An ERP investigation of item-scene incongruity at encoding on subsequent recognition

The aim of the present study was to investigate how item-scene incongruity at encoding influences subsequent item recognition and the associated event-related potential (ERP) old/new effects. Participants (N = 26) studied pictures showing an item in a scene, either in a congruent condition (e.g., a tent in a field) or an incongruent condition (e.g., a shower cabin in a field). Items were presented alone at test. Behavioral data revealed a benefit of incongruent information, with greater source memory performance but no significant effect on old/new recognition judgments. Longer response times for old compared to new items showed that participants not only evaluated the old-new status of objects during recognition, but also worked already on the scene context decision relative to the source memory judgment. An ERP incongruity effect was found at study, with greater N400 amplitude in the incongruent condition than the congruent condition. During recognition, the results provide evidence that item-scene incongruity at study increases the amplitude of ERP old/new effects. A mid-frontal N400 old/new effect was found in the early time window (300–500 ms), and a right frontal sub-component was modulated by item-scene incongruity at encoding. The modulation observed in the later time window (500–800 ms) confirmed previous studies showing that the parietal old/new effect reflects the retrieval of episodic contextual details. The present study shows that the magnitude of ERP old/new effects is sensitive to item-scene incongruity at encoding from the early time window in the right frontal region to the later retrieval processes.     

Repetition attenuates the influence of recency on recognition memory: Behavioral and electrophysiological evidence

Studies of recognition memory often demonstrate a recency effect on behavioral performance, whereby response times (RTs) are faster for stimuli that were previously presented recently as opposed to more remotely in the past. One account of this relationship between performance and presentation lag posits that memories are accessed by serially searching backward in time, such that RT indicates the self-terminating moment of such a process. Here, we investigated the conditions under which this serial search gives way to more efficient means of retrieving memories. Event-related potentials (ERPs) were recorded during a continuous recognition task, in which subjects made binary old/new judgments to stimuli that were each presented up to four times across a range of lags. Stimulus repetition and shorter presentation lag both gave rise to speeded RTs, consistent with previous findings, and we novelly extend these effects to a robust latency measure of the left parietal ERP correlate of retrieval success. Importantly, the relationship between repetition and recency was further elucidated, such that repetition attenuated lag-related differences that were initially present in both the behavioral and neural latency data. These findings are consistent with the idea that an effortful search through recent memory can quickly be abandoned in favor of relying on more efficient “time-independent” cognitive processes or neural signals.     

Psychological distance modulates the performance of the embodiment effect: Evidence from behavioral and ERP studies

Research on embodied cognition suggests the ubiquity of embodiment effects during interaction with the environment. However, construal level theory (CLT) holds that these effects could be moderated by the psychological distance between self and objects and are attenuated by higher‐level mental construal. The current research explored the “action‐evaluation” embodiment effect in the evaluation of words located at different spatial distances. Results showed that for “short‐distance” words, the response model conflicted with this embodiment effect slower reaction time and induced a larger P2 component than the opposite response model. However, evaluation of “long‐distance” words was not significantly influenced by the response model. The results are consistent with CLT and suggest that the action‐evaluation embodiment effect influences the coding and execution of evaluating actions, but only for stimuli at close psychological distance locations.     

Covert attention in touch: behavioral and ERP evidence for costs and benefits

To investigate the mechanism underlying tactile spatial attention, reaction times (RTs) and event-related potentials (ERPs) were recorded in response to mechanical stimuli delivered to the hands. At the start of each trial cues indicated either the correct (valid) or incorrect (invalid) tactile stimulus location or were uninformative (neutral). RT costs (suppression of invalid compared to neutral trials) were found to be larger than benefits (enhancement of valid compared to neutral trials). ERPs showed that costs and benefits contribute equally to attentional modulations of the somatosensory N140 component, whereas these were largely due to costs at longer latencies. These results differ from the pattern of attentional ERP modulations previously found for vision and audition, where costs precede benefits, and therefore suggest that the mechanisms of attentional selectivity in touch might be different from attentional processes in other modalities.     

ERP correlates of transposed-letter priming effects: the role of vowels versus consonants

One key issue for any computational model of visual-word recognition is the choice of an input coding scheme for assigning letter position. Recent research has shown that pseudowords created by transposing two letters are very effective at activating the lexical representation of their base words (e.g., relovution activates REVOLUTION ). We report a masked priming lexical decision experiment in which the pseudoword primes were created by transposing/replacing two consonants or two vowels while event-related potentials were recorded. The results showed a modulation of the amplitude at an early window (150–250 ms) and at the N400 component for vowels but not for consonant transpositions. In addition, the peak latencies were faster for transposed than replaced consonants. These results suggest that consonants and vowels play a different role during the process of visual word recognition. We examine the implications for the choice of an input coding scheme in models of visual-word recognition.     

