参考选择影响情绪加工相关的ERPs

研究采用情绪图片观看任务,考察双耳乳突参考、全脑平均参考和参考电极标准化技术（Reference electrode standardization technique, REST）对情绪相关ERP成分在波幅、统计功效、内部一致性方面的影响,以及参考选择对ERP伪迹剔除率的影响。结果显示,双耳乳突参考下颞区EPN的波幅显著小于REST和全脑平均参考下的结果,而在顶区LPP上表现出完全相反的结果。此外,双耳乳突和全脑平均参考下更可能检测到P2上负性和中性图片波幅间的差异,而REST和全脑平均参考下更可能检测到EPN的“正性偏向”效应。未来研究应结合以往文献和特定成分谨慎选择参考类型。     

The relationship between impulsiveness subtraits,trait anxiety,and visual N100 augmenting/reducing: A topographic analysis

The relationship between impulsiveness subtraits assessed by the Barratt Impulsiveness Scale (BIS-10), the trait anxiety subscale of the State-Trait Personality Inventory (STPI), and the topographic distribution of visual N100 augmenting/reducing (AR) was examined. Topographic event-related potential (ERP) data were collected from an array of 14 electrodes covering the left side of the head while subjects counted the total number of light flashes presented at two different but equiprobable intensities. Principal components analysis of the ERP data yielded a factor accounting for 13.9% of the total variance around the grand mean waveform that corresponded to the N100 wave clearly visible in the raw waveforms. For each subject by scalp locus combination, an AR score was computed by subtracting the factor score associated with the bright flashes from the factor score associated with the dim flashes. The correlations between AR scores and scores on the BIS-10 cognitive impulsiveness subscale were significant (P < 0.01) at all scalp loci with the exception of the extreme frontal and occipital poles. Correlations with the BIS-10 motor impulsiveness subscale had a similar scalp distribution. Correlations with the BIS-10 non-planning impulsiveness subscale were significant over the frontal third of the scalp, including the frontal pole. Trait anxiety was not significantly related at the 0.01 level to AR scores. Theoretical implications of these findings are discussed.     

Concreteness effects in the processing of Chinese words

The present study examined the relationship between word concreteness and word frequency using event-related potential (ERP) measurements during a lexical decision task. Potential effects of concreteness in the processing of verbs were also examined. ERPs were recorded from 119 scalp electrodes in 23 right-handed participants. The results showed that concrete nouns were associated with a more negative ERP than abstract nouns at 200-300 and 300-500 ms after stimulus onset, regardless of word frequency. Between 300 and 500 ms, concrete nouns and abstract nouns produced differentiated scalp distributions, respectively. In terms of verbs, concreteness only produced small difference in ERP primarily in the central-parietal sites of the left hemisphere.     

Selective attention to the color and direction of moving stimuli: Electrophysiological correlates of hierarchical feature selection

Event-related brain potentials (ERPs) were recorded from subjects who attended to pairs of adjacent colored squares that were flashed sequentially to produce a perception of movement. The task was to attend selectively to stimuli in one visual field and to detect slower moving targets that contained the critical value of the attended feature, be it color or movement direction. Attention to location was reflected by a modulation of the early P1 and N1 components of the ERP, whereas selection of the relevant stimulus feature was associated with later selection negativity components. ERP indices of feature selection were elicited only by stimuli at the attended location and had distinctive scalp distributions for features mediated by “ventral” (color) and “dorsal” (motion) cortical areas. ERP indices of target selection were also contingent on the prior selection of location but initially did not depend on the selection of the relevant feature. These ERP data reveal the timing of sequential, parallel, and contingent stages of visual processing and support early-selection theories of attention that stipulate attentional control over the initial processing of stimulus features.     

Event-related brain potentials to grammatical errors and semantic anomalies

Event-related brain potentials (ERPs) were recorded while subjects silently read several prose passages, presented one word at a time. Semantic anomalies and various grammatical errors had been inserted unpredictably at different serial positions within some of the sentences. The semantically inappropriate words elicited a large N400 component in the ERP, whereas the grammatical errors were associated with smaller and less consistent components that had scalp distributions different from that of the N400. This result adds to the evidence that the N400 wave is more closely related to semantic than to grammatical processing. Additional analyses revealed that different ERP configurations were elicited by open-class (“content”) and closed-class (“function”) words in these prose passages.     

