创伤后应激障碍的双重表征理论及其进展

创伤后应激障碍(PTSD)的双重表征理论认为创伤引起了可回忆的言语记忆和可回忆的情境记忆两类记忆。这两类记忆能够解释PTSD,比如再现创伤和情绪加工。创伤的情绪加工可能合出现成功完成、慢性加工和过早抑制加工三个结果。最后本文讨论了该理论在研究设计、临床实践和解释实验数据方面的应用。     

不同语义水平下参照方式、情绪效价和特质评价对记忆的影响

为了探索影响记忆的深层次因素及其作用机制,采用内隐实验范式,考察了不同语义水平下参照方式、情绪效价和特质评价对记忆的影响。结果发现,参照方式、情绪效价和特质评价分别对记忆产生了显著的影响;在不同语义水平下,自我相关的特质词和非特质词的记忆优势表现在不同的再认提取阶段;个体对自我相关的消极词表现出显著的记忆优势;参照方式、情绪效价和特质评价的交互作用不显著。结果表明,参照方式、情绪效价和特质评价是对记忆产生影响的独立因素,但参照方式对记忆的影响受到情绪效价和特质评价的制约。     

情绪记忆的神经基础

情绪记忆具有强烈、持久的特点,在记忆中具有优势地位。杏仁核是情绪记忆的关键脑区,其外侧核被认为是情绪回路建立的中心部位。恐惧条件反射是情绪记忆,特别是情绪回路研究的有效手段。情绪记忆的编码,储存与提取受到杏仁核与各相关脑区共同影响,其中激素调节在这些过程中发挥重要作用。文中结合最新的研究成果对情绪记忆的神经机制进行讨论     

创伤后应激障碍中的非适应性泛化现象

过度泛化现象是区分普通心理问题和严重心理问题的重要指标。创伤后应激障碍(posttraumatic stress disorder, PTSD)患者在创伤事件后会出现非适应性的泛化。现有研究结果表明非适应性泛化(maladaptive generalization)可能是PTSD发生发展的一个重要因素, 但也有研究支持PTSD是导致了泛化从适应性向非适应性化转变的原因。虽然泛化现象的变化与PTSD症状的发展有相同趋势, 且具有共同的生理基础：记忆相关神经结构, 但二者之间的关系尚无明确定论。阐明PTSD与非适应性泛化之间的关系对PTSD的预测、诊断和治疗均有推进作用。     

情绪对项目记忆和来源记忆的影响

最近几十年以来, 情绪对记忆的影响越来越受到认知心理学家的关注。本文总结了我在中科院心理研究所师从傅小兰研究员攻读博士学位期间所开展的主要研究工作。我的研究以中文词语为学习材料, 分别考察了在编码过程中和编码结束后诱发情绪对项目记忆和来源记忆的影响。当情绪在编码阶段被诱发, 主要的研究发现如下：1)负性情绪增强自由回忆, 但正性情绪只呈现出增强自由回忆的趋势。2)负性情绪降低总体再认记忆, 但正性情绪对总体再认记忆没有影响。此外, 正性和负性情绪均不影响“记得”反应的正确率; 然而, 负性情绪降低了“知道”反应的正确率, 正性情绪对“知道”反应的正确率没有影响。3)正性和负性情绪均对来源记忆(即对词语字体颜色的记忆)没有影响。当情绪在编码结束后被诱发, 主要的研究发现如下：1)对女性被试而言, 负性情绪增强了项目记忆的巩固, 然而, 对男性被试而言, 正性和负性情绪均不影响项目记忆的巩固。2)无论对男性还是女性被试, 正性和负性情绪对来源记忆的巩固均没有影响。本研究的上述发现对建立情绪和记忆的关系具有理论意义, 对如何在教学情境中如何利用情绪诱发促进学生的记忆巩固也具有现实指导意义。     

调控去甲肾上腺素能系统对防治创伤后应激障碍的影响

个体经历严重创伤性事件后可能会形成创伤后应激障碍(posttraumatic stress disorder, PTSD)。在创伤经历中形成的情绪记忆是以后发展为PTSD的重要病理机制。PTSD的形成涉及到情绪记忆的过度巩固, 而去甲肾上腺素能神经信号可增强情绪记忆的巩固和再巩固。因此, 在创伤记忆的巩固和再巩固期间阻断去甲肾上腺素能神经信号, 而在创伤记忆的消退期间增强去甲肾上腺素能神经信号, 可能会破坏和或抑制病理性的情绪记忆, 从而预防或治疗PTSD。     

