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1.
The differences in P300 latency, P300 amplitude, response selection, and reaction time between skilled and less-skilled cricket batsmen have been investigated. Eight skilled and ten less-skilled right-handed batsmen each viewed 100 in-swing, 100 out-swing, and 40 slower deliveries displayed in random sequence from projected video footage whilst their responses and electroencephalograms were recorded. Logistic regression was used to derive a discriminative function for the P300 data. This was done to determine whether the skilled batsmen differed from the less-skilled batsmen on the basis of pooled P300 amplitude and latency data. All the batsmen were correctly characterised as being skilled or less-skilled. Logistic regression equations with reaction time and correctness of response data indicated that behavioural data do not correctly classify skilled performance. It is suggested that skilled cricket batsmen have a superior perceptual decision-making ability compared with less-skilled cricket batsmen, as measured by P300 latency and amplitude. This appears to be the first study showing a link between skill and cerebral cortical activity during a perceptual cricket batting task and it could pave the way for future studies on mental processing in cricket batsmen.  相似文献   

2.
In an attempt to elucidate the nature of the subject’s strategy in a two-interval forcedchoice auditory detection task, event-related potentials were studied at two intensities which yielded mean accuracies of 82% and 98%. Subjects reported the observation interval in which they judged the signal to be present and the confidence of the judgment. Principal components varimax analyses yielded four components: a CZ maximal P300, a Slow Wave, a slow negative shift, and a late negative component. The P300 amplitude findings suggest that different strategies are utilized for high-confidence and low-confidence detections. At high confidence, P300 amplitude is large for the observation interval in which the signal is presented, indicating a strategy involving serial independent detection. However, the P300 latency findings at high confidence suggest that absence of the signal in the first observation interval is nonetheless noted: P300 latency in response to signal presence is shorter for the second observation interval than for the first observation interval. At low confidence, P300 is small or absent for both observation intervals, indicating a deferred decision, presumably arrived at through comparison of the two percepts.  相似文献   

3.
Event-related potentials were recorded from young adults during a visual search task in order to evaluate parallel and serial models of visual processing in the context of Treisman's feature integration theory. Parallel and serial search strategies were produced by the use of feature-present and feature-absent targets, respectively. In the feature-absent condition, the slopes of the functions relating reaction time and latency of the P3 component to set size were essentially identical, indicating that the longer reaction times observed for larger set sizes can be accounted for solely by changes in stimulus identification and classification time, rather than changes in post-perceptual processing stages. In addition, the amplitude of the P3 wave on target-present trials in this condition increased with set size and was greater when the preceding trial contained a target, whereas P3 activity was minimal on target-absent trials. These effects are consistent with the serial self-terminating search model and appear to contradict parallel processing accounts of attention-demanding visual search performance, at least for a subset of search paradigms. Differences in ERP scalp distributions further suggested that different physiological processes are utilized for the detection of feature presence and absence.  相似文献   

4.
The authors examined the processing of phonological and orthographic word representations among 17 dyslexic and 16 normal college-level readers using Event-Related Potential measures. They focused on 2 early components--the P200 and the P300. The results revealed P200 and P300 components of lower amplitude and later latency among dyslexic readers than among normal readers for both types of word representation. Group differences were greatest for phonological representations. In addition, the authors observed greater time gaps among dyslexic readers than among normal readers between different processing stages (i.e., between P2 and P3 peaks, between P3 and reaction time). Combined, the data suggest a consistent speed-of-processing deficit among dyslexic readers that is evident within and between stages of cognitive processing. The results are discussed in the context of deficits in stimulus encoding and working memory. In addition, the authors discuss the need for accurate timing and synchronization of phonological and orthographic codes for efficient word recognition.  相似文献   

5.
In a simple auditory rhyming paradigm requiring a button–press response (rhyme/nonrhyme) to the second word (target) of each spoken stimulus pair, both the early (P50, N120, P200, N240) and late (CNV, N400, P300) components of the ERP waveform evidenced considerable change from middle childhood to adulthood. In addition, behavioral accuracy and reaction time improved with increasing age. In contrast, the size, distribution and latency of each of several rhyming effects (including the posterior N400 rhyming effect, a left hemisphere anterior rhyming effect, and early rhyming effects on P50 latency, N120 latency and P200 amplitude) remained constant from age 7 to adulthood. These results indicate that the neurocognitive networks involved in processing auditory rhyme information, as indexed by the present task, are well established and have an adult–like organization at least by the age of 7.  相似文献   

