结果评价中自我体验与替代体验的参照点效应:一项赌博游戏的ERPs研究

本研究采用"投注—反馈"的虚拟赌博游戏范式,通过2个实验分别检测个体在评价自己决策结果 (实验1)和观察他人决策结果 (实验2)过程中赌注大小(即参照点)对大脑活动的影响。结果发现:(1)体验自我决策结果时,输钱比赢钱诱发更负的FRN,仅有一个负反馈(-10元)表现出以赌注为界的分离,且相对效价一样的反馈值诱发的FRN差异不显著;(2)体验他人决策结果时,无论输赢,有赌注比无赌注诱发的FRN更负;而且相对效价相同的反馈值诱发的FRN差异不显著。据此可以认为,FRN一定程度上反映了以赌注为基准的主观标准对社会信息的评价判断:自我体验中的个体对损失的敏感度远高于收益;而替代体验中的个体更倾向于将"损失更多"看作一种负性结果。     

机会公平影响结果评价的时间特征

以往的研究主要集中于研究结果公平对结果评价的影响,尚未指明机会公平对结果评价的影响。本研究采用事件相关电位技术(ERPs)探讨了机会公平影响结果评价的时间加工特征。结果发现,不利机会不公平会诱发较大的反馈相关负波(FRN)波幅;赢的时候,不利机会不公平和有利机会不公平均会诱发较大的P300波幅,输的时候三种机会公平性诱发的P300波幅不存在显著差异。这说明,FRN和P300是机会公平性的神经指标,机会公平会调节人们对结果的评价。     

社会价值取向对自我社会奖赏加工的影响——来自ERPs的证据

社会价值取向(Social Value Orientation, SVO)是相互依存情境下人们对自己和他人分配结果的一种稳定的社会偏好, 按SVO不同可以将个体分为“亲社会取向”和“亲自我取向”个体。已有研究表明SVO影响个体对涉及自我金钱奖赏的结果评价加工, 而它如何影响自我社会奖赏加工过程尚不明确。本研究让亲社会取向和亲自我取向被试完成涉及自我社会奖赏(包含社会接纳和自我成就感)的猜牌建议给予任务, 同时记录其加工他人对建议的反馈(接受vs.拒绝)和他人最终结果(收益vs.损失)时诱发的脑电成分。结果发现, 在建议反馈加工阶段, 相比亲自我取向个体, 亲社会取向个体在反馈相关负波(FRN)波幅(峰-峰值)和P3平均波幅上, 建议被对方接受和被对方拒绝所诱发的波幅差异均显著; 在他人最终结果加工阶段, 建议被对方拒绝后, 对于亲社会取向个体, 对方损失诱发的反馈相关负FRN波幅比对方收益诱发的波幅更负, 而对方损失诱发的P3波幅小于对方收益诱发的波幅; 对于亲自我取向个体, 对方损失与收益诱发的FRN波幅无差异, 对方损失诱发的P3波幅显著大于对方收益诱发的波幅。这些结果表明社会价值取向调节个体对自我社会奖赏的加工。     

作为效应的ERP研究

晚正成分能够反映不同效价和不同唤醒度的情绪。作为后悔的一种现象,作为效应是否与晚正成分具有关联是研究关心的问题。采用运气轮博弈的范式,记录与分析被试在“做”与“不做”决策下的ERPs。研究发现,决策结果的正误显著影响了FRN、P300和LPC的波幅大小。作为类别对FRN、P300和LPC波幅的影响受到不同决策结果的影响,在决策正确的条件下,作为类别对FRN、P300和LPC波幅不产生影响,而在决策错误的条件下,作为类别对FRN、P300和LPC波幅产生了显著的影响。结果表明作为效应不仅影响了FRN、P300的波幅,同时也影响了LPC的波幅,将来研究应进一步探明晚正成分与后悔的密切关联。     

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。     

测谎中反馈加工的认知神经机制：一项ERP研究

在一个模拟“杀人——侦探”游戏情境中,被试先完成模拟杀人任务,在随后的测谎阶段使用有反馈的ERP测谎范式,以反馈的形式告知被试测谎结果（“+0.5”或“-2”,分别代表“撒谎逃过检测”或“撒谎被发现”）时的脑内时程动态变化。结果发现,在反馈出现后的200～300ms时间段,表示“撒谎被抓住”比“撒谎逃过检测”的反馈信息诱发了一个更正性的ERP成分（P200-300）,在300～400ms时间段,两种反馈诱发的ERP成分（P300）没有差异,而在450～500ms时间段, “撒谎逃过检测”比“撒谎被抓住”的反馈信息诱发了一个更负性的ERP成分（N500）,负性反馈没有诱发FRN。这些结果表明：P200-300、P300和N500都是与加工测谎结果信息有关的ERP成分。P200-300可能对测谎结果的效价（正性或负性）敏感;P300可能反映被试对测谎结果主观意义大小的评价;而N500可能反映测谎结果所导致的大脑皮层兴奋程度。     