The reliability of ERP components in the auditory oddball paradigm

Nineteen adolescents (average age 15 years, 3 months) were tested and retested using a standard 40 target, auditory oddball ERP paradigm across an interval of 1 year, 10 months to determine reliability of the ERP components, both in terms of intersubject stability and score agreement and in terms of trait (between-session reliability) versus state (within-session reliability). Significant trait stability was found for the N100, P200, and P300 latencies (r= .48, .51, and .74, respectively), and for P300 amplitude (r= .62), supporting the P300 as a reliable measure, with the stability required for group research but not necessarily for clinical applications. Discussion and examples illustrate the application of reliability information to the planning and evaluation of ERP paradigms.     

孤独症儿童面孔认知ERP的PrN170研究

目的：探讨孤独症儿童与普通儿童在面孔识别事件相关电位（ERP）的差异。方法：以中性表情的面孔以及物件照片为刺激材料,以儿童喜欢物件的照片作为靶刺激,采用32通道ERP仪,分别记录20名孤独症儿童与22名普通儿童的ERP,比较两类儿童在不同刺激下N170电位的前体（Pre—cursorN170,PrN170）成分。采用SPSS13．0进行数据处理分析。结果：孤独症儿童组按键任务反应时较普通儿童组长（P〈0．05）,正确率无差别（P〉0．05）;两组儿童在面孔刺激呈现后约220ms颞枕叶导联发现PrN170,两组问对于不同类型的图片刺激,PrN170电位波幅与潜伏期均未见差异（P〉0．05）。结论：孤独症儿童的面孔结构编码过程无显著异常。     

P1 and beyond: functional separation of multiple emotion effects in word recognition

Event-related potentials (ERPs) revealed effects of emotional meaning on word recognition at distinguishable processing stages, in rare cases even in the P1 time range. However, the boundary conditions of these effects, such as the roles of different levels of linguistic processing or the relative contributions of the emotional valence and arousal dimensions, remain to be fully understood. The present study addresses this issue by employing two tasks of different processing demands on words that orthogonally varied in their emotional valence and arousal. Effects of emotional valence in ERPs were evident from 100 ms after word onset and showed a task-insensitive processing advantage for positive words. Early posterior negativity (EPN) effects to high-arousing words were limited to the lexical decision task, corroborating recent reports that suggested that perceptual processing as reflected in the EPN might not be as automatic as previously assumed.     

Trial effects in single-trial ERP components and autonomic responses at very long ISIs

Single-trial data from autonomic and ERP measures were used to capture the rapidly decreasing initial responses characteristic of the orienting reflex (OR) to repeated stimuli. Stimulus–response patterns were compared to determine central analogues of autonomic indices of processes leading to the OR, and the OR itself. Participants were presented with 12 indifferent tones in an auditory dishabituation paradigm. Temporal principal component analysis (PCA) decomposed EOG-corrected ERP data for 16 subjects. Response patterns of ERPs, cardiac, and respiratory responses were compared to the phasic skin conductance response (SCR). SCR decremented over trials, recovered on the change trial, and dishabituated to the representation of the standard, meeting the formal definition of habituation required of the OR. The evoked cardiac response showed no trial effects. Respiratory pause (RP) decreased linearly over trials, recovering marginally on the change trial. Nine identifiable ERP components were extracted: P1, N1-3, N1-1, processing negativity (PN), P2, P3a, P3b, a novelty-sensitive P3 component (labelled HabP3), and the slow wave (SW). P3b and SW showed decrement over trials, but with no recovery, HabP3 showed decrement and increased response on the change trial, while the P1, N1 subcomponents, P2 and P3a were insensitive to novelty. Stimulus–response patterns of the RP and HabP3 suggest sensitivity to novelty processing, while the P1, N1-3, N-1, PN, P2, P3a and cardiac deceleration appear to mark processing prior to novelty, such as stimulus transient detection (cardiac deceleration) and/or intensity processing. This study supports predictions of preliminary process theory, demonstrating fractionation of 3 autonomic and 9 ERP components to novelty, and disconfirming the unitary nature of the OR.     

ERP indices of emotionality and semantic cohesiveness during recognition judgments

Event-related potentials (ERPs) were used to examine the impact of emotionality on false recognition. In Experiment 1, participants discriminated previously studied words from neutral and negatively valenced emotional foils. Emotional words elicited a more positive ERP than did neutral words and emotional foils were falsely recognized more often than neutral foils. In Experiment 2, the hypothesis that emotionality-based false recognition is due to the semantic cohesiveness of emotional words was tested by including a highly associated but emotionally neutral category (animals). It was emotional and not animal foils that elicited greater positivity in the ERP and increased false positive response. These data provide little support for semantic cohesiveness as the basis for false recognition effects, but are consistent with the view that the salience of emotional words can be falsely attributed to familiarity in the context of a recognition task.     