6.
P300 and probability in children   总被引:1,自引:0,他引:1  
The P300 event-related brain potential (ERP) was elicited in three groups of 12 children each, ages 5-9, 10-14, and 15-19 years. A simple auditory task was employed in which subjects indicated with a finger movement when a randomly occurring target tone (high pitch) was presented in a series of standard (low pitch) tones. The probability of the target tone was varied across conditions at 0.10, 0.30, or 0.50 to determine if P300 amplitude would respond similarly across age groups. Immediate memory capacity was measured with forward and reverse digit spans. P300 amplitude increased with decreases in target stimulus probability for each age group and also tended to become larger with age. P300 latency decreased in the same fashion across probability levels as age increased. Digit span demonstrated the usual increase with age. The results suggest that cognitive development is indexed by decreases in P300 latency, and that P300 amplitude changes from the probability of the target stimulus are similar across age groups. The implications for the theoretical interpretation of the P300 and application of ERPs for evaluating cognitive development are discussed.  相似文献   

7.
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。  相似文献   

8.
心理性应激的时间加工进程:来自ERP的证据*   总被引:1,自引:0,他引:1  
采用有时间压力的算术题目诱发被试的心理性应激体验,并用事件相关电位技术(ERP)探讨心理性应激发生时大脑神经活动的时程变化。行为数据结果发现有时间压力下被试的反应时更短;脑电数据结果发现有时间压力组的容易题目比无时间压力组的容易题目诱发出更大的N1峰值、更长的P2潜伏期和更大的P300波幅;有时间压力组的困难题目比无时间压力组的困难题目同样诱发出更大的N1峰值、更长的P2潜伏期和更大的P300波幅,但这种组别主效应仅表现在部分电极点上。该研究结果表明心理性应激增加了早期知觉加工的负载,导致知觉加工速度减慢,在信息加工后期阶段需要占用更多的认知资源。  相似文献   

9.
Event related potentials (ERP) and reaction times (RT) were recorded during the performance of memory-retrieval tasks using the Japanese kanji characters. P300 latency and RT increased as the memory set-size increased. The slope differences between RT and P300 latency were larger for stimuli when concrete kanji were used than when abstract kanji were used. This suggests that, in memory search, the 20 subjects were likely to employ direct lexical access when processing concrete kanji and likely to use phonetic coding when processing abstract kanji.  相似文献   

10.
采用事件相关电位(ERPs)技术考察了奖赏预期对人类面孔情绪识别的影响。实验采用线索-目标范式, 分别记录了被试在奖赏预期条件下以及无奖赏预期条件下对正性、中性和负性面孔进行情绪辨别任务的ERP数据。行为结果显示, 被试在奖赏预期条件下的反应时快于无奖赏预期条件下的反应时, 对情绪面孔的反应时快于对中性面孔的反应时。ERPs数据显示, 奖赏线索比无奖赏线索诱发了更正的P1、P2和P300成分。目标刺激诱发的P1、N170波幅以及N300均受到奖赏预期的调节, 在奖赏预期条件下目标诱发了更正的ERPs。P1、N170、VPP等成分没有受到面孔情绪的影响, 而额中央位置的N300波幅显示情绪(正性与负性)面孔与中性面孔加工的差异。重要的是, N300波幅出现奖赏预期与情绪的交互作用, 正、负情绪加工效应以及负性偏向效应受奖赏预期的差异性影响。正性情绪加工效应不受奖赏预期的影响, 而负性情绪加工效应和负性偏向效应在奖赏预期条件下显著大于无奖赏预期条件下。这些结果说明, 奖赏预期能够调节对面孔情绪的加工, 且不同加工进程中奖赏对情绪加工的调节作用不同。动机性信息调节注意资源的分配, 促进了个体在加工面孔情绪时的负性偏向。  相似文献   

11.
The study evaluated the off-line relationship of attention, memory and other cognitive performances with the auditory event-related potentials P3 (P300) and N2. The sample comprised 200 middle-aged construction workers. Verbal, visuomotor and memory tests were administered. Attentional domains were examined using CogniSpeed software. Slowed reaction times in the test of sustained attention (vigilance) were associated with delayed P3 latency (p < 0.001) and decreased P3 amplitude (p = 0.005), as well as with delayed N2 latency (p < 0.001). Visuomotor slowing in Digit Symbol was also related to delayed P3 latency (p = 0.030) and decreased P3 amplitude (p = 0.014). In contrast, mild cognitive impairment, short- and long-term memory, and concentrating or sharing attention with high working memory demands were not related to P3. The results suggest that P3 is linked to attentional performance with low working memory demands rather than to effortful working memory updating, retrieval from memory stores, or mild cognitive impairment.  相似文献   

12.