不同调控方式个体反事实思维上的差异：来自ERP的证据

利用事件相关电位技术(ERP), 采用简单赌博任务范式, 考察具有“评估倾向”和“行动倾向”的两类个体在反事实思维上的差异及其神经电生理证据。行为结果表明：评估倾向的个体比行动倾向的个体产生更强的反事实思维, 两者差异极其显著; 脑电结果表明：(1)在反映结果快速评价的FRN上, 组别主效应显著, 评估倾向的个体所产生的FRN波幅显著大于行动倾向的个体, (2)在P300上, 组别主效应显著, 评估倾向的个体所产生的P300波幅显著大于行动倾向的个体。简而言之, 两种不同调控方式的个体在反事实思维强度上存在着显著差异, 这在FRN和P300上得到了反映, 评估倾向的个体所产生的反事实思维更强, 情绪体验也更加强烈。不同调控方式的个体, 其反事实思维具有不同的特点和不同的大脑活动。     

人际合作与冲突影响博弈决策的结果评价

人际合作与冲突是人际互动的两种主要形式, 在人类社会的发展中有着重要作用。脑成像研究表明, 当个体和人类同伴进行博弈时, 选择合作与选择冲突激活脑区的强度有所不同。但目前尚不清楚, 人际合作与冲突如何影响决策选择之后的结果评价过程。本研究采用Chicken Game任务对此问题进行了探讨, 研究记录了22名健康成人被试与人类同伴进行Chicken Game任务时的脑电活动。结果表明, 反馈负波(FRN)和P300不仅受到结果效价的影响, 同时也受到人际合作与冲突的影响。相对于选择冲突, 个体选择合作时, 输钱和赢钱反馈引发的FRN以及P300波幅差异更大。相关分析表明, RA (被试和解对方进攻)反馈引发的FRN波幅与接受该反馈后下一个trials中和解的选择率(以及总的和解率)呈显著的负相关。上述结果表明, 在社会博弈中, 合作增加了个体对博弈结果的预期, 从而引发更大的FRN效应; 并且合作共赢的结果所具有的物质意义与社会意义, 使其诱发更大的P300波幅。     

反馈负波及其理论解释

反馈负波（feedback related negativity, FRN）是由代表行为错误或失去金钱等负性反馈刺激诱发的一种脑电波成分,出现在刺激呈现后250~300ms左右,偶极子源定位发现这一成分产生于前扣带回附近。对于FRN的功能意义的解释主要有强化学习理论和情绪动机假说,前者认为FRN反映的是神经系统对反馈刺激的认知加工过程,而后者认为FRN反映的是对情绪动机意义的评价过程。两种理论框架下还有一些目前研究仍待解决的问题,可能是未来研究的方向     

阈下情绪反馈对结果评价的影响及其性别差异

本研究用互动的决策游戏和脑电技术考察阈下情绪反馈对结果加工的影响。结果表明输钱相对于赢钱诱发更大的FRN/RewP和更小的P300,同时阈下愤怒反馈可以延缓赢钱之后下一次选择的反应时,并在女性被试中诱发更负的FRN/RewP, 但对反馈相关P300没有显著影响。这些结果说明阈下情绪反馈可影响决策结果评价早期的对刺激动机性意义的快速评估,但对晚期的深度评估没有显著影响,且这种影响在女性被试中更为明显。     

决策过程中参照点效应研究述评

Kahneman和Tversky提出的“参照点效应”概念,对决策者的认知编码和信息整合方式做出了合理的解释,并对传统的理性决策理论提出了挑战。近年来,关于参照点效应的研究也一直受到众多学者的重视。文章系统阐述了参照点效应的相关概念和最新研究进展,并提出了参照点效应未来研究的4个趋势：日益重视多重参照点效应的研究、开始关注动态决策中的参照点变化机制、重视群体决策过程中的参照点效应研究、注重在现实决策任务中验证和发展参照点效应的相关理论     

差距知觉的泛化效应：我和你之间的差距有多大?

当知晓自己和他人的表现,即自己与他人在某方面表现上的差距已经明确时,人们对自我-他人差异的知觉准确吗?本研究发现了差距知觉的泛化效应：人们将自身的绝对表现(自己的表现与零相比的结果)泛化到对自身相对表现(自己与他人相比的结果)的判断上。在7个研究中, 被试(N = 2766)得知自己的绝对表现和相对于他人的表现,并判断自己与他人之间的差距。结果显示,绝对获益时,人们在相对获益时感知到的自我-他人差距大于相对损失时;绝对损失时,人们在相对获益时感知到的自我-他人差距小于相对损失时;当泛化难以进行时,上述效应消失。研究揭示了差距知觉的泛化效应及其联结机制。     

Communicative functions of directional verbal probabilities: Speaker’s choice,listener’s inference,and reference points

Verbal probabilities have directional communicative functions, and most can be categorized as positive (e.g., “it is likely”) or negative (e.g., “it is doubtful”). We examined the communicative functions of verbal probabilities based on the reference point hypothesis According to this hypothesis, listeners are sensitive to and can infer a speaker’s reference points based on the speaker’s selected directionality. In four experiments (two of which examined speakers’ choice of directionality and two of which examined listeners’ inferences about a speaker’s reference point), we found that listeners could make inferences about speakers’ reference points based on the stated directionality of verbal probability. Thus, the directionality of verbal probabilities serves the communicative function of conveying information about a speaker’s reference point.     