Negative life events and symptom resolution in pediatric abdominal pain patients

Investigated relation of negative life events (NLE) to initial symptom severity and symptom resolution at 3 months in 2 patient groups: (a) recurrent abdominal pain (RAP) without identifiable organic etiology, (b) abdominal pain with organic diagnosis. Symptoms assessed were abdominal pain, somatization symptoms, anxiety, depression. Number of NLE was positively correlated with anxiety and depression in both groups at clinic visit. NLE predicted resolution of abdominal pain for RAP patients only; RAP patients with more NLE prior to or following the clinic visit were more likely to maintain their abdominal pain. More NLE following clinic visit was associated with maintenance of anxiety and somatization symptoms at follow-up in RAP patients. Results suggest a measure of NLE is not useful in differential diagnosis of patients with and without organic findings, but is useful in predicting outcome in patients without organic findings.     

An ERP correlate of metrical stress in spoken word recognition.

Rhythmic properties of spoken language such as metrical stress, that is, the alternation of strong and weak syllables, are important in speech recognition of stress-timed languages such as Dutch and English. Nineteen subjects listened passively to or discriminated actively between sequences of bisyllabic Dutch words, which started with either a weak or a strong syllable. Weak-initial words, which constitute 12% of the Dutch lexicon, evoked more negativity than strong-initial words in the interval between P2 and N400 components of the auditory event-related potential. This negativity was denoted as N325. The N325 was larger during stress discrimination than during passive listening. N325 was also larger when a weak-initial word followed a sequence of strong-initial words than when it followed words with the same stress pattern. The latter difference was larger for listeners who performed well on stress discrimination. It was concluded that the N325 is probably a manifestation of the extraction of metrical stress from the acoustic signal and its transformation into task requirements.     

The role of the T3 molecular complex in antigen recognition and subsequent activation events

Monoclonal antibodies raised against human T lymphocytes have identified several cell surface structures that are intimately involved in T-cell function. Perhaps the most familiar is the structure labelled T3. First identified as an antigen five years ago, it is now known to be a complex of at least three molecular species that is found on all T lymphocytes. There seems little doubt that T3 is closely associated with the antigen receptor on these cells, but how? A new (and different) answer is proposed in each of the following articles.     

Interparental aggression and infant patterns of adrenocortical and behavioral stress responses

Drawing on emotional security theory, this study examined linkages between interparental aggression, infant self‐regulatory behaviors, and patterns of physiological and behavioral stress responses in a diverse sample of 735 infants residing in predominately low‐income, non‐metropolitan communities. Latent profile analysis revealed four classes of adrenocortical and behavioral stress‐response patterns at 7 months of age, using assessments of behavioral and cortisol reactivity to an emotion eliciting challenge, as well as global ratings of the child's negative affect and basal cortisol levels. The addition of covariates within the latent profile model suggested that children with more violence in the home and children who used less caregiver‐oriented regulation strategies were more likely to exhibit a pattern of high cortisol reactivity with moderate signs of distress rather than the average stress response, suggesting possible patterns of adaptation in violent households. © 2011 Wiley Periodicals,Inc. Dev Psychobiol 54: 685–699, 2012.     

Similarity dependency of the change in ERP component N1 accompanying with the object recognition learning

Performance during object recognition across views is largely dependent on inter-object similarity. The present study was designed to investigate the similarity dependency of object recognition learning on the changes in ERP component N1. Human subjects were asked to train themselves to recognize novel objects with different inter-object similarity by performing object recognition tasks. During the tasks, images of an object had to be discriminated from the images of other objects irrespective of the viewpoint. When objects had a high inter-object similarity, the ERP component, N1 exhibited a significant increase in both the amplitude and the latency variation across objects during the object recognition learning process, and the N1 amplitude and latency variation across the views of the same objects decreased significantly. In contrast, no significant changes were found during the learning process when using objects with low inter-object similarity. The present findings demonstrate that the changes in the variation of N1 that accompany the object recognition learning process are dependent upon the inter-object similarity and imply that there is a difference in the neuronal representation for object recognition when using objects with high and low inter-object similarity.     

An ERP study on the time course of phonological and semantic activation in Chinese word recognition

With the event-related potential (ERP) technique, we examined the time course of phonological and semantic activation in Chinese word recognition. Participants did a semantic judgment task and a homophone judgment task over the same set of word pairs. Each pair was of either high or low word frequency and the two words were either unrelated or related semantically or phonologically, i.e., being homophones. For high-frequency words, both the semantically related pairs in the homophone task and the homophonic pairs in the semantic task elicited ERP responses different from the unrelated control pairs in the N400 component but not any component earlier, suggesting a similar time course for semantic and phonological activation. For low-frequency words, the semantically related pairs in the homophone task were associated with a similar modulation of N400. However, compared to the unrelated controls, the homophonic pairs in the semantic task elicited a larger P200, a component implicated in phonological processing in the literature, and thus demonstrated a phonological activation earlier than semantic activation. The results showed that word frequency affects the time course of semantic and phonological activation suggesting that phonology is not invariably activated before semantics in Chinese word recognition.     

