急性应激对工作记忆的影响受工作记忆负荷调节:来自电生理的证据

急性应激如何影响工作记忆还不清楚。采用电影片断诱发被试的急性应激或中性状态后,让其完成数字N-back任务并同时记录脑电。结果发现,低负荷工作记忆诱发的P3显著大于高负荷工作记忆;在0-back任务中,急性应激组诱发的P3显著大于控制组;而在2-back任务中,这种差异不显著。这些结果表明急性应激对工作记忆的影响受工作记忆负荷调节,支持了双竞争理论模型。     

急性应激影响工作记忆的生理心理机制

急性应激是机体面对外界环境变化所产生的一系列生理和心理反应, 对认知加工, 尤其是核心的工作记忆能力产生深远影响, 然而以往的研究存在大量不一致的结果。从应激诱发方式、工作记忆加工子成分、个体差异等三个方面系统阐释应激影响工作记忆的生理心理机制, 并结合认知神经机制的框架, 可以更好地理解以往的结果。未来研究应综合考虑应激诱发、认知任务和响应个体等方面的差异对应激带来的影响, 并关注急性应激负面影响的干预与调控。     

重复性急性应激对攻击行为的影响及调控机制

关于急性应激对攻击行为的影响, 现有研究多集中于单次急性应激情境下。然而, 相比单次急性应激, 对重复暴露于同一应激源的研究更能反映人们在现实生活中经历的应激事件。与单次应激不同, 重复性急性应激与应激适应有关, 能够节省资源, 具有很强的进化和适应意义, 但目前关于重复性急性应激对攻击行为的影响却知之甚少。鉴于此, 研究运用事件电位相关技术、鼻喷催产素和催产素受体基因型分析方法, 探讨重复性急性应激对攻击行为的影响及内部机制, 并进一步探讨通过内部和外部调控重复性急性应激反应后攻击行为的变化。     

急性心理性应激对自我参照记忆的影响

已有研究表明急性心理性应激会导致个体的自传体记忆受损,然而急性心理性应激如何影响个体加工当前的自我相关信息,还没有研究结论,本研究旨在丰富和拓展这一领域的研究,从而更加全面深入的了解急性心理性应激对自我相关信息的影响。本研究将自我参照记忆的R/K(记得/知道)范式与特里尔社会应激测试(Trier Social Stress Test:TSST)相结合,考察59名处在不同急性心理性应激状态下的被试自我参照记忆的成绩。结果发现高应激反应组自我参照的R回忆率值显著低于低应激反应组,研究结果发现,被试在特里尔社会应激测试过程中的急性心理性应激反应越强,自我参照的R回忆率越低。结果表明急性心理性应激会抑制个体对当前自我相关信息的加工,削弱了自我参照记忆。     

石杉碱甲对应激诱导的吗啡行为敏感化表达的影响

为探讨石杉碱甲对应激诱导的吗啡行为敏感化表达的影响, 将40只动物随机分为5组: 盐水组、石杉碱甲组、吗啡组、应激组、石杉碱甲+应激组。实验发现, 急性/慢性空瓶应激都能够激发吗啡行为敏感化的表达, 而石杉碱甲能够显著抑制空瓶应激的这种激发作用。经过吗啡点燃后, 急性空瓶应激并不能显著影响动物的行为敏感化, 提示与成瘾性药物的再现相比, 空瓶应激对动物的影响力度较小。研究结果表明, 石杉碱甲能够抑制急性/慢性空瓶应激诱导的吗啡行为敏感化表达, 表明这类胆碱酯酶抑制剂有可能成为治疗药物依赖的潜在药物。     

视觉与言语工作记忆表征对视觉注意的引导

通过三个实验,探讨不同时间进程下视觉和言语工作记忆表征对视觉注意的引导。实验1采用注意引导与注意探测任务同时呈现的范式,探讨不同记忆项与注意项时间间隔(SOA)条件下言语工作记忆表征对视觉注意的引导。结果发现,当SOA较短时言语工作记忆表征对视觉注意有引导效应,而SOA较长时未观察到引导效应;实验2、3采用注意引导任务与注意探测任务分离范式,分别探讨在不同SOA条件下言语和视觉工作记忆表征对视觉注意的引导。结果发现,不同SOA条件下言语和视觉工作记忆表征均能引导视觉注意。研究表明,不同实验范式对言语工作记忆表征对视觉注意的引导有明显影响,视觉比言语工作记忆表征能在更广泛条件下引导视觉注意。     