Background

Decreased speed of information processing is a hallmark of Alzheimer’s disease (AD) and mild cognitive impairment (MCI). Recent studies suggest that response speed (RS) measures are very sensitive indicators of changes in longitudinal follow-up studies. Insight into the psycho-physiological underpinnings of slowed RS can be provided by measuring the associated event-related potentials (ERP).

Aims

The current study aims to investigate the relation between RS and its psycho-physiological correlates in AD and MCI.

Methods

Fifteen psychoactive drug-naïve AD patients, 20 MCI patients and twenty age-matched, healthy control subjects participated. Response speed was measured during a simple (SRT) and choice reaction time task (CRT). An oddball and contingent negative variation (CNV) paradigm were used to elicit ERP. To evaluate test-retest reliability (TRR), subjects underwent a similar assessment one week after the first.

Results

The SRT and CRT distinguished the patient groups significantly. The P300 amplitude and latency also distinguished the groups and showed a significant correlation with response speed. The CNV amplitude did not reveal a significant difference between groups and also showed a low TRR.The TRR of the SRT, CRT and P300 amplitude and latency in general was moderate to high.The current study suggests that response speed measures on a behavioural and psycho-physiological level deserve attention as a possible marker in the diagnosis and follow-up of AD.  相似文献   

13.
Dissociative effects of alcohol on recollective experience   总被引:3,自引:0,他引:3  
This article reports a study comparing the effects of a single dose of alcohol with a matched placebo drink on recognition memory with and without conscious recollection. A double-blind, cross-over design was used with healthy volunteers who were all social drinkers. Processing depth at study was manipulated using generate versus read instructions. Conscious recollection at test was assessed using the remember-know-guess paradigm (Gardiner, 1988; Tulving, 1985). Alcohol significantly reduced conscious recollection (remember responses) but had no effect on recognition in the absence of conscious recollection (know responses). False alarms rates were low and unaffected by alcohol. Previous findings that generation effects are found only for remember responses were closely replicated. A further dissociation of the generation effect occurred between treatments in that deeper processing at study facilitated recognition on placebo but not on alcohol. That both alcohol and depth of processing produce dissociative effects on recollective experience provides further evidence that remembering and knowing reflect distinct memory systems.  相似文献   

14.
Fournier, L. R., Eriksen, C. W. and Bowd, C. (1998. Multiple feature discrimination faster than single feature discrimination within the same object? Perception & Psychophysics 60, 1384-1405) found that judging the presence of multiple features within an object is faster than judging the presence of the least discriminable of these features alone (multiple feature benefits, MFBs). When an 'absent' response is required, responses are slower when some of the relevant (target) features are present (multiple feature costs, MFCs). The present study utilized psychophysiological measures (of the event-related brain potential and the electromyogram) to determine the contributions of response priming and stimulus evaluation processes (P300 latency) to these effects. P300 latency and reaction time (RT) both showed evidence of MFBs and MFCs. These findings suggest that MFBs and MFCs can be attributed to processing that occurs prior to response selection. No dissociations between P300 latency and RT measures were found for 'present' responses across the single and multiple feature judgements. However, for 'absent' responses, partial dissociations were found between these measures, and partial errors and longer response execution intervals were observed more often when an object contained some target features. These findings suggest that response priming contributes to MFCs, but may not contribute to MFBs.  相似文献   

