). Behavioural data showed that the positive targets were identified faster when they are primed by up arrows than when primed by down arrows, whereas the negative targets were identified faster when they are primed by down arrows than when primed by up arrows. The ERP analysis showed larger P2 amplitudes were found in the congruent condition (i.e., the positive targets following up arrows or the negative targets following down arrows) than in the incongruent condition (i.e., the positive targets following down arrows or the negative targets following up arrows). Furthermore, larger N400 amplitudes were found in the incongruent condition compared with the congruent condition. Moreover, larger LPC amplitudes were found in the congruent condition compared with the incongruent condition. Therefore, in addition to replicating the space-valence congruency effects in a neutral/emotional judgement task, our study also extended previous studies by showing that spatial information modulates the processing of the emotional words at multiple stages.     

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.     

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.     

Early perception of written syllables in French: An event-related potential study

The present study examined whether written syllable units are perceived in first steps of letter string processing. An illusory conjunction experiment was conducted while event-related potentials were recorded. Colored pseudowords were presented such that there was a match or mismatch between the syllable boundaries and the color boundaries. The results showed that congruent stimuli for which the syllable and color boundaries coincided produced a greater positive-going waveform than incongruent stimuli for which the syllable and color boundaries did not coincide. This syllable–color congruency effect was observed to occur both prior to 100 ms, and in a time window commencing at 150 ms. This finding suggests that syllable units are perceived in the initial steps of French visual word processing. Moreover, this study underlines the specificity of the illusory conjunction paradigm as a relevant and powerful tool of investigation of sublexical units that are automatically evoked from word perception.     

Protective role of educational level on episodic memory aging: An event-related potential study

The aim of the present experiment was to investigate whether educational level could modulate the effect of aging on episodic memory and on the electrophysiological correlates of retrieval success. Participants were divided into four groups based on age (young vs. older) and educational level (high vs. low), with 14 participants in each group. Event-related potentials (ERP) were recorded while participants performed a word-stem cued-recall task. Age-related memory deficits were greater for the less educated individuals. Age differences in the ERP old/new effects were also modulated by the level of education. This study demonstrated that the effects of age on episodic memory and ERP correlates of retrieval success are smaller in participants with high educational levels than those with lower levels. These findings provide support for the reserve hypothesis and highlight the need to consider individual differences when studying cognitive and cerebral changes in aging.     

Multiple sources of positive- and negative-priming effects: An event-related potential study

Event-related potential correlates of positive priming (PP) and negative priming (NP) were investigated in order to further elucidate the cognitive mechanisms involved. Thirty-six participants performed both an identity- and a location-based priming task. Repeating the target stimulus/location from the immediately preceding display produced behavioral PP. With localization, but not with identification, behavioral NP was observed when the target stimulus/location matched the preceding distractor stimulus/location. Smaller P300 amplitude accompanied identity-based PP, suggesting persisting target-specific activation. The lateralized readiness potential, an index of correct/incorrect response activation, indicated persisting central motor activation as another source of PP. Both location-based PP and NP were accompanied by reduced P1/N1 and P300 amplitudes, pointing to the involvement of inhibition of return in location-based priming. The results support the view that multiple brain processes underlie behavioral priming.     

Investigating letter recognition in the brain by varying typeface: An event-related potential study

We aimed to investigate the contributions of visual letter form and abstract letter identity to the time course of letter recognition, by manipulating the typeface (i.e. font) in which letters were presented. Twenty-six adult participants completed a modified one-back task, where letters where presented in easy-to-read typefaces (“fluent” letter stimuli) or difficult-to-read typefaces (“disfluent” letter stimuli). Task instructions necessitated that participant’s focus on letter identity not visual letter form. Electroencephalography was collected and event-related potentials (ERPs) were calculated relative to letter stimuli. It was found that typeface affected both early-mid (N1 amplitude and P2–N2 amplitude and latency) and late processing (450–600 ms), thereby including time points whereby it is theorised that abstract identity is extracted from visual letter form (that is, 300 ms post-stimulus). Visual features of the letter therefore affect its processing well beyond the currently theorised point at which abstract information is extracted; which could be explained by a feedback loop between abstract letter representations and lower-level visual form processing units, which is not included in current cognitive reading models.     

Mental rotation: An event-related potential study with a validated mental rotation task

Event-related potentials (ERPs) were recorded while subjects performed a validated mental rotation task, taken from the cognitive psychology literature. These ERPs show a late posterior negativity relative to a baseline condition requiring all of the same perceptual and cognitive processes except for the mental rotation itself. Our tentative identification of this posterior negativity with mental rotation is further supported by the finding that it varies systematically with the amount of mental rotation required on a trial by trial basis in the experimental task. We conclude that this late negativity is an ERP marker of the mental rotation process, and that this process engages primarily posterior brain regions.     

