自动化情绪调节中存在积极效应吗:来自ERPs的证据

采用线索Go/Nogo任务,运用ERPs技术考察了老年人和青年人在自动化情绪调节上的差异。ERPs结果显示:⑴愉快面孔比中性面孔诱发的Go-N2波幅较小,潜伏期较短;Nogo-P3波幅较大,潜伏期较短,表明情绪面孔比中性面孔更能吸引注意;⑵在愉快面孔上,老年组比青年组的Go/Nogo-P3波幅大、潜伏期差异不显著;在悲伤面孔上,老年组比青年组的Go/Nogo-P3波幅大,Nogo-P3潜伏期长,说明老年组比青年组更加抑制对悲伤面孔的反应,老年人在自动化情绪调节中表现出一定程度的积极效应。     

返回抑制过程中情绪面孔加工优先：ERPs研究

返回抑制(IOR)是指注意过程中个体对已搜索过的位置进行抑制, 从而在随后该位置上出现目标时发生注意重新定向或反应变慢的过程。本研究使用ERPs技术, 采用线索-靶子范式, 考察了情绪目标辨别任务中IOR的发生过程及二者的神经机制。结果发现, 与无效线索相比, 有效线索下的P1波幅更小, N1波幅更大, 正性、负性面孔N170的波幅比中性面孔大。表明当要求被试做情绪辨别任务时, IOR与对情绪信息的反应之间发生了分离, 表现出情绪加工的优先。这说明IOR和情绪偏向是发生在两种不同神经通路上的适应机制, 也为进一步探究注意与情绪的关系问题提供了来自神经电生理学的证据。     

预期焦虑对面孔表情加工的影响

预期焦虑是由于对未发生结果的负性投射造成的焦虑情绪。本文比较了被试在不同预期焦虑水平下观看愉快、中性及恐惧面孔时的行为和脑电数据。发现在高预期焦虑水平下,恐惧面孔诱发的N170波幅显著大于低预期焦虑水平,而愉快和中性面孔在两种水平下诱发的波幅差异不显著;且预期焦虑水平对恐惧面孔诱发的N170波幅的调节强度与个体的特质焦虑得分显著相关。这些结果表明,预期焦虑水平会影响面孔表情加工,且不同情绪面孔受到的影响不同。我们推测,预期焦虑水平会通过影响杏仁核等脑区的激活来调节颞上回对恐惧面孔的加工。     

低自尊个体注意偏向的ERP研究

本研究以高兴、愤怒和中性面孔图片为实验材料,采用空间线索任务,借助事件相关电位技术(ERP)探讨低自尊个体注意偏向的内在机制及生理基础,即从电生理的角度,探讨注意偏向的内在机制是反映了注意的快速定向还是注意的解脱困难,亦或是既有快速注意定向又伴随注意的解脱困难。行为数据发现,高低自尊个体在有效提示下的反应显著快于无效提示条件。脑电数据发现,无效提示条件下,愤怒面孔后的靶子比高兴和中性面孔后的靶子在低自尊个体中诱发了更大的P1和更小的N1波幅,有效提示下无显著差异;高自尊个体在N1和P1波幅上无显著结果。晚期P300成分上,无效提示比有效提示诱发了更正的波幅,未发现自尊相关的显著差异。结果表明,低自尊个体对评价性威胁信息(愤怒)的注意偏向是对威胁信息(愤怒)的注意解脱困难。     

