Left hemisphere selectivity for processing duration in normal subjects

The role of the left cerebral hemisphere for the discrimination of duration was examined in a group of normal subjects. Two tasks were presented: the first required a reaction-time response to the offset of monaural pulse sequences varying in interpulse duration, and the second required the discrimination of small differences in durations, within a delayed-comparison paradigm. In each task a right-ear advantage was obtained when the durations were 50 msec or less. No ear advantage was obtained for the larger durations of 67 to 120 msec. Since the perceptual distinctiveness of phonemes may be provided by durations approximating 50 msec, the nature of the relationship between the left hemisphere's role in temporal processing and speech processing may be elaborated.     

Neurophysiological codes of words in subcortical structures of the human brain.

Investigations into the cerebral mechanisms of mental activity, using modern mathematical-technical capabilities, allows the transition from study of structural-functional organization to a new stage: the study of neural coding of these cerebral processes.Here we present the results of studying the elementary components of the neurophysiological pattern-code of words and the neurophysiological correlates of the simplest mental processes, generalization, and mental conclusion. The elementary components of the pattern-code are the group sequences of neuronal firing with comparatively stable intervals in between. The processes of mental conclusion and decision making occur when full, compressed, and complex patterns-codes appear in the brain.In discussing the data obtained, the problems of relationship between a part and the whole in activity of cerebral systems is considered, and the hypothesis of a dynamic pace-maker mechanism for cerebral organization of mental activity, is proposed.     

Skinner's verbal behavior, Chomsky's review, and mentalism.

Skinner's Verbal Behavior (1957) is a comprehensive treatise that deals with most aspects of verbal behavior. However, its treatment of the learning of grammatical behavior has been challenged repeatedly (e.g., Chomsky, 1959). The present paper will attempt to show that the learning of grammar and syntax can be dealt with adequately within a behavior-analytic framework. There is no need to adopt mentalist (or cognitivist) positions or to add mentalist elements to behaviorist theories.     

面部表情加工的ERP成分

面部表情加工的ERP成分主要包括P1 (80~120 ms)、N170 (120~200 ms), 早期后部负电位(Early Posterior Negativity, EPN, 200~300 ms)和晚期正成分(Late Positive Potential, LPP, 300 ms以后)。这些成分代表了表情加工的不同阶段, 具有不同的心理含义。P1成分只对威胁类表情(恐惧, 厌恶和愤怒)敏感, 反映了对威胁面孔的快速探测, 具有自动加工的性质。N170成分与表情结构信息的编码有关, 同样具有自动加工的性质。EPN反映了对情绪信息的选择性注意, 具有情绪普遍性, 情绪场景图片和表情刺激都会对它产生影响, 在特定的条件下具有自动加工的性质。LPP则反映了对情绪信息的高级认知加工, 较易受注意控制的影响。在对上述成分的特性了解的基础上, 将来的研究应该探索以下问题：(1) P1是否受表情威胁程度的影响？(2) N170受到哪些自上而下因素的影响？(3)那些不能影响N170成分, 却能影响EPN成分的表情刺激是否被当成了普通的情绪刺激来看待？(4)表情加工引发的LPP是否能具有自动加工的性质？(5)不同的基本表情类型(如恐惧和厌恶)是否具有特异性的ERP成分？     

心理性应激的时间加工进程:来自ERP的证据*

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。     

正性情绪诱导下的自我参照加工：来自ERPs的证据

采用事件相关电位考察正性情绪对自我参照加工程度效应的影响。实验采用图片启动范式, 先呈现情绪图片, 然后再呈现自我参照刺激。实验发现, 在P2上, 中性情绪条件比正性情绪条件激发了更大的波幅, 高自我相关的刺激比其它刺激诱发了更短的P2潜伏期; 在N2上, 高自我相关名字比中等自我相关名字和非自我相关名字诱发了更小的N2的波幅和更长潜伏期; 在P3上, 高自我相关名字比中等自我相关名字和非自我相关名字诱发了更大的P3波幅, 中等自我相关名字比非自我相关名字诱发了更大的P3波幅。实验结果表明, 人类大脑对正性情绪刺激的加工可能是不敏感的。无论在正性情绪启动还是中性启动的影响下, 自我参照加工都能展现出稳定的特征, 而且高自我相关的刺激会得到更为深入和精细的加工, 表现出自我参照加工的程度效应。     

社会等级加工的神经基础

社会等级是社会组织的基本原则。社会地位高低的再认与面孔再认及视觉注意均表现出N200的激活, 并不同程度地共享了情感、奖赏回报、数字等级及共情特质等加工的脑区网络, 涉及额区、杏仁核、纹状体、顶内沟和前扣带回皮质等。社会等级加工与5-羟色胺递质多态性等神经递质及内分泌系统具有复杂的交互作用。未来应立足于综合研究和系统分析的视角探讨社会等级加工与神经生物学基础的作用机制并致力于服务人类生活。     

睡眠学习的ERP研究

夜间用脑电监测被试睡眠状态,并反复播放英语单词和中文对译词,第二天用词汇决定任务检查学习效果,并记录ERP,结果发现：（1）与未学过的英—中词对相比,被试对学过的词对中中文词的反应时明显缩短;（2）学过的词对中中文词引发的N600的波幅比未学过的明显降低。以上结果表明睡眠学习效果在内隐记忆测验中明显。另外发现被试几乎不能在播放学过的英语词时说出中文对译词,与未学过的词对相比没有显著差别,提示睡眠学习效果在外显记忆测验中不明显。以上结果表明,在本实验条件下,间接测验比直接测验更敏感。     

Body posture and gender impact neural processing of power-related words

Judging others’ power facilitates successful social interaction. Both gender and body posture have been shown to influence judgments of another’s power. However, little is known about how these two cues interact when they conflict or how they influence early processing. The present study investigated this question during very early processing of power-related words using event-related potentials (ERPs). Participants viewed images of women and men in dominant and submissive postures that were quickly followed by dominant or submissive words. Gender and posture both modulated neural responses in the N2 latency range to dominant words, but for submissive words they had little impact. Thus, in the context of dual-processing theories of person perception, information extracted from both behavior (i.e., posture) and from category membership (i.e., gender) are recruited side-by-side to impact word processing.     

汉字识别中字形畸变和语境的ERP效应

以事件相关电位（ERP）技术和语义启动范式,采用同一字判断（靶字延迟反应）作业,考察字形畸变和语境对低频汉字识别的影响。结果发现,无语义启动时,畸变靶字正确率低于清晰靶字;启动效应只体现在畸变时的正确率上。150–300ms窗口,畸变字比清晰字诱发峰值更负的N170;300–500ms时间窗口,不启动条件诱发平均波幅更负的N400,畸变字诱发更大N400。结论是,畸变字诱发的N170成分,在一定程度上反映了字形加工;N400的语义启动效应和畸变效应,扩展Holcomb的研究,并支持语义提取理论。