轻度阿尔茨海默症患者的前瞻记忆

轻度阿尔茨海默症往往伴随着不同程度的前瞻记忆衰退。已有研究以轻度阿尔茨海默症与前瞻记忆衰退的关联程度为主线, 对比了这一关联与“其他认知缺陷疾病-前瞻记忆衰退”、“轻度阿尔茨海默症-回溯记忆衰退”以及“轻度阿尔茨海默症-遗传表达”这三种关联的类似程度。此外, 也有研究涉及到了如何促进轻度阿尔茨海默症患者的前瞻记忆。将来的研究应引入病情程度、前瞻记忆任务类型等变量, 深入探讨轻度阿尔茨海默症与前瞻记忆衰退的关联, 并使用ERP、fMRI等神经生理技术确定轻度阿尔茨海默症患者前瞻记忆衰退的机制。     

图形项目记忆与位置来源提取的ERP研究

采用事件相关电位（ERP）方法研究大学生图形项目记忆与位置来源提取新/旧效应的时、空分布特征。学习屏幕左侧（或右侧）呈现的图形后在屏幕中央呈现某一测验项目（已学图形或新图形）,对受试者进行两类测验：其一是判断该项目是否已学过;其二是将从某侧学过的测验项目判断为目标,而将其它测验项目判断为非目标的来源测验（排除任务）。实验结果表明：图形位置来源提取比项目再认新/旧效应的头皮分布更广,持续时程更长;与前人相同实验范式的研究结果相比,本研究位置来源提取效应的头皮分布范围较广;非目标-旧图形与目标图形新/旧效应的头皮激活程度不同。上述结果说明：图形位置来源提取比项目再认激活的大脑区域更多,这与双重加工模型的观点一致;实验范式和来源知觉的特性共同调节来源记忆新/旧效应的时、空分布特征;意识水平对来源信息提取的新/旧效应存在一定的影响     

The effect of cognitive reappraisal on long‐term emotional experience and emotional memory

One's ability to properly regulate emotion is critical to psychological and physical well‐being. Among various strategies to regulate emotion, cognitive reappraisal has been shown to modulate both emotional experience and emotional memory. However, most studies of reappraisal have focused on reappraisal of negative situations, with reappraisal of positive emotion receiving considerably less attention. In addition, the effects of reappraisal on emotional reactions to stimuli are typically only assessed either immediately or after a short delay, and it remains unclear whether reappraisal effects persist over longer time periods. We investigated the effect of cognitive reappraisal on emotional reactions and long‐term episodic memory for positive and negative stimuli. Men and women viewed emotionally negative, positive, and neutral pictures while they were instructed to either increase, decrease, or maintain the initial emotional reactions elicited by the pictures. Subjective ratings of emotional valence and arousal were assessed during the regulation task and again after 1 week. Memory for the pictures was assessed with free recall. Results indicated that pictures accompanied by instructions to increase emotion were better recalled than pictures reappraised to decrease emotion. Modulation of emotional arousal elicited by stimuli persisted over a week, but this effect was observed only for men. These findings suggest that cognitive reappraisal can have long‐lasting effects on emotional reactions to stimuli. However, the sex differences observed for the effects of reappraisal on emotional reactions highlight the importance of considering individual differences in the effects of regulation.     

中文阅读中长距离回视引导机制的眼动研究

从记忆的角度,探讨中文阅读中长距离回视的引导机制。采用眼动实验,操纵了回视条件(实验1)、回视可见性(实验2)、目标词位置及词频变量。结果发现:与不阅读组相比,阅读组的最初回视误差更小,定位效率更高;与可见组相比,不可见组累积回视距离更大,且难以正确定位目标;目标词位置主效应显著,而词频主效应不显著。结果表明,回视具有空间选择性,最初的回视由空间记忆引导,最初回视后的修正眼跳在文本可见情况下才能正常进行,而词频这一言语属性对回视没有显著影响,本研究结果支持了空间编码假设。     

目标探测对记忆提取的影响

采用经典的"学习–再认"范式,在测验阶段设置了目标探测的干扰任务,通过比较目标探测和分心拒绝是否会对记忆提取产生不同的影响,以进一步探讨提取干扰与再认记忆之间的关系。结果发现,无论对目标进行显性(实验1)还是隐性(实验2)的探测反应,目标探测下旧词的再认反应均要比分心拒绝下更优,表明外显记忆的提取也会受到注意资源的调节。但更为重要的是,在辨别力指数(d′)及判断标准(C)上的差异分析发现,目标探测并没有提高被试的再认水平,而是降低了被试的判断标准,使得被试在目标探测条件下更容易对词做出"旧"反应。这种反应倾向与目标探测的动作反应方式无关,也不受词汇的编码加工水平深浅的调节。由此可见,外显记忆提取并非完全的"自动化加工",仍会受到注意资源的调节。     