负性情绪干扰行为抑制控制:一项事件相关电位研究

以往研究提示,行为抑制控制与视觉情绪加工的神经活动存在交互作用,而视觉材料诱发的正、负情绪如何影响行为控制加工过程尚不清楚。采用双选择情绪oddball范式与事件相关电位(ERP)技术,本研究假设视觉情绪刺激的呈现对个体的行为控制能力具有显著影响。实验要求被试对标准刺激与偏差刺激(85%vs.15%)分别做不同的按键反应。偏差刺激由正、负、中三种来自中国情绪图片系统的情绪图片组成。行为结果发现,负性条件下的反应时间显著长于中性与正性条件,而三类偏差刺激的反应时均显著长于标准刺激的反应时。ERP结果显示,不论效价,在240～300ms与350～550ms两个时间窗口,偏差刺激与标准刺激诱发的平均波幅差异显著,表明本研究条件下行为抑制控制效应显著。在代表行为控制加工的偏差-标准差异波中,在上述两窗口内分别出现显著的N2与P3成分。负性条件下N2及P3潜伏期显著长于中性条件;而负性条件下N2波幅显著大于而P3波幅显著小于中性条件。相反,正性条件下N2波幅显著小于而P3波幅显著大于中性条件。因此,本研究从行为与脑电两个层面揭示了情绪对行为控制过程的影响:负性情绪减弱个体的行为控制能力,从而导致个体对反应冲突的觉察变慢及对优势反应的抑制过程更长。相反,正性情绪对行为控制过程可能具有促进作用。     

两种任务下情绪韵律的加工进程

采用ERP技术分别考察了情绪判断和性别判断任务下情绪韵律的加工进程。结果显示：在175-275ms时间段,情绪韵律的加工受实验任务的调节,情绪判断任务下存在效价主效应及负性偏向,愤怒比高兴和中性诱发了更正的P2成分,而性别判断任务则无效价效应。在后期评价加工及反应准备阶段（400-800ms）,两种任务下,愤怒都比高兴和中性诱发了更正的晚成分。上述结果说明,不同情绪韵律的识别存在不同的认知机制,并在一定程度上会受加工任务的调节。     

场景的不同空间频率信息对面部表情加工的影响:来自ERP的证据

使用事件相关电位(event-related potentials,ERPs)技术考察场景(scene)的不同空间频率信息对面部表情加工的影响。结果发现:对于完整频谱的正常场景来说,中性场景中的恐惧面孔所诱发的N170波幅显著大于消极场景中的恐惧面孔,但该场景效应并未出现在高、低空间频率场景中;另外,中性场景中的中性面孔所诱发的N170波幅显著大于消极场景中的中性面孔,该效应发生于三类不同空间频率的场景中。该研究结果表明,场景对恐惧面孔早期知觉编码加工的影响依赖于场景完整频谱信息。相对于恐惧面孔,中性情绪面孔的结构化编码加工更容易受到消极情绪场景的干扰,而且这种干扰能够发生在场景仅有粗略轮廓信息以及细节线条信息的情况下。     

面孔加工的结构编码阶段异族效应的加工方式： ERPs研究

实验采用事件相关电位（ERPs）技术,以大学生为被试,运用非洲、欧洲、亚洲三个不同种族的面孔照片,探究异族效应与加工方式的关系。行为实验结果显示,被试对非洲面孔的反应时快于欧洲面孔,且两者均快于亚洲面孔。ERP研究结果显示,亚洲面孔的N170波幅显著小于非洲和欧洲面孔的波幅,后两者的N170波幅没有差异,而且亚洲面孔的倒置效应最大。研究结果说明相对于异族面孔,本族面孔更多地使用构型编码的加工方式,且N170成分表现出右半球优势。     

负性情境诱导下抑郁个体的情绪Stroop效应：ERPs研究

运用ERPs技术探讨了正常和抑郁个体在中性和负性情境诱导下的情绪Stroop效应。结果发现正常被试在负性情境下对中性词判断的错误率比在中性情境下更高,对负性词加工的P1波幅减小、N1增大,出现了Stroop效应;抑郁被试在两种情境下对负性词加工的P1和 N1波幅没有差异。研究结果提示,抑郁个体在负性情境下出现注意脱离困难和资源不足,难以解决情绪冲突任务,支持了注意脱离损伤假说,并进一步说明抑郁个体的情绪选择性注意加工会受到心境一致性状态的影响,因过多的注意资源卷入从而出现负性情绪调节不良。实验结果为探讨抑郁个体对负性情绪的注意加工和调节过程提供了来自电生理的证据。     

