启动效应的脑机制:表征锐化和反应学习

启动效应通常伴随着相关脑区的神经活动的减少,这就是重复抑制现象;它已经成为探讨启动效应脑机制的关键。表征锐化和反应学习是近年来被广泛探讨的理论,它们分别从客体表征和反应生成两方面解释了重复抑制的成因以及重复抑制与行为改善之间的关系。本文围绕这两个理论,结合最近的研究,探讨了它们各自所对应的神经机制;进而讨论了它们各自的局限性以及未来研究的方向;另外,进一步阐述了启动效应脑机制的研究对脑成像和心理学研究带来的问题和挑战。     

时序知觉重复启动效应的作用机制

先前研究发现,时序判断任务在启动的靶刺激先出现时出现了重复启动效应的反转,这是以往的理论所不能单独解释的。通过两个实验对我们提出的双加工表征匹配调节假说加以实证检验,实验结果支持了该假说。因此,双加工表征匹配调节假说能较完整地综合解释时序知觉重复启动效应的作用机制     

任务切换中的反应重复效应

在任务重复试次中反应的重复对反应有促进作用,而在任务切换试次中反应的重复对反应有阻碍作用,此现象即为反应重复效应（response repetition effects, RRE）。RRE普遍存在不同任务切换范式中,是一种抽象反应编码重复效应,受刺激效价和一致性、反应编码重复度和准备时间等因素影响。其理论解释主要有重构论、启动-抑制论、以及情境检索说。现有研究初步表明前额叶皮层是RRE的关键脑区,但RRE的认知神经机制及理论解释还有待进一步探讨。     

负启动研究与有关理论

该文主要从三个方面来回顾负启动的研究 :负启动与选择注意的关系 ;早期以抑制为主导的负启动研究成果 ,包括抑制的功能、负启动的时间历程、加工位置与个体差异以及实验情景和策略对负启动的影响 ;负启动的理论解释 ,包括干扰项抑制假说、情景提取解释和短暂辨别理论     

重复启动对时序知觉的影响

在时序判断任务中,重复启动导致被试把启动的靶刺激知觉为先出现的。知觉加工增强观和决策反应偏向观都试图解释其机制,但仍存在争议。本研究采用图形材料,通过三个实验系统考察了重复启动对时序知觉的影响。实验结果显示,启动和指导语都具有显著效应。这说明,重复启动对时序知觉的影响涉及知觉加工和决策水平两个方面。实验还首次发现,在启动的靶刺激先出现时发生了重复启动效应的反转。最后,研究提出了双加工表征匹配调节假说,用以综合解释目前的研究结果     

负启动研究与有关理论

该文主要从三个方面来回顾负启动的研究：负启动与选择注意的关系：早期以抑制为主导的负启动研究成果,包括抑制的功能、负启动的时间历程、加工位置与个体差异以及实验情景和策略对负启动的影响：负启动的理论解释,包括干扰项抑制假说、情景提取解释和短暂辨别理论。     

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。     

负启动效应的认知神经科学研究

近几年,对负启动效应的神经机制研究发现,干扰项抑制与情节提取都是引起负启动的原因,究竟哪种机制起主要作用与实验任务有很大的关系。从现有的研究结果来看,位置负启动与前额皮层有关,EPR上表现为P1和N1波幅减小或N2波幅的增大,支持抑制机制。特性负启动P3成分仍存在不一致的结果,脑区的广泛激活模式使得研究者越来越倾向采取整合的观点。     