记忆活动中情绪调节的效果和认知神经机制

情绪对记忆的促进作用, 已得到了大量研究的证实。但是, 情绪对记忆的损害作用还没有得到一致的研究结果。情绪诱导的记忆损害的条件和机制还没有得到很好的确认和解释。并且, 在证实了情绪对记忆的影响之后, 一个更具有现实意义的问题是, 人类能够在多大程度上调控情绪对记忆的影响呢？虽然已有的情绪调节研究对一些重要的情绪调节策略如认知重评和抑制进行了较多的探讨, 考察了情绪调节对情绪事件记忆的影响。但是, 关于情绪调节是否可以有效地调整情绪唤醒对中性项目记忆的影响, 目前只有少量的研究。对情绪调节影响记忆的认知神经机制还所知甚少。因此, 本项目拟综合使用行为测量和认知神经科学技术, 在考察情绪唤醒对记忆的损害效应的条件和机制的基础上, 进一步探讨认知重评、抑制和忽视等情绪调节策略调控记忆中的情绪效应的有效性和认知神经机制。研究结果将会有助于对情绪、情绪调节和记忆的关系的理解, 并对促进学生的学习记忆活动有现实意义。     

催产素对学习和记忆的调节效应：来自动物与人类的研究证据

作为一种神经肽, 催产素对于个体社会认知和情绪加工有着非常重要的调节作用, 其中就包括对在人们工作和生活中扮演着关键角色的学习和记忆活动的影响。采用不同模态技术的动物和人类研究一致表明了外源性催产素对于学习和记忆具有重要的调节作用, 这一作用可能是外源性催产素通过与多巴胺奖赏通路、边缘系统等学习和记忆关键脑网络中广泛分布的催产素受体相结合, 进而调整其功能状态实现的; 但与此同时, 催产素对学习和记忆的促进或抑制作用会因实验范式、刺激材料、给药时间、位置和剂量等因素的不同而存在差异。未来需要协同动物和人类研究的各自优势, 采用规范化的实验任务设置和给药程序克服当前该领域的研究局限, 并积极发掘催产素在干预相关精神疾病患者学习和记忆加工缺陷中的应用潜力。     

基于不同情绪的前瞻记忆及TAP效应的影响研究

前瞻记忆是指现在对将来某一段时间要做的行为的记忆。采用情绪图片作为诱发材料,研究了在情绪刺激下前瞻记忆任务以及前瞻记忆TAP效应的影响。结果表明:不同情绪效价主效应显著,正性情绪组成绩显著高于中性情绪组和负性情绪组; 前瞻记忆TAP效应在正性情绪和中性情绪下显著,负性情绪下部分显著; 在不同情绪效价影响下,语义—语义组、语义—知觉组、知觉—知觉组以及知觉—语义组的前瞻记忆成绩差异均存在统计学意义。     

不同情绪调节方式对记忆的影响

个体的情绪调节与其认知的关系是近年来情绪和认知领域中一个重要的前沿研究热点。本研究则通过两个阶段的实验,较系统地探讨了两种情绪调节分类下的四种情绪调节方式（原因调节——评价忽视和评价重视,反应调节——表情抑制和表情宣泄;减弱调节——评价忽视和表情抑制,增强调节——评价重视和表情宣泄）对记忆（视觉和听觉记忆）及记忆评价（即元记忆,视觉和听觉元记忆）的影响。结果表明：(1)评价忽视和评价重视对记忆没有影响;表情抑制和表情宣泄对记忆影响显著（表情抑制影响了听觉记忆,表情宣泄影响了视觉和听觉记忆）;(2)评价忽视、评价重视和表情宣泄对元记忆没有影响;而表情抑制影响听觉元记忆;(3)不同情绪调节方式对记忆的影响无性别和专业上的差异,但对元记忆虽无性别差异上的影响,却存在专业上的差异。总之,个体不同的情绪调节方式会对记忆和元记忆产生不同影响     

Emotional distress and positive and negative memories from military deployment: the influence of PTSD symptoms and time

During military deployment, soldiers are confronted with both negative and positive events. What is remembered and how it affects an individual is influenced by not only the perceived emotion of the event, but also the emotional state of the individual. Here we examined the most negative and most positive deployment memories from a company of 337 soldiers who were deployed together to Afghanistan. We examined how the level of emotional distress of the soldiers and the valence of the memory were related to the emotional intensity, experience of reliving, rehearsal and coherence of the memories, and how the perceived impact of these memories changed over time. We found that soldiers with higher levels of post-traumatic stress disorder (PTSD) symptoms were more affected by both their negative and positive memories, compared with soldiers with lower levels of PTSD symptoms. Emotional intensity of the most negative memory increased over time in the group with highest levels of PTSD symptoms, but dropped in the other groups. The present study adds to the literature on emotion and autobiographical memory and how this relationship interacts with an individual’s present level of emotional distress and the passage of time.     