阈下抑郁个体对负性情绪刺激的注意解脱困难

本研究拟采用点探测范式及不同情绪内容的面孔刺激（高兴、中性、悲伤和愤怒）考察阈下抑郁个体的负性注意偏向及其内在机制。点探测任务中情绪面孔配对呈现（负性-中性、正性-中性）,配对面孔中的情绪线索位置与靶刺激的位置构成负性一致/不一致和正性一致/不一致条件,同时实验中加入“中性-中性”面孔线索作为一致和不一致条件的对比基线来考察注意偏向的内在机制。结果发现,阈下抑郁个体在负性不一致条件下的反应时显著长于负性一致条件,表明阈下抑郁个体具有对负性刺激的注意偏向;进一步比较发现,阈下抑郁个体在负性不一致条件下的反应时显著的长于“中性-中性”基线条件,而负性一致条件与基线之间差异不显著,表明阈下抑郁个体的负性注意偏向为对负性刺激的注意解脱困难。结果另发现,阈下抑郁个体未能像无抑郁对照组个体表现出对正性刺激的注意偏向。结果表明,处于阈下抑郁状态的个体表现出对负性刺激的注意偏向,具体为对负性刺激的注意解脱困难,其原因可能是由于阈下抑郁个体在注意控制和情绪调节功能上的紊乱。     

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？     

注视方向和面部表情对注意朝向的影响

摘 要 本文以三种表情面孔为材料,运用事件相关电位（ERP）方法探讨表情线索在注意朝向中与注视转移发生的交互及两者如何共同影响观察者的反应。结果发现：（1）线索效应在三种表情面孔的两种SOA中都出现了;（2）SOA较长时,注视线索效应量间的显著差异出现在中性和恐惧面孔、高兴和恐惧面孔间;（3）面部表情的效应出现在了表情线索诱发的P1成分上;（4）目标诱发的P1和N1说明了注视线索效应的存在及与表情间的交互。结论：表情线索先对观察者的朝向反应产生影响,随后是注视线索及其与表情线索发生的交互。     

Fearful expressions enhance recognition memory: electrophysiological evidence

Facial expressions play a key role in affective and social behavior. However, the temporal dynamics of the brain responses to emotional faces remain still unclear, in particular an open question is at what stage of face processing expressions might influence encoding and recognition memory. To try and answer this question we recorded the event-related potentials (ERPs) elicited in an old/new recognition task. A novel aspect of the present design was that whereas faces were presented during the study phase with either a happy, fearful or neutral expression, they were always neutral during the memory retrieval task. The ERP results showed three main findings: An enhanced early fronto-central positivity for faces encoded as fearful, both during the study and the retrieval phase. During encoding subsequent memory (Dm effect) was influenced by emotion. At retrieval the early components P100 and N170 were modulated by the emotional expression of the face at the encoding phase. Finally, the later ERP components related to recognition memory were modulated by the previously encoded facial expressions. Overall, these results suggest that face recognition is modulated by top-down influences from brain areas associated with emotional memory, enhancing encoding and retrieval in particular for fearful emotional expressions.     

Attentional shifts to emotionally charged cues: Behavioural and erp data

Abstract

When information activated in memory involves emotional associations, the ability to shift attention away from an emotional cue is impaired compared to an emotionally neutral cue. The purpose of the present study was to investigate how emotional stimuli modulate attentional processes, and how this is reflected in localised brain electrical activity. Eight emotion and eight neutral words served as cues in a covert attention spatial orienting task. The cues were either valid or invalid indicators of which hemifield the target would be presented to. In the remaining trials, no cue was presented prior to the target. Twenty subjects were instructed to manually respond to the target as fast as possible. Event-related potentials (ERPs) showed an enhanced P3 component to the emotion words. The ERPs to the target showed enhanced P1 and P3 components on invalid trials, with emotional cues. There were faster reaction times (RTs) to validly cued targets, but only when the emotion words served as cues. The results demonstrated that the emotional cues elicited sustained focused attention, facilitating an engage mechanism of spatial orienting.     