视觉工作记忆回溯线索效应的产生机制：认知阶段分离

以往研究关于视觉工作记忆回溯线索效应的产生机制主要存在5种假设,目前依然存在争议。本研究通过改进前人研究实验范式,采用包含内源性回溯线索的颜色回忆报告范式,进一步对这5种假设进行检验。在实验1中,我们调控了线索与探测阵列之间的时间间隔,发现不同时间间隔不影响无线索条件的行为表现,而在正常线索条件中被试的记忆精度以及能记住的项目数量均优于无线索条件;在实验2中,我们对回溯线索伴随的干扰刺激类型进行控制,结果显示,在不同条件下记忆精度不存在差别,但当回溯线索伴随干扰刺激呈现时,被试能记住的项目数量会被降低,降低程度受干扰刺激的类型调制;在实验3中,我们对伴随回溯线索的干扰刺激的呈现时间进行控制,发现虽然回溯线索效应仍然存在,但干扰刺激的呈现时间不会影响效应程度。研究结果表明,回溯线索的出现使得被试能够在决策加工前完成内部注意资源的再分配,从而避免了同时进行这两种认知加工与记忆表征维持本身竞争认知资源。本研究为认知阶段分离假设提供了支持证据,对解决回溯线索效应产生机制的争议以及理解内部注意与视觉工作记忆的关系有重要意义。     

不同注意对视觉工作记忆外部特征绑定的影响

采用变化觉察范式,在工作记忆保持阶段插入客体特征辨别或视觉搜索次任务,探讨基于客体的注意和基于空间的注意对视觉工作记忆外部特征绑定表征的影响。结果发现,与单特征相比,两类次任务均对外部特征绑定的记忆成绩损耗更大。这表明视觉工作记忆中外部特征绑定的表征比单特征消耗更多基于客体的注意和更多基于空间的注意。     

Why Higher Working Memory Capacity May Help You Learn: Sampling,Search, and Degrees of Approximation

Algorithms for approximate Bayesian inference, such as those based on sampling (i.e., Monte Carlo methods), provide a natural source of models of how people may deal with uncertainty with limited cognitive resources. Here, we consider the idea that individual differences in working memory capacity (WMC) may be usefully modeled in terms of the number of samples, or “particles,” available to perform inference. To test this idea, we focus on two recent experiments that report positive associations between WMC and two distinct aspects of categorization performance: the ability to learn novel categories, and the ability to switch between different categorization strategies (“knowledge restructuring”). In favor of the idea of modeling WMC as a number of particles, we show that a single model can reproduce both experimental results by varying the number of particles—increasing the number of particles leads to both faster category learning and improved strategy‐switching. Furthermore, when we fit the model to individual participants, we found a positive association between WMC and best‐fit number of particles for strategy switching. However, no association between WMC and best‐fit number of particles was found for category learning. These results are discussed in the context of the general challenge of disentangling the contributions of different potential sources of behavioral variability.     

Keeping the Result in Sight and Mind: General Cognitive Principles and Language‐Specific Influences in the Perception and Memory of Resultative Events

We study how people attend to and memorize endings of events that differ in the degree to which objects in them are affected by an action: Resultative events show objects that undergo a visually salient change in state during the course of the event (peeling a potato), and non‐resultative events involve objects that undergo no, or only partial state change (stirring in a pan). We investigate general cognitive principles, and potential language‐specific influences, in verbal and nonverbal event encoding and memory, across two experiments with Dutch and Estonian participants. Estonian marks a viewer's perspective on an event's result obligatorily via grammatical case on direct object nouns: Objects undergoing a partial/full change in state in an event are marked with partitive/accusative case, respectively. Therefore, we hypothesized increased saliency of object states and event results in Estonian speakers, as compared to speakers of Dutch. Findings show (a) a general cognitive principle of attending carefully to endings of resultative events, implying cognitive saliency of object states in event processing; (b) a language‐specific boost on attention and memory of event results under verbal task demands in Estonian speakers. Results are discussed in relation to theories of event cognition, linguistic relativity, and thinking for speaking.     

Cognitive Offloading: Structuring the Environment to Improve Children's Working Memory Task Performance

Research has shown that adults can engage in cognitive offloading, whereby internal processes are offloaded onto the environment to help task performance. Here, we investigate an application of this approach with children, in particular children with poor working memory. Participants were required to remember and recall sequences of colors by placing colored blocks in the correct serial order. In one condition the blocks were arranged to facilitate cognitive offloading (i.e., grouped by color), whereas in the other condition they were arranged randomly. Across two experiments (total N = 166) the ordered condition improved task performance for children with low working memory ability. In addition, participants in Experiment 2 rated the difficulty of the two arrangements and performed a further condition in which they were given an opportunity to freely arrange the blocks before completing the task. Despite performing better in the ordered condition, children with low working memory ability did not rate the ordered arrangement as easier, nor did they choose an ordered arrangement when given the opportunity to do so. This research shows that cognitive offloading can also be a useful process in populations other than typical adults, and the implications of this work for supporting children with poor working memory are discussed.