急性应激损害对威胁刺激的注意解除

急性应激会增强个体对威胁刺激的注意偏向, 但急性应激是增强了对威胁刺激的注意定向还是损害了对威胁刺激的注意解除还不清楚。本研究采用社会评估冷压任务和点探测任务, 结合事件相关电位技术, 考察急性应激对威胁刺激注意偏向影响的认知机制。在进行社会评估冷压任务后, 应激组个体的状态焦虑和皮质醇浓度显著升高。在注意偏向中, 应激组对威胁刺激的注意解除比控制组更慢, 应激组和控制组在对威胁刺激的注意定向上无显著差异。ERP结果上, 威胁刺激诱发应激组比控制组产生了更负的SPCN, 在N2pc上没有显著差异。应激组和控制组皮质醇增量的差异和N2pc、SPCN的组间差异均有显著正相关。这些结果说明, 急性应激增强对威胁刺激的注意偏向是因为其损害个体对威胁刺激的注意解除, 这可能是因为急性应激损害了与注意解除相关的额-顶网络的功能所致。     

急性应激损伤错误监控与错误后调整

生活中, 个体会时时关注自己的行为结果并及时做出调整以适应环境的变化。但在应激下个体能否有效地监控行为并做出适应性调整依然未知。本研究招募了52名男性大学生被试, 将其随机分入应激组与控制组, 采用特里尔社会应激测试(Trier Social Stress Test, TSST)诱发个体的应激反应, 并结合错误意识任务(Error Awareness Task, EAT)探索个体急性应激下的错误监控与错误后调整过程。应激指标的结果显示应激组个体在应激任务后唾液皮质醇、心率、应激感知自我报告和负性情绪均显著高于控制组, 表明急性应激的诱发是成功的。行为结果显示应激组的错误意识正确率显著低于控制组, 错误意识反应时显著短于控制组; 进一步地, 应激组个体在意识到错误之后的试次上正确率显著低于未意识到错误之后的试次, 并且应激组个体在意识到错误之后的试次上正确率低于控制组。结果表明急性应激降低了个体对错误反应的监控水平, 即便在辨别出错误反应的情况下, 个体的行为监控与调节也更差。本研究说明急性应激会损伤行为监控系统, 导致个体的行为适应性下降。     

急性心理应激对不同人格类型大学生TNF-α和IL-6的影响

以56名大学生为研究对象,用艾森克人格问卷（EPQ）进行测试,用公共演讲作为应激源,用放射免疫法测定血清肿瘤坏死因子α（TNF-α）和白细胞介素6（IL-6）的含量,旨在探讨急性心理应激对不同人格类型大学生免疫功能的影响。实验结果发现：与对照组相比,急性心理应激后内向组和情绪稳定组TNF-α的明显升高,其余变化均不显著。这说明急性心理应激引起内向、情绪稳定的个体自然免疫增强的现象较明显,而对外向、情绪不稳定个体的作用不明显。     

急性应激障碍（ASD）研究述评

急性应激障碍是个体在亲历、目击或面临一个对自己或他人具有死亡威胁、严重伤害的创伤事件后的2天至4周内所表现的应激反应。急性应激障碍的症状主要表现为分离、再历、回避和过度警觉。文章回顾了以往的相关研究,从急性应激障碍的测评方法、发生率、与创伤后应激障碍和创伤记忆的关系、心理治疗和干预等方面进行了综述。最后对未来可能的研究方向提出了展望     

The role of stress mindset in shaping cognitive,emotional, and physiological responses to challenging and threatening stress

Background and objectives: Prior research suggests that altering situation-specific evaluations of stress as challenging versus threatening can improve responses to stress. The aim of the current study was to explore whether cognitive, physiological and affective stress responses can be altered independent of situation-specific evaluations by changing individuals’ mindsets about the nature of stress in general.

Design: Using a 2?×?2 design, we experimentally manipulated stress mindset using multi-media film clips orienting participants (N?=?113) to either the enhancing or debilitating nature of stress. We also manipulated challenge and threat evaluations by providing positive or negative feedback to participants during a social stress test.

Results: Results revealed that under both threat and challenge stress evaluations, a stress-is-enhancing mindset produced sharper increases in anabolic (“growth”) hormones relative to a stress-is-debilitating mindset. Furthermore, when the stress was evaluated as a challenge, a stress-is-enhancing mindset produced sharper increases in positive affect, heightened attentional bias towards positive stimuli, and greater cognitive flexibility, whereas a stress-is-debilitating mindset produced worse cognitive and affective outcomes.

Conclusions: These findings advance stress management theory and practice by demonstrating that a short manipulation designed to generate a stress-is-enhancing mindset can improve responses to both challenging and threatening stress.     