A three-electrode system for EKG recording and aversive shock

The use of three electrodes to produce digitizable EKG’s and to deliver shocks to the tail of the monkey is described. Cardiac signals are taken from a head electrode and a “ground” tail electrode. Shock is administered through a “hot” tail electrode and the “ground” tail electrode.     

The Sounds of Sentences: Differentiating the Influence of Physical Sound,Sound Imagery,and Linguistically Implied Sounds on Physical Sound Processing

Both the imagery literature and grounded models of language comprehension emphasize the tight coupling of high-level cognitive processes, such as forming a mental image of something or language understanding, and low-level sensorimotor processes in the brain. In an electrophysiological study, imagery and language processes were directly compared and the sensory associations of processing linguistically implied sounds or imagined sounds were investigated. Participants read sentences describing auditory events (e.g., “The dog barks”), heard a physical (environmental) sound, or had to imagine such a sound. We examined the influence of the 3 sound conditions (linguistic, physical, imagery) on subsequent physical sound processing. Event-related potential (ERP) difference waveforms indicated that in all 3 conditions, prime compatibility influenced physical sound processing. The earliest compatibility effect was observed in the physical condition, starting in the 80–110 ms time interval with a negative maximum over occipital electrode sites. In contrast, the linguistic and the imagery condition elicited compatibility effects starting in the 180–220 ms time window with a maximum over central electrode sites. In line with the ERPs, the analysis of the oscillatory activity showed that compatibility influenced early theta and alpha band power changes in the physical, but not in the linguistic and imagery, condition. These dissociations were further confirmed by dipole localization results showing a clear separation between the source of the compatibility effect in the physical sound condition (superior temporal area) and the source of the compatibility effect triggered by the linguistically implied sounds or the imagined sounds (inferior temporal area). Implications for grounded models of language understanding are discussed.     

Event-related potentials and the semantic matching of pictures

Event-related potentials (ERPs) were recorded from one midline and three pairs of lateral electrodes while subjects determined whether pairs of sequentially presented pictures were semantically associated. The ERPs evoked by the second picture of each pair differed as a consequence of whether it was associated with its predecessor, such that ERPs to nonassociated pictures were more negative-going than those to associated items. These differences resulted from the modulation of two ERP components, one frontally distributed and centered on an N300 deflection, the other distributed more widely over the scalp and encompassing an N450 deflection. The modulation of N450 is interpreted as further evidence that the "N400" ERP component is sensitive to semantic relationships between nonverbal stimuli. The earlier N300 effects, which do not appear to occur when ERPs are evoked by semantically primed and unprimed words, could suggest that the semantic processing of pictorial stimuli involves neural systems different from those associated with the semantic processing of words.     

Event-related potential data acquisition on the Apple II+/IIe

Event-related potential (ERP) research is a valuable technique for understanding neural mechanisms underlying cognition. With few exceptions, this research has used minicomputer-based data-acquisition systems, thus limiting ERP research to labs with large computers. The hardware and software presented here allow the Apple II+ or Apple IIe microcomputers to present stimuli and collect data from as many as three electrode sites. A fourth electrode site may be used to monitor eyeblinks and allows the exclusion of those trials in which an eyeblink occurs. After the data are collected and averaged, they are stored by subject, task, and electrode on disk where they subsequently may be displayed, analyzed, or downloaded to a mainframe computer.     

猜谜作业中顿悟的ERP效应

采用事件相关电位(ERP)探索问题解决过程中顿悟的神经机制。以猜谜作业为实验程序,对“有顿悟”和“无顿悟”答案引发的脑电分别进行叠加和平均,并将二者相减（有顿悟-无顿悟）得到差异波。在250~500 ms “有顿悟”比“无顿悟”的ERP波形有一个更加负性的偏移,在差异波中,这个负成分的潜伏期约为380 ms（N380）。地形图和电流密度图显示,N380在额中央区活动最强。偶极子源定位分析结果显示,N380可能起源于扣带前回。因此,N380可能反映顿悟问题解决过程中思维定势的突破。     

Moral Realism,Social Construction,and Realism,Social Construction,and Communal Ontology