Brain potential correlates of face recognition: geometric distortions and the N250r brain response to stimulus repetitions

The N250r is an event-related potential that has been related to activation of image-independent representations of familiar faces during recognition. However, N250r also shows a degree of image specificity, with reduced activation across repetitions of different images of the same face compared to repetitions across the same image, suggesting a component that codes the visual overlap between two face images. This study investigated whether N250r is equally attenuated when horizontally or vertically stretched faces prime an unstretched image of the same face. The results confirm that N250r is larger across repetitions of the same face image than across different images of the same face. Despite this, N250r was equivalent for priming by the same face image and priming from stretched onto unstretched faces. This finding demonstrates that N250r does not simply reflect the superficial visual overlap between two face images and supports the notion that it is related to person recognition.     

An ERP study of cognitive architecture and the insertion of mental processes: Donders revisited

In his seminal paper, Donders proposed that Choice reaction time (RT) tasks differ from Go/No-go RT tasks only by the insertion of a response decision operation. We evaluated this possibility by comparing the time course of Laplacian-transformed ERPs, recorded over the primary (M1s) and supplementary motor areas (SMAs) in a Choice and in a Go/No-go task. Laplacian-transformed ERPs showed that a component that develops over the SMAs during the RT of Choice tasks vanishes in our Go/No-go task. This indicates that a process, absent in the Go/No-go task, was "inserted" in the Choice task. The Choice versus Go/No-go manipulation also modified the motor command: the activity recorded over M1s and the delay separating EMG onset from response completion depended on the nature of the task. This indicates that, although a process was inserted in the Choice task, it was not "purely" inserted, contrary to Donders' initial assumption.     

An ERP Examination of the Different Effects of Sleep Deprivation on Exogenously Cued and Endogenously Cued Attention

Background:

Behavior and neuroimaging studies have shown selective attention to be negatively impacted by sleep deprivation. Two unresolved questions are (1) whether sleep deprivation impairs attention modulation of early visual processing or of a later stage of cognition and (2) how sleep deprivation affects exogenously versus endogenously driven selective attention.

Study Objectives:

To investigate the time course and different effects of sleep deprivation on exogenously and endogenously cued selective attention.

Design:

Participants performed modified Attention Network Tests (ANTs) using exogenously and endogenously cued targets to index brain networks underlying selective attention. Target-locked event-related potentials (ERPs) were recorded as participants performed the Attention Network Tests on 2 days separated by 24 hours of total sleeplessness.

Participants:

Fourteen US Military Academy cadets and 12 US Army soldiers from the Ironhorse Brigade, Ft. Hood, Texas.

Measurement and Results:

For both Attention Network Tests, sleep deprivation led to slowed response times, decreased accuracy rates, a diminished positive P3 (450- to 550-ms) ERP component, and an enhanced P2 (312- to 434-ms) ERP component. In contrast, the parietal N1 (157- to 227-ms) ERP response was reduced with sleep deprivation for endogenously, but not exogenously, cued targets. These sleep deprivation-related effects occurred in the context of typical behavior and ERP patterns expected in a cued spatial-attention task.

Conclusions:

These findings suggest that as little as 24 hours of sleep deprivation affects both early and late stages of attention selection but affects endogenously driven selective attention to a greater degree than it does exogenously driven selective attention.

Citation:

Trujillo LT; Kornguth S; Schnyer DM. An ERP examination of the different effects of sleep deprivation on exogenously cued and endogenously cued attention.     

语音识别技术在咳嗽声音自动识别中的应用

目的 利用双门限法、Mel频率倒普系数(MFCC)法及矢量量化(VQ)法的语音识别技术对咳嗽声音进行自动识别.方法 在安静环境下,对5例健康成年人和15例咳嗽患者的非咳嗽和咳嗽声音进行录音,分别随机分为训练样本和测试样本.训练样本用于生成咳嗽识别软件的码本,并用该码本对测试样本进行自动识别分析.同时与人工识别的结果进行对比,计算敏感性、特异性,记录两种方法的识别时间.结果 用于码本生成的咳嗽声音和非咳嗽声音均为200次,测试样本的咳嗽和非咳嗽声音分别为375次和125次.人工识别和通过码本自动识别测试样本的时间分别为33 min 18 s和1min 35 s;码本自动识别咳嗽声音的敏感性和特异性分别为98.93%和100%.结论 基于VQ的双门限法及MFCC法可用于咳嗽声音的自动识别.