任务无关情绪刺激对工作记忆信息更新的影响:来自ERP的证据

任务无关的情绪刺激如何对工作记忆的信息更新过程产生影响还不清楚。本研究采用情绪N-back任务,结合事件相关电位技术调查情绪对工作记忆信息更新的影响。ERP结果显示,在0-back任务中,负性分心物诱发的P3显著小于中性分心物,表明其干扰了工作记忆信息更新过程;而在2-back任务中,负性分心物诱发的P3与中性分心物没有显著差异,表明其未对信息更新表现出干扰效应。该结果支持了情绪与认知加工的双竞争模型。     

不同人际情境影响工作记忆的初探

采用信任博弈任务创设人际信任、人际背叛及背叛后利他惩罚三种人际情境,探讨三种人际情境对不同任务难度工作记忆的影响。结果发现：（1）随着工作记忆的难度增加,三组正确率均显著下降。在低难度任务中,人际信任组和背叛后利他惩罚组正确率均高于人际背叛组;中等难度任务中,人际信任组正确率高于背叛后利他惩罚组和人际背叛组;高难度任务中,三组正确率无明显差异;（2）随着工作记忆的难度增加,三组反应时均显著增加。低难度任务中,人际信任组、背叛后利他惩罚组反应时均低于人际背叛组;中等难度和高难度任务中,三组反应时无明显差异。结论：人际信任、人际背叛及背叛后利他惩罚对工作记忆有不同作用。     

The role of stress mindset in support provision

To better understand the antecedents of support provision within relationships, this study examined the potential role of a novel individual difference; spouses' stress mindset (i.e., beliefs about whether stress‐is‐enhancing or stress‐is‐debilitating). As individuals with a stress‐is‐enhancing mindset often underestimate other's stress, we hypothesized that those with a stress‐is‐enhancing mindset will generally provide less and worse support compared to individuals with a stress‐is‐debilitating mindset. The results revealed few significant associations and the associations that were significant were contrary to predictions. For example, wives with a stress‐is‐enhancing mindset provided more support, and husbands who perceived their partner as having a more stress‐is‐enhancing mindset provided better support. Further research is needed to replicate these results and determine whether stress mindset has interpersonal consequences.     

Understanding the role of mind wandering in stress-related working memory impairments

Mind wandering has been identified as a possible cause for stress-related working memory (WM) task impairments following laboratory stressors. The current study attempted to induce mind wandering regarding negative, positive, or neutral events using an expressive writing task and examined the impact on WM task performance. We examined the role of mind wandering in understanding the impact of life stress on WM. Additionally, we explored the role of thought suppression on the relationship between mind wandering and WM. One hundred and fifty participants completed WM measures before (Time 1) and after (Time 2) the writing manipulation. The writing manipulation did not alter mind wandering or WM task performance. Time 1 WM predicted mind wandering during the Time 2 WM task, which subsequently predicted poorer Time 2 WM task performance. The impact of daily life stress on WM was mediated by mind wandering. Trait levels of thought suppression moderated the impact of mind wandering on WM. Specifically, higher levels of suppression resulted in stronger negative impact of mind wandering on WM task performance. Findings are discussed in terms of the impact of mind wandering on WM task performance.     

短时存贮与复述动态分离的ERP证据

工作记忆参与信息的短时贮存和操作加工。为了分离参与词语短时存贮与复述的脑区及其时间过程,测量并比较了14名正常青年被试进行汉字2-back、0-back和复述任务时的事件相关电位(ERPs)。结果发现,2-back任务减复述任务在头皮后部出现差异波N430,可能反映了信息的短时存贮及其时间进程。2-back任务减0-back任务在头皮前部得到的持续负成分SNC可能是复述加工的动态指标。SNC和N430持续时间的重叠提示,大脑额叶和后部区域分别参与信息的复述和短时存贮,两者的动态分离加工可能是工作记忆中暂时保持的神经基础。     

Novel n-back spatial working memory task using eye movement response

We created a novel eye movement version of the n-back task to measure spatial working memory (WM). Rather than one continuous trial, discrete trials were presented in order to develop a simpler WM task. In Experiment 1, we varied the visibility of the final stimulus to maximize the difference in performance between 0-back and 1-back tasks (WM effect). In Experiment 2, we administered the optimized task to children. In Experiment 3, we further simplified the task. Both adults and children easily completed our task, displaying significant WM effects. Further, similar WM effects were obtained in our original and simplified n-back spatial WM tasks, demonstrating flexibility. Because WM deficits are often an early feature of disease and a marker of disease progression, our saccadic measure of spatial WM may be particularly useful in hard-to-test populations, such as patients and children, and may have application in brain-imaging studies that require discrete trials.