Semantic congruity effects and theories of the comparison process.

Two experiments requiring comparisons of point locations on the line demonstrate that the magnitude of the response-time-based congruity effect parallels the form of the macro and the micro speed-accuracy trade-off function. This is predicted from the evidence accrual class of theories but is contrary to either the propositionally based semantic coding theory or the expectancy view. Very large accuracy-based congruity effects with comparisons of point locations in the plane are evident. Congruity effects arise because the duration of each evidence accrual is increased and the quality of the information is reduced as the distance of the stimulus representations from the instruction-activated reference point increases. This evidence accrual view is extended to account for the properties of perceptual and symbolic comparisons.     

Perceived velocity as a function of reference mark density

The effect on apparent visual speed of varying the density of stationary reference marks evenly distributed along the path of motion of a point of light was measured using tactile comparison motion. The sensitivity of the tactile method of measuring visual speed was supported by the finding that the tactile measures increased with each increase in physical speed of the point of light, other factors held constant. This procedure was applied in two experiments to visual displays in which the physical speed, extent of motion, and number and density of reference marks was varied. Only reference mark density, in addition to physical speed, was found to be a signficant (and robust) factor in determining perceived speed. The effect of reference mark density is explained in terms of the increasing contribution of relative motion cues to the perception of visual speed as a funciton of the average separation (or average adjacency) of the moving point from surrounding reference marks.     

风险决策中的双参照点效应

以预期理论为代表的决策理论认为, 决策者自身的损益状态对风险决策有重要作用, 因此, 将决策者的现状定义为个人参照点。它决定了决策情境是个人获益还是个人损失。个人参照点直接关乎决策者实际的得失, 具有直接性、真实性和绝对性的特征。然而, 社会比较理论认为, 与他人的比较结果同样对风险决策具有不可忽视的意义。因此, 将他人的状态定义为社会参照点。自身的现状与他人状态相比较的结果决定了决策情境是社会获益还是社会损失。社会参照点无关决策者的实际得失, 具有间接性、假设性和相对性的特征。社会参照点通过自我概念、情绪、认知等路径作用于风险决策。更为重要的是, 社会参照点和个人参照点同时存在于风险决策过程中, 决策者对两者的心理感受和行为倾向具有相似性, 因此两者将共同影响决策者的风险选择。基于此, 本文提出风险决策中的双参照点效应。有关双参照点对风险决策过程的影响机制还需进一步的探讨。     

Turning configural processing upside down: part and whole body postures

Like faces, body postures are susceptible to an inversion effect in untrained viewers. The inversion effect may be indicative of configural processing, but what kind of configural processing is used for the recognition of body postures must be specified. The information available in the body stimulus was manipulated. The presence and magnitude of inversion effects were compared for body parts, scrambled bodies, and body halves relative to whole bodies and to corresponding conditions for faces and houses. Results suggest that configural body posture recognition relies on the structural hierarchy of body parts, not the parts themselves or a complete template match. Configural recognition of body postures based on information about the structural hierarchy of parts defines an important point on the configural processing continuum, between recognition based on first-order spatial relations and recognition based on holistic undifferentiated template matching.     

A multisensory interaction effect in the conceptual realm of time

Recent studies on the conceptualization of abstract concepts suggest that the concept of time is represented along a left-right horizontal axis, such that left-to-right readers represent past on the left and future on the right. Although it has been demonstrated with strong consistency that the localization (left or right) of visual stimuli could modulate temporal judgments, results obtained with auditory stimuli are more puzzling, with both failures and successes at finding the effect in the literature. The present study supports an account based on the relative relevance of visual versus auditory-spatial information in the creation of a frame of reference to map time: The auditory location of words interacted with their temporal meaning only when auditory information was made more relevant than visual spatial information by blindfolding participants.     

Viewpoint alignment and response conflict during spatial judgment

Spatial judgment (e.g., identifying the relative location, such as left or right, of a target) from a reference point becomes more difficult with increasing disparity between the relevant allocentric viewpoint and the observer-centered viewpoint. The viewpoint alignment hypothesis suggests that this misalignment effect is due to a realignment process that reconciles two viewpoints, implying that providing an advance cue for a viewpoint should facilitate the subsequent judgment. We examined whether advance viewpoint information can reduce the misalignment effect and whether the misalignment effect reflects response conflict, as well as realignment of viewpoints. In Experiment 1, the misalignment effect decreased with advance viewpoint information, suggesting that the misalignment effect indeed reflects viewpoint realignment. In Experiment 2, the misalignment effect was greater with spatial response codes that might conflict with the spatially arranged response keys than with arbitrary responses with no such conflict. These results suggest that the misalignment effect may arise from both viewpoint realignment and response conflicts.