人类记忆再巩固研究现状及临床应用

巩固的记忆被提取后,进入不稳定状态,再重新稳定下来,这个过程称为记忆再巩固。本文首先阐述人类记忆再巩固主要研究方法和经典范式,梳理记忆再巩固在人类恐惧记忆和情景记忆两个方面的相关研究,并从认知神经科学角度整理记忆再巩固的加工机制。然后总结记忆再巩固应用于创伤性应激障碍和药物成瘾等心理障碍临床治疗的相关文献。最后本文提出未来研究的方向和建议,希冀对人类记忆再巩固的理论研究和临床应用提供新思路。     

Inhibitory control of threat remembering in PTSD

ABSTRACT

Intrusive traumatic recollections suggest an inability in Posttraumatic Stress Disorder (PTSD) to control and notably to inhibit memories for trauma-related information. Supported by inhibitory deficits found on experimental settings in PTSD, memory functioning and memory biases in the disorder were usually explained through inhibitory and control deficits in the processing of trauma-related information. The present study aimed to directly assess this hypothesis by investigating memory control abilities for emotional information in PTSD. For this purpose, 34 patients diagnosed with PTSD were compared to 37 non-PTSD controls on an item-cued directed forgetting paradigm for emotional words combined with a Remember/Know recognition procedure. Results revealed enhanced amounts of Remember recognitions for trauma-related words in PTSD. Moreover, we replicated findings of memory control impairments in the disorder. However, such impairments only occurred for non-trauma-related words. Accordingly, it appeared that PTSD patients presented preserved memory control abilities for trauma-related words, at the expenses of other emotional valences. Surprisingly, PTSD patients presented a preserved ability to control and notably to inhibit their memory functioning for trauma-related material. In addition to potential theoretical and clinical relevance, these results are discussed in the light of resource reallocation hypotheses and vigilant-avoidant theories of information processing in PTSD.     

Autobiographical memory for stressful events: the role of autobiographical memory in posttraumatic stress disorder

To provide the three-way comparisons needed to test existing theories, we compared (1) most-stressful memories to other memories and (2) involuntary to voluntary memories (3) in 75 community dwelling adults with and 42 without a current diagnosis of posttraumatic stress disorder (PTSD). Each rated their three most-stressful, three most-positive, seven most-important and 15 word-cued autobiographical memories, and completed tests of personality and mood. Involuntary memories were then recorded and rated as they occurred for 2 weeks. Standard mechanisms of cognition and affect applied to extreme events accounted for the properties of stressful memories. Involuntary memories had greater emotional intensity than voluntary memories, but were not more frequently related to traumatic events. The emotional intensity, rehearsal, and centrality to the life story of both voluntary and involuntary memories, rather than incoherence of voluntary traumatic memories and enhanced availability of involuntary traumatic memories, were the properties of autobiographical memories associated with PTSD.     

Propranolol and the Prevention of Post-Traumatic Stress Disorder: Is it Wrong to Erase the “Sting” of Bad Memories?

The National Institute of Mental Health (Bethesda, MD) reports that approximately 5.2 million Americans experience post-traumatic stress disorder (PTSD) each year. PTSD can be severely debilitating and diminish quality of life for patients and those who care for them. Studies have indicated that propranolol, a beta-blocker, reduces consolidation of emotional memory. When administered immediately after a psychic trauma, it is efficacious as a prophylactic for PTSD. Use of such memory-altering drugs raises important ethical concerns, including some futuristic dystopias put forth by the President's Council on Bioethics. We think that adequate informed consent should facilitate ethical research using propranolol and, if it proves efficacious, routine treatment. Clinical evidence from studies should certainly continue to evaluate realistic concerns about possible ill effects of diminishing memory. If memory-attenuating drugs prove effective, we believe that the most immediate social concern is the over-medicalization of bad memories, and its subsequent exploitation by the pharmaceutical industry.     

Socioemotional selectivity in older adults: Evidence from the subjective experience of angry memories

Few studies have compared the phenomenological properties of younger and older adults' memories for emotional events. Some studies suggest that younger adults remember negative information more vividly than positive information whereas other studies suggest that positive emotion yields phenomenologically richer memories than negative emotion for both younger and older adults. One problem with previous studies is a tendency to treat emotion as a dichotomous variable. In contrast, emotional richness demands inclusion of assessments beyond just a positive and negative dimension (e.g., assessing specific emotions like anger, fear and happiness). The present study investigated different properties of autobiographical remembering as a function of discrete emotions and age. Thirty-two younger and thirty-one older adults participated by recalling recent and remote memories associated with six emotional categories and completed the Memory Characteristics Questionnaire for each. Results demonstrated that older adults' angry memories received lower ratings on some phenomenological properties than other emotional memories whereas younger adults' angry memories did not show this same pattern. These results are discussed within the context of socioemotional selectivity theory.     