句法启动的产生机制

句法启动是指个体在产生和理解句子时,倾向于重复使用刚刚加工过的句法结构。本文梳理了句法启动研究在句法启动的实质（语义的还是句法的）、驱动机制（是词汇驱动的还是词汇独立的）、以及时间进程（激活、内隐学习还是双机制理论）等方面的最新进展,发现以下结论：语义对语言产生中的句法启动起着重要作用,但对语言理解中的句法启动作用不明显;语言产生中的句法启动不依赖于词汇重叠,而语言理解中的句法启动大部分是词汇驱动的;激活说能解释语言理解中的句法启动,内隐学习说能够解释相对持久的语言产生中的句法启动现象,双机制理论则可以揭示语言理解中相对持久的句法启动现象。同时指出,以汉语为材料以及通过优化研究设计、丰富研究方法手段等可以深化研究。     

安全基地启动及其脑机制

近几年,安全基地启动已成为拓展依恋理论的重要实验方法。安全启动能够改善情绪及情绪调节策略、增进人际关系、促进自我实现和利他等。安全启动下,研究者得以考察成人依恋与母婴依恋的神经基础及它们之间的区别与联系。该文分析了安全启动实验的不足,如生态效度和重复率不高,应用范围局限,缺乏启动效应持续性的研究等。未来的安全启动研究应突破现有实验室情境研究局限,拓展应用领域,加强对其心理机制与神经机制的探讨等。     

情绪启动：一次阈上与阈下启动研究的实验报告

本文将情绪图片作为启动刺激,分别以阈上和阈下的方式呈现,采用主观情绪自我评定量表和投射问卷检验情绪启动效应.结果发现阈上情绪诱发以消极情绪明显且宜以自我评定方法检验,而阈下情绪启动积极情绪效应优于消极情绪启动且宜用投射检验.     

情绪启动与语义启动的比较

情绪启动与语义启动发生时孰先孰后、进行中独立平行还是交互作用、效应上孰强孰弱,还存在较大争议.这些争议的本质涉及到人脑中情绪和认知这两大基本系统的关系认识问题.通过行为观察与事件相关脑电位技术结合,在同一个实验中设置情绪启动、语义启动两种情境,并匹配可能影响这两种启动效应的因素,如信息强度、启动刺激和靶刺激的信息关联程度等,然后系统性变化启动刺激呈现的时间、SOA、实验任务等,并逐步加入被试的年龄、性别、学科专业、认知风格、情绪易感性等个体差异变量,可望直接而系统地澄清争议,深层次揭示情绪信息流与语义信息流的加工特点,并进而揭示人脑情绪系统与认知系统功能与机制的发展规律.     

高频靶词情绪启动的反转效应

实验采用词-词情绪启动范式,在SOA 5个水平上以高频情绪词为靶词,考察情绪启动的反转效应。结果在SOA各个水平上均发现反转效应,即被试对与启动刺激效价一致的靶刺激的反应较慢,而对与启动刺激效价不一致的靶刺激的反应较快。实验结果支持情绪转换模型和快速-准确策略理论。     

重复启动条件下语义启动效应减少的机制

采用重复启动范式探讨语义启动效应减少的机制。结果发现,在SOA为短的167ms条件下,重复/相同和重复/相关的启动效应无差异,且重复/相关启动并未导致语义启动效应的减少;而在SOA为长的1200ms条件下,重复/相同和重复/相关的启动效应差异显著,且重复/相关启动导致了语义启动效应的减少,而重复/相同未导致语义启动效应的减少。在抵消了期望和消退的作用后,在SOA为1200ms条件下所得到的重复/相同和重复/相关启动效应的差异,是由于扩散受到了阻碍而导致的。这一结论支持了激活扩散是有一定条件的观点。     

Sublimal Visual Priming

Masked pictures of objects were flashed so briefly that only 13.5% of them could be named. Forced-choice accuracy for the unidentified objects was at chance. When the pictures were shown again, about 15 min and 20 intervening trials later, without any indication of possible repetitions, naming accuracy increased to 34.5%. The priming was completely visual, rather than semantic or verbal, as there was no priming of same-name, different-shape images. This is the first demonstration of facilitatory visual recognition priming by unidentified pictures when the subject could not anticipate if, when, or where the previously unidentified picture was to be shown again. A change in the position of the object reduced but did not eliminate the priming, allowing a speculation that the locus of subliminal visual priming is at an intermediate stage in the ventral cortical pathway for shape recognition.     