15.
When a sound occurs at a predictable time, it gets processed more efficiently. Predictability of the temporal structure of acoustic inflow has been found to influence the P3b of event‐related potentials in young adults, such that highly predictable compared to less predictable input leads to earlier P3b peak latencies. In our study, we wanted to investigate the influence of predictability on target processing indexed by the P3b in children (10–12 years old) and young adults. To do that, we used an oddball paradigm with two conditions of predictability (high and low). In the High‐predictability condition, a high‐pitched target tone occurred most of the time in the fifth position of a five‐tone pattern (after four low‐pitched non‐target sounds), whereas in the Low‐predictability condition, no such rule was implemented. The target tone occurred randomly following 2, 3, 4, 5, or 6 non‐target tones. In both age groups, reaction time to predictable targets was faster than to non‐predictable targets. Remarkably, this effect was largest in children. Consistent with the behavioral responses, the onset latency of the P3b response elicited by targets in both groups was earlier in the predictable than the unpredictable conditions. However, only the children had significantly earlier peak latency responses for predictable targets. Our results demonstrate that target stimulus predictability increases processing speed in children and adults even when predictability was only implicitly derived by the stimulus statistics. Children did have larger effects of predictability, seeming to benefit more from predictability for target detection.  相似文献   

16.
从发展心理学的角度.对幼儿到大学六个年龄组的儿童青少年进行了事件相关电位P_(300)测定.结果发现:反映大脑认知功能的事件相关电位P_(300)各成分随着年龄增长而发展的趋势十分明显,从而进一步说明了认知发展的特点与大脑高级神经系统活动功能发展特点的密切关系。  相似文献   

17.
The aim of this study was to examine the effects of frequency of occurrence of stop signals in the stop-signal paradigm. Presenting stop signals less frequently resulted in faster reaction times to the go stimulus and a lower probability of inhibition. Also, go stimuli elicited larger and somewhat earlier P3 responses when stop signals occurred less frequently. Since the amplitude effect was more pronounced on trials when go signals were followed by fast than slow reactions, it probably reflected a stronger set to produce fast responses. N2 and P3 components to stop signals were observed to be larger and of longer latency when stop signals occurred less frequently. The amplitude enhancement of these N2 and P3 components were more pronounced for unsuccessful than for successful stop-signal trials. Moreover, the successfully inhibited stop trials elicited a frontocentral P3 whereas unsuccessfully inhibited stop trials elicited a more posterior P3 that resembled the classical P3b. P3 amplitude in the unsuccessfully inhibited condition also differed between waveforms synchronized with the stop signal and waveforms synchronized with response onset whereas N2 amplitude did not. Taken together these findings suggest that N2 reflected a greater significance of failed inhibitions after low probability stop signals while P3 reflected continued processing of the erroneous response after response execution.  相似文献   

18.
The relation between intelligence and speed of auditory discrimination was investigated during an auditory oddball task with backward masking. In target discrimination conditions that varied in the interval between the target and the masking stimuli and in the tonal frequency of the target and masking stimuli, higher ability participants (HA) displayed more accurate discriminations, faster response time, larger P300 amplitude, and shorter P300 and mismatch negativity (MMN) latency than lower ability participants (LA). Task difficulty effects demonstrated with variation in mask type indicate that the mask does not interfere with the detection of the deviant target stimulus, but rather that the target and mask are integrated as a single compound stimulus. The temporal effects suggest that the speed of accessing short-term memory is faster for HA than LA and, on the basis of the MMN latency, the effect is accomplished automatically, without focused attention. Moreover, the pattern of results obtained with these data support the view that the accuracy effects are determined by processing speed rather than discrimination ability. Comparator models that accommodate these effects are discussed.  相似文献   

19.
通过ERP方法,考察卡通面孔分类(人和动物)的脑机制及其与卡通面孔识别(人与车)的差异。结果表明,分类任务中,动物面孔VPP潜伏期显著长于人,N170潜伏期主效应不显著、波幅半球效应显著,LPP波幅在顶叶和中央区最大;分类任务VPP和LPP波幅均显著大于识别。结论:卡通面孔分类比识别速度慢、强度大,消耗心理资源多。顶叶和中央区可能是执行分类任务的主要脑区,且加工人类面孔具有优势。面孔加工中结构编码和特征编码可能部分是并行的。  相似文献   

20.
语义距离半球效应的ERP研究   总被引:1,自引:0,他引:1  
以通过视觉通路呈现的汉语双字词为实验材料,操纵启动词与目标词的语义距离。在词汇决定实验中记录ERP,发现:(1)除N300外,P240亦对语义距离敏感,它可能是一种与语义加工有关的新的ERP成分;(2)P240在头皮中央偏左的部位较早出现,但在头皮右侧波幅较大;(3)N300和P240都不存在语义距离的半球效应,该结果没有证实右脑更专擅远距离语义加工的假设,表明使用汉语与使用拼音文字的脑机制存在差异。  相似文献   

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