The paper examines two forms of naturalistic moral realism, “Microstructure realism” (MSR) and “Reason realism” (RR). The latter, as we defend it, locates the objectivity of moral facts in socially constructed reality, but the former, as exemplified by David Brink’s model of naturalistic moral realism, secures the objectivity of moral facts in their micro-structure and a nomic supervenience relationship. We find MSR’s parity argument for this account of moral facts implausible; it yields a relationship between moral facts and their natural-scientific constitution that has a queer, slapped-together quality. We argue that the relationship needs to be spelled out by a process of social construction, involving collective intentionality and constitutive rules. We explain how our constructivist model of RR differs from a form of it defended by Michael Smith (1994), which analyzes moral facts by reference not to construction but rather to a hypothetical situation of full rationality. We agree with Smith, as against Bernard Williams, that a rational agent may have reasons for acting that go beyond the agent’s “subjective motivational set,” but we locate such reasons by reference to the agent’s membership in an actual community, and we explore the prospects for moral objectivity given this constraint on moral reasons.     

Reading the writing in the margins: dysfunction,disjunction, disgust,and the bodies of others

ABSTRACT

Intersex’s representation as “border case,” explored via six fictional treatments of unusually sexed bodies, echoes the ways “atypical” and “marginal” sex and sexuality receive attention to defer focus on that never queried because it seems so ordinary. Across the novels, the purported otherness of the intersex character highlights the dysfunctionality of those around them. In this way, dysfunction, disjunction, and disgust exist across the relationships and dynamics surrounding the scapegoated identity and are a means to avoid the hard work of critical self-reflection on the parts of those who do not usually deem themselves “other.” If the supporting characters in all these novels are guilty of failing fully to explore their own marginality, the same has frequently happened with religious bodies’ attitudes to intersex, and this is discussed with reference to accounts of intersex in Judaism and Islam, and tensions surrounding the casting out of sexual “violators” in one Christian tradition.     

Visual asymmetry revisited: Mind wandering preferentially disrupts processing in the left visual field

An emerging theory proposes that visual attention operates in parallel at two distinct time scales – a shorter one (<1 s) associated with moment-to-moment orienting of selective visuospatial attention, and a longer one (>10 s) associated with more global aspects of attention-to-task. Given their parallel nature, here we examined whether these comparatively slower fluctuations in task-related attention show the same visual field asymmetry – namely, a right visual field bias – as often reported for selective visual–spatial attention. Participants performed a target detection task at fixation while event-related potentials (ERP) time-locked to task-irrelevant visual probes presented in the left and right visual fields were recorded. At random intervals, participants were asked to report whether they were “on-task” or “mind wandering”. Our results demonstrated that sensory attenuation during periods of “mind wandering” relative to “on-task”, as measured by the visual P1 ERP component at electrodes sites contralateral to the stimulus, was only observed for probes presented in the left visual field. In contrast, the magnitude of sensory gain in the right visual field was insensitive to whether participants were “on-task” or “mind wandering”. Taken together, our results support the notion that task-related attention at longer time scales and spatial attention at shorter time scales affect the same underlying mechanism in visual cortex.     

The ERP signature of the contextual diversity effect in visual word recognition

Behavioral experiments have revealed that words appearing in many different contexts are responded to faster than words that appear in few contexts. Although this contextual diversity (CD) effect has been found to be stronger than the word-frequency (WF) effect, it is a matter of debate whether the facilitative effects of CD and WF reflect the same underlying mechanisms. The analysis of the electrophysiological correlates of CD may shed some light on this issue. This experiment is the first to examine the ERPs to high- and low-CD words when WF is controlled for. Results revealed that while high-CD words produced faster responses than low-CD words, their ERPs showed larger negativities (225–325 ms) than low-CD words. This result goes in the opposite direction of the ERP WF effect (high-frequency words elicit smaller N400 amplitudes than low-frequency words). The direction and scalp distribution of the CD effect resembled the ERP effects associated with “semantic richness.” Thus, while apparently related, CD and WF originate from different sources during the access of lexical-semantic representations.     

