/n/-/l/音位合并现象的神经机制：来自MMN的证据

采用ERP技术,比较音位合并者与非音位合并者辨别合并音位/n/-/l/的脑电和行为反应。结果发现,非音位合并者在注意前阶段展现了显著的MMN;而音位合并者没有展现MMN,但在晚期展现了一个显著的负波。行为实验发现,相比于音位合并者,非音位合并者在分辨/n/-/l/时正确率更高,反应时更短。这些结果表明：两组被试区分/n/-/l/的能力在早期自动加工阶段就已经有了显著的差异。方言经验可能降低了音位合并者在听觉感觉加工阶段检测合并音位差异的敏感度。     

Differential effects of aging on processes underlying task switching

In this study, we used event-related brain potentials (ERPs) to examine the effects of aging on processes underlying task switching. The response time data revealed an age-related increase in mixing costs before controlling for general slowing and no effect of aging on switching costs. In the cue-locked epoch, the ERP data revealed little effect of age on the parietal P3 related to cue encoding, an age-related decrease in parietal activity related to cue retrieval, and an age-related increase in the amplitude of the parietal and frontal activity related to task set configuration and rule mapping. In the target-locked epoch, there was differential neural recruitment in younger and older adults in response to task mixing. These data are consistent with the idea that older adults may not fully implement task set before onset of the target stimulus.     

Three kinds of rhymes: An ERP study

In a simple prime-target visual rhyming paradigm, pairs of words, nonwords, and single letters elicited similar event-related potential (ERP) rhyming effects in young adults. Within each condition, primes elicited contingent negative variation (CNV) while nonrhyming targets elicited more negative waveforms than rhyming targets within the 320-500ms (N400/N450) time window. The target rhyming effect, apparently primarily an index of phonological processing, was similar across conditions but tended to be smaller in mean amplitude for letters. One of the first reports of such a letter rhyming effect in the ERP literature, these findings could be important developmentally because letter rhyme tasks simultaneously index the two best predictors of ease of learning to read: letter name knowledge and phonological awareness.     

决策中后悔的ERP研究

采用运气轮博弈范式探讨后悔的加工时程。分析决策正误的ERPs发现,200～300ms决策错误比正确诱发更为负走向的波,表现为典型的FRN（feedback-related negativity, FRN）;300～400ms决策正确比错误诱发更大的P300。500～900ms决策正确比错误诱发更大的LPC（late positive component, LPC）,并表现出明显的右半球优势效应。上述结果支持了FRN加工反馈刺激显著性信息和P300加工反馈刺激效价的观点,研究发现后悔与LPC可能具有密切关联。将来研究须在控制得失程度基础上,考察FRN、P300和LPC与效价、得失及得失程度和情绪体验的关系。     

Comparison of chemosensory, auditory and visual event-related potential amplitudes

To enhance understanding of neuropsychological processing underlying chemosensory event-related potentials (CSERPs), the objective of the present study was to compare CSERPs with auditory (AERPs) and visual event-related potentials (VERPs), and to approach the question of similarities in neuropsychological processing by means of correlation and cluster analyses. A multisensory ERP protocol was used, in which olfactory/chemosomatosensory (pyridine), auditory (1000-Hz tone) and visual (white circle) stimuli were presented in a pseudo-randomized sequence to 18 young, healthy adults. The results show (1) a morphological relation between P2 and P3 components that is different for the chemosensory than for the auditory and visual modalities, (2) a relatively weak association between the chemosensory and auditory/visual modalities for P3 in terms of both correlation and cluster, and (3) a P2/P3 cluster for the chemosensory but not auditory or visual modality. This supports the claim that the chemosensory P2 and P3 components reflect similar neuropsychological processes.     

内观疗法对情绪体验影响的ERP研究

采用事件相关电位技术(ERPs)考察内观疗法对情绪体验影响的变化特点,以探明内观疗法是否引起情绪体验的变化。结果表明,内观组在400-1100ms平均波幅显著大于对照组,在内观组和对照组间,出现了显著的组间差异。由此得出结论,说明了内观疗法对情绪体验产生了影响,主要体现在情绪体验的深度与弥散性上。     

心算活动中混合策略选择的ERP研究

考察问题大小、距离、奇偶及答案正误对心算策略选择的影响。采用先答案后算式的呈现方式, 记录了15名被试的64导ERP。研究发现, 在小问题中, 错误答案与正确答案相比, 诱发了算术不一致N400, 距离和奇偶因素影响其波峰及潜伏期。在大问题中, 距离和奇偶因素影响晚期正波, 近距离奇偶一致情境诱发了波幅较小的晚期正慢波。表明在混合情境, 距离比奇偶信息优先得到加工; 在小问题心算中距离和奇偶信息影响答案提取, 而在大问题心算中, 对于依靠距离信息较难直接判断的小距离问题, 在进一步的加工中会借助奇偶信息判断是否采用精确计算策略。     

启动效应的ERP研究综述

近年来,国内外学者以ERP为工具,对启动效应进行了不少研究,并得到一些有意义的结果。例如,在知觉启动方面,发现视觉运动启动的神经机制不同于其它知觉型启动,它既涉及视觉加工的较早阶段,也涉及到较晚阶段。再如,词的重复效应不同于物体的重复效应等等。关于语义型启动的ERP研究,主要围绕N400和N450进行。本文对该领域的一些重要研究进行了介绍和总结,并对该领域中的一些基本研究范式问题进行了讨论。     

听觉呈现条件下汉语双字词语义和语音启动的ERP研究

在词汇决定实验中研究语义启动和语音启动,材料为通过听觉呈现的汉语双字词组成的词对(间隔600ms),记录行为数据和ERP数据,结果发现：(1)启动词与目标词之间的语义联系可显著改善对目标词的加工,表现为错误率降低、反应时缩短,以及N400波幅降低;(2)启动词与目标词之间的语音一致对目标词的加工既有干扰作用,又有促进作用。表现为错误率提高,但反应时趋向缩短,N400波幅亦呈下降趋势;(3)启动词与目标词首音相同比尾音相同有更大的干扰作用。