Recognition memory for object form and object location: An event-related potential study

In this study, the processes associated with retrieving object forms and object locations from working memory were examined with the use of simultaneously recorded event-related potential (ERP) activity. Subjects memorized object forms and their spatial locations and made either object-based or location-based recognition judgments. In Experiment 1, recognition performance was higher for object locations than for object forms. Old responses evoked more positive-going ERP activity between 0.3 and 1.8 sec poststimulus than did new responses. The topographic distribution of these old/new effects in the P300 time interval was task specific, with object-based recognition judgments being associated with anteriorly focused effects and location-based judgments with posteriorly focused effects. Late old/new effects were dominant at right frontal recordings. Using an interference paradigm, it was shown in Experiment 2 that visual representations were used to rehearse both object forms and object locations in working memory. The results of Experiment 3 indicated that the observed differential topographic distributions of the old/new effects in the P300 time interval are unlikely to reflect differences between easy and difficult recognition judgments. More specific effects were obtained for a subgroup of subjects for which the processing characteristics during location-based judgments presumably were similar to those in Experiment 1. These data, together with those from Experiment 1, indicate that different brain areas are engaged in retrieving object forms and object locations from working memory. Further analyses support the view that retrieval of object forms relies on conceptual semantic representation, whereas retrieving object locations is based on structural representations of spatial information. The effects in the later time intervals may play a functional role in post-retrieval processing, such as recollecting information from the study episode or other processes operating on the products of the retrieval process, and presumably are mediated by right frontal cortical areas. The results support the view of functionally dissociable object and spatial visual working memory systems.     

The organization of multidimensional selection on the basis of color and shape: An event-related brain potential study

In this paper, we examine whether color and shape, tied to a single object in space, (1) are identified and selected in series or in parallel, (2) are identified and selected in a dependent, self-terminating manner or in an independent and exhaustive manner, and (3) are conjoined by a feature integration process before or only after an initial stage of separate attribute analyses has finished. We measured response time and the selection negativity (SN) derived from event-related brain potentials when participants responded to a unique conjunction of color and shape in a go/no-go target detection task. The discriminability of the color and the shape of the conjunction was manipulated in three conditions. When color and shape were easy to discriminate, the SNs to color and shape started at the same time. When one attribute was less discriminable, the SN to that attribute started later, but not the SN to the complementary attribute. This suggests that color and shape are identified and selected in parallel. In all three discriminability conditions, the SNs to color and shape were initially independent but later interacted. This suggests that color and shape are initially selected independently and exhaustively, after which their conjunction is analyzed. The SN to local shape features started later than that to the conjunction of color and global shape features, which suggests that feature integration can start before the analyses of the separate attributes have finished.     

抑郁倾向对个体情绪调节目标的影响——来自事件相关电位的证据

目前抑郁症情绪失调的研究主要关注策略的选择和应用, 但是对于情绪调节目标是否异常及其背后的电生理基础尚不清楚。情景选择是成熟的情绪反应产生之前运用的一种调节策略, 可以反映情绪调节目标。本研究要求抑郁倾向被试与控制组被试观看并选择快乐、中性和悲伤场景图片, 同时记录事件相关电位(ERP)和主观情绪偏好。结果发现, 抑郁倾向组悲伤图片的LPP波幅显著小于健康控制组, 并更多地选择再次观看悲伤图片。此外, 抑郁倾向组对于悲伤情绪的偏好显著增加, 对快乐情绪的偏好则显著降低。结果提示抑郁倾向个体对快乐刺激的趋近动机和对悲伤刺激的回避动机都降低, 从而使得抑郁倾向被试的情绪调节目标为更多地体验到悲伤。     

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.     

The gradient of spatial auditory attention in free field: An event-related potential study

Young adult subjects attended selectively to brief noise bursts delivered in free field via a horizontal array of seven loudspeakers spaced apart by 9° of angle. Frequent “standard” stimuli (90%) and infrequent “target/deviant” stimuli (10%) of increased bandwidth were delivered at a fast rate in a random sequence equiprobably from each speaker. In separate runs, the subjects’ task was to selectively attend to the leftmost, center, or rightmost speaker and to press a button to the infrequent “target” stimuli occurring at the designated spatial location. Behavioral detection rates and concurrently recorded event-related potentials (ERPs) indicated that auditory attention was deployed as a finely tuned gradient around the attended sound source, thus providing support for gradient models of auditory spatial attention. Furthermore, the ERP data suggested that the spatial focusing of attention was achieved in two distinct stages, with an early more broadly tuned filtering of inputs occurring over the first 80–200 msec after stimulus onset, followed by a more narrowly focused selection of attended-location deviants that began at around 250 msec and closely resembled the behavioral gradient of target detections.