Bootstrap assessment of the reliability of maxima in surface maps of brain activity of individual subjects derived with electrophysiological and optical methods

Surface maps of brain activity can be obtained with electrophysiological and optical recordings. However, there are no established methods for determining the reliability of maps of brain activity across subject groups or across tasks within the same subject. In this paper, we use bootstrapping to establish the reliability of the locations of maxima in maps of surface brain activity of individual subjects obtained with ERP and optical (EROS) recordings and report sample analyses for two data sets. Bootstrapping is a nonparametric method for estimating statistical accuracy from the data in a single sample. The distribution of the statistic of interest is estimated by constructing “bootstrap samples” from a pool of all available cases (with replacement). Many “bootstrap replications” are obtained by calculating the statistic of interest for each sample. In the case of brain activity, many (e.g., 10,000) amplitude distributions can be derived from the data of an individual subject. Frequency counts are then computed for each recording location to establish how many times that location corresponds to a maximum. The value obtained in this fashion represents an estimate of the reliability of the observation.     

不同程度吸烟者内隐态度测量范式下的ERP研究

采用内隐联想测验的WIAT范式研究不同程度吸烟者的内隐态度,并用ERP技术探讨吸烟者相容与不相容任务的脑内时程变化。WIAT结果发现,只有程度深组对吸烟持明显消极态度。ERP结果表明,在不相容任务中程度深组诱发了比程度浅组更大的P2,说明程度深组对与积极相联的吸烟词早期注意增强。同时程度深组的不相容任务诱发了比相容任务更大的LPC,提示程度深组晚期对吸烟词有正性情绪加工。     

时间知觉的注意调节：一项ERP研究

采用双任务实验范式探讨时间知觉注意调节的动态过程。通过指导语使被试按照比例将注意分配到声音刺激的时间属性与音调属性上,形成对时间因素不同注意程度的五种注意条件,同时记录反应时、错误率和事件相关电位数据。对峰值分析发现,P2注意条件主效应不显著,但多重比较时T（只注意时间）与P（只注意音调）条件差异显著;对CNV平均波幅分析,发现注意条件主效应显著,随着分配在时间属性上的注意的减少,其波幅逐渐降低;对T与P条件的差异波地形图分析发现,波幅最大的区域位于额叶、中央区和顶叶;该差异波的偶极子定位于辅助运动区（额上回、额中回）和顶下小叶。以上结果表明,P2阶段存在时间信息加工;CNV反映时间知觉的注意调节,时间知觉中存在控制加工应该以CNV的出现为指标;辅助运动区可能为时间知觉的核心成分,具有跨通道效应;顶下小叶也与对时间的注意有关,但并不是特异性的。本研究不支持Lewis提出的 “自动”与“认知控制”计时系统理论中 “秒”为两系统分界点以及辅助运动区只属于“自动计时系统”的观点     

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

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

“Just do it… before you talk yourself out of it”: the self-talk of adults thinking about physical activity

ObjectivesLittle is known about what adults are thinking about and doing for health-promoting physical activity (PA). We examined the PA levels of middle-aged (40–55 years) and older men and women (56+) as well as their intentions for future activity.MethodsRandom telephone surveys stratified for age, gender and geographic location assessed the weekly PA and plans for exercise among 40 adults.ResultsNumerical data showed that activity patterns were age-determined and gender-patterned with adults aged 40–55 expending far more energy at both work and leisure-time PA than adults aged 56+. Self-talk strategies occurred among 88% of the respondents but a key strategy used by active people was to ignore activity self-talk and ‘just do it’ lest they talk themselves out of exercising.ConclusionsInactive people already know that keeping active is important to their health and still do not participate. The group to target with positive triggering messages, assistance in getting started and reminders are those who already want to be more active but have not got a regular pattern established. Future research is needed to explore the impact of various kinds of social cueing. Messages such as, “Just do it” or “Don’t think about it” may be all that is needed to trigger adults who are already seriously contemplating how to increase their PA.     

Maturation of the long-latency auditory ERP: step function changes at start and end of adolescence

The auditory event-related potential (ERP) is obtained by averaging electrical impulses recorded from the scalp in response to repeated stimuli. Previous work has shown large differences between children, adolescents and adults in the late auditory ERP, raising the possibility that analysis of waveform shape might be useful as an index of brain maturity. We reanalysed auditory ERPs from samples previously described by Albrecht, von Suchodoletz and Uwer (2000) and Uwer, Albrecht and von Suchodoletz (2002), using the intraclass correlation (ICC) as a global measure of similarity of an individual's waveform to a grand average comparison waveform for each age band. Three developmental periods were clearly distinguished: 5 to 12 years, 13 to 16 years, and adulthood. However, within each of these periods, there was no evidence of any developmental progression with age.