情绪启动研究

情绪启动研究是揭示情绪——认知关系的有效途径。该文介绍了情绪启动范式的特点和变迁、情绪启动效应的可能表现及其理论解释,对其应用基础研究作了粗略的设想。     

阈上/阈下呈现OH投射卡的情绪启动效应研究

分别在阈上/阈下的条件下呈现OH投射卡,探究两种情况下是否能启动情绪。采用阈上和阈下启动实验,以正确率和反应时为因变量,检验阈上、阈下的情绪启动效果。阈上启动实验中,被试对OH卡中积极和消极、中性材料的反应时有显著差异,正确率没有显著差异。阈下启动实验中,被试对消极和积极、中性材料在反应时和正确率上均存在显著差异。结果表示:(1)阈上呈现OH投射卡,OH卡中的积极情绪效价的图片和词汇能够启动情绪;(2)阈下呈现OH投射卡,OH卡中的消极情绪效价的图片和词汇能够启动情绪。     

Priming involuntary autobiographical memories

Involuntary autobiographical memories occur frequently in daily life and are usually triggered by cues in one's environment. This study investigated the possibility that priming plays a role in the production of involuntary memories. In Study 1, participants recorded their involuntary memories in a diary for 14 days and then completed a questionnaire assessing their cognitive activity during the recording period. Participants indicating frequent thought about significant others on the questionnaire showed significantly more involuntary memories related to such individuals than a control group. In Studies 2 and 3, participants recorded their involuntary memories in diaries for 14 days and were primed with recall sessions in the laboratory during that period (recalling episodes from high school, Study 1, the past year, or ages 13-16, Studies 2 & 3). The results of both studies showed significant priming effects in the involuntary memories of participants for all of the periods primed. The possibility that priming plays a significant role in the daily production of involuntary memories is discussed.     

Priming of emotion recognition

Four experiments investigated priming of emotion recognition using a range of emotional stimuli, including facial expressions, words, pictures, and nonverbal sounds. In each experiment, a prime-target paradigm was used with related, neutral, and unrelated pairs. In Experiment 1, facial expression primes preceded word targets in an emotion classification task. A pattern of priming of emotional word targets by related primes with no inhibition of unrelated primes was found. Experiment 2 reversed these primes and targets and found the same pattern of results, demonstrating bidirectional priming between facial expressions and words. Experiment 2 also found priming of facial expression targets by picture primes. Experiment 3 demonstrated that priming occurs not just between pairs of stimuli that have a high co-occurrence in the environment (for example, nonverbal sounds and facial expressions), but with stimuli that co-occur less frequently and are linked mainly by their emotional category (for example, nonverbal sounds and printed words). This shows the importance of the prime and target sharing a common emotional category, rather than their previous co-occurrence. Experiment 4 extended the findings by showing that there are category-based effects as well as valence effects in emotional priming, supporting a categorical view of emotion recognition.     

Priming involuntary autobiographical memories

Involuntary autobiographical memories occur frequently in daily life and are usually triggered by cues in one's environment. This study investigated the possibility that priming plays a role in the production of involuntary memories. In Study 1, participants recorded their involuntary memories in a diary for 14 days and then completed a questionnaire assessing their cognitive activity during the recording period. Participants indicating frequent thought about significant others on the questionnaire showed significantly more involuntary memories related to such individuals than a control group. In Studies 2 and 3, participants recorded their involuntary memories in diaries for 14 days and were primed with recall sessions in the laboratory during that period (recalling episodes from high school, Study 1, the past year, or ages 13–16, Studies 2 & 3). The results of both studies showed significant priming effects in the involuntary memories of participants for all of the periods primed. The possibility that priming plays a significant role in the daily production of involuntary memories is discussed.