Reducing negative emotional memories by retroactive interference

Because negative emotional memories are often disruptive, we conducted two experiments to reduce these memories by using a retroactive interference (RI) paradigm. In both experiments, participants were presented with highly negative pictures (List 1) followed by highly negative, moderately negative, or neutral pictures (List 2) or a rest period. Then, following a filler task, participants took a surprise free recall test, recalling pictures from List 1 in Experiment 1 and from both List 1 and List 2 in Experiment 2. In both experiments, recall of List 1 was reduced by List 2, indicating that RI was present. Furthermore, in Experiment 1, RI was similar between moderately negative and highly negative List 2 whereas in Experiment 2, RI was greater for highly negative List 2 than moderately negative List 2. These results showed that RI can be used to reduce negative emotional memories by making these memories inaccessible.     

Effects of stress hormones on traumatic memory formation and the development of posttraumatic stress disorder in critically ill patients

A majority of patients after intensive care treatment report traumatic memories from their stay in the intensive care unit (ICU). Traumatic memories can be associated with the development of posttraumatic stress disorder (PTSD) in a subpopulation of these patients. In contrast to other patient populations at risk for PTSD, patients in the ICU often receive exogenously administered stress hormones like epinephrine, norepinephrine, or cortisol for medical reasons and are extensively monitored. ICU patients therefore represent a suitable population for studying the relationship between stress hormones, traumatic memories, and the development of PTSD. Studies in long-term survivors of ICU treatment demonstrated a clear and vivid recall of different categories of traumatic memory such as nightmares, anxiety, respiratory distress, or pain with little or no recall of factual events. The number of categories of traumatic memory recalled increased with the total administered dosages of stress hormones (both catecholamines and cortisol), and the evaluation of these categories at different time points after discharge from the ICU showed better memory consolidation with higher dosages of stress hormones administered. However, the administration of stress doses of cortisol to critically ill patients resulted in more complex findings as it caused a significant reduction in PTSD symptoms measured after recovery. This effect can possibly be explained by a differential influence of cortisol on memory. Increased serum cortisol levels not only result in consolidation of emotional memory but are also known to cause a temporary impairment in memory retrieval which appears to be independent of glucocorticoid effects on memory formation. Disrupting retrieval mechanisms with glucocorticoids during critical illness may therefore act protectively against the development of PTSD by preventing recall of traumatic memories. Our findings indicate that stress hormones influence the development of PTSD through complex and simultaneous interactions on memory formation and retrieval. Our studies also demonstrate that animal models of aversive learning are useful in analyzing and predicting clinical findings in critically ill humans.     

Cognitive avoidance of intrusive memories: recall vantage perspective and associations with depression

Although recent research demonstrates that intrusive memories represent an overlapping cognitive feature of depression and post-traumatic stress disorder (PTSD), there is still a general paucity of research investigating the prevalence and maintenance of intrusive memories in depression. The current study investigated the association between a range of cognitive avoidant mechanisms that characterize PTSD samples (i.e., suppression, rumination, emotional detachment, and an observer vantage perspective) and intrusive memories of negative autobiographical events in relation to dysphoria. Hypotheses were based on the proposition that employment of these cognitive mechanisms would hinder the emotional processing of the negative event, thus contributing to the maintenance of intrusions. Results supported an association between negative intrusive memories, dysphoria, and avoidant mechanisms. Significant differences were also found between field and observer memories and measures of emotional detachment and rumination. Implications relating to intrusive memory maintenance and treatment approaches are discussed.     

Autobiographical memory in posttraumatic stress disorder before and after treatment

Although overgeneral retrieval of autobiographical memories has been repeatedly demonstrated in posttraumatic stress disorder (PTSD), no studies have indexed overgeneral retrieval before and after treatment of PTSD. Autobiographical memory was assessed in PTSD participants (n=20) prior to commencing cognitive behaviour therapy and 6 months after therapy completion. Fifteen participants completed both assessments. Improvement in PTSD symptoms was significantly associated with improved retrieval of specific memories and decreased retrieval of categoric memories in response to positive cues. These data suggest that symptom reduction during treatment of PTSD leads to greater access to specific memories of positive experiences.