Conscious and unconscious face recognition is improved by high-frequency rTMS on pre-motor cortex

Simulation process and mirroring mechanism appear to be necessary to the recognition of emotional facial expressions. Prefrontal areas were found to support this simulation mechanism. The present research analyzed the role of premotor area in processing emotional faces with different valence (positive vs. negative faces), considering both conscious and unconscious pathways. High-frequency rTMS (10 Hz) stimulation was applied to prefrontal area to induce an activation response when overt (conscious) and covert (unconscious) processing was implicated. Twenty-two subjects were asked to detect emotion/no emotion (anger, fear, happiness, neutral). Error rates (ERs) and response times (RTs) were considered in response to the experimental conditions. ERs and RTs decreased in case of premotor brain activation, specifically in response to fear, for both conscious and unconscious condition. The present results highlight the role of the premotor system for facial expression processing, supporting the existence of two analogous mechanisms for conscious and unconscious condition.     

阈下情绪面孔的注视线索提示效应

采用线索-靶子范式，利用2个预实验和1个正式实验，考察阈下不同情绪面孔的注视线索提示效应。要求被试在具有表情与注视线索的面孔呈现完毕后，快速而准确地对目标的位置进行判断。记录被试反应时间。结果显示，当被试未有意识的觉察到注视线索与面孔表情时，注视线索提示效应存在，并受到表情的调节。表现为：在注视线索有效并伴有恐惧表情时，被试对于目标的判断更加迅速；当比较不同表情下线索无效与线索有效条件下的反应时差异时发现，恐惧表情面孔出现时，线索无效与线索有效条件之间反应时的差异最大。结果表明，阈下情绪刺激能够激发个体更原始的生物性反应；在早期注意阶段，个体对于恐惧信息更加敏感，注意存在负向情绪偏差。     

On the automaticity of emotion processing in words and faces: event-related brain potentials evidence from a superficial task

The degree to which emotional aspects of stimuli are processed automatically is controversial. Here, we assessed the automatic elicitation of emotion-related brain potentials (ERPs) to positive, negative, and neutral words and facial expressions in an easy and superficial face-word discrimination task, for which the emotional valence was irrelevant. Both emotional words and facial expressions impacted ERPs already between 50 and 100 ms after stimulus onset, possibly reflecting rapid relevance detection. Following this initial processing stage only emotionality in faces but not in words was associated with an early posterior negativity (EPN). Therefore, when emotion is irrelevant in a task which requires superficial stimulus analysis, automatically enhanced sensory encoding of emotional content appears to occur only for evolutionary prepared emotional stimuli, as reflected in larger EPN amplitudes to faces, but not to symbolic word stimuli.     

Event-related potentials to schematic faces in social phobia

Social phobia has been associated with an attentional bias for angry faces. This study aimed at further characterising this attentional bias by investigating reaction times, heart rates, and ERPs while social phobics, spider phobics, and controls identified either the colour or the emotional quality of angry, happy, or neutral schematic faces. The emotional expression of angry faces did not interfere with the processing of their colour in social phobics, and heart rate, N170 amplitude and parietal late positive potentials (LPPs) of these subjects were also no different from those of non-phobic subjects. However, social phobics showed generally larger P1 amplitudes than non-phobic controls with spider phobic subjects in between. No general threat advantage for angry faces was found. All groups identified neutral schematic faces faster and showed larger late positive amplitudes to neutral than to emotional faces. Furthermore, in all groups the N170 was modulated by the emotional quality of faces. This effect was most pronounced in the emotion identification task.     

不同注意条件下动态面孔表情识别的ERP研究

利用ERP技术对16名被试在不同注意负荷下对动态表情识别的脑时程特点进行了考察,结果发现：N170成分不受注意负荷和表情效价影响;低注意负荷条件下动态表情加工早期负性表情诱发的EPN成分（early posterior negativity）显著大于中性、正性表情,后期高级分析阶段正、负性表情均诱发明显的LPP成分（late positive potentials）,且负性较正性表情诱发更大的LPP成分;而在高注意负荷条件下并未发现表情识别诱发明显的EPN或LPP成分。这些结果说明,动态表情识别明显受到注意资源调节,只有在注意资源不断增加时表情加工才会出现注意偏向效应,尤以负性表情的加工优势最为凸显且持久,正性表情相对微弱和短暂。