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。     

基于事件的前瞻记忆与认知控制

前瞻记忆和认知控制是人类认知能力的重要组成部分。Bugg等人(2013)发现前瞻记忆多重加工模型和双重认知控制理论具有共性。此后,越来越多的研究者关注认知控制在意图执行中和执行完成后的作用。本文对近年来关于前瞻记忆与认知控制的研究进行了梳理,发现认知控制对前瞻记忆的完成起支持作用,但二者也在脑机制层面存在差异。本研究能为未来更深入地探讨前瞻记忆的加工机制及生理基础提供新的视角。     

时间性前瞻记忆的影响因素及机制

时间性前瞻记忆是指个体记得在未来的某一时间或间隔一段时间以后做某事。与事件性前瞻记忆相比, 时间性前瞻记忆需要更多自我启动的注意资源, 并主要受到任务重要性、年龄、进行中任务的性质、时间间隔等因素的影响。时间性前瞻记忆主要与额叶有关, 对于其内部认知机制解释的理论模型主要有测试-等待-测试-退出模型以及注意阀门模型。但是时间性前瞻记忆的影响因素以及机制, 尤其是神经机制方面尚需要进一步的研究。     

注意状态、认知方式与前瞻记忆的TAP效应

采用经典实验室研究范式,实验一探讨了前瞻记忆任务为知觉加工条件下,注意状态和前瞻记忆任务与进行中任务一致和不一致时对不同认知方式个体前瞻记忆成绩的影响,实验二探讨了前瞻记忆任务为语义加工条件下,注意状态和前瞻记忆任务与进行中任务一致和不一致时对不同认知方式个体前瞻记忆成绩的影响,结果表明,（1）在前瞻记忆任务加工类型是语义加工和知觉加工两种条件下,场依存与场独立个体均发现了TAP效应的存在,而且场依存个体表现出更明显的TAP效应;（2）当前瞻记忆任务与进行中任务的加工类型不一致时,场独立个体的前瞻记忆成绩明显高于场依存个体,而在两类任务加工类型一致情况下,场独立与场依存个体的前瞻记忆成绩不存在明显差异;（3）在前瞻记忆任务是知觉加工时,分心对前瞻记忆成绩有明显不利的影响;而在前瞻记忆任务是语义加工时,只有当前瞻记忆任务与进行中任务加工类型不一致时,分心对前瞻记忆才有明显不利的影响,而且在分心条件下的TAP效应更明显。     

事件性前瞻记忆的加工机制：来自ERP的证据

采用事件相关电位技术,对前瞻记忆的加工机制——主要是执行前的加工机制进行研究。控制条件为单纯的背景任务,实验条件为背景任务含前瞻记忆任务,对两种条件下非靶线索的行为数据进行比较,结果表明实验条件下被试的反应时显著长于控制条件,可能说明两种条件的认知过程存在差异,这种差异在ERPs上主要体现为刺激呈现200ms以后,两种条件的波形和脑地形图存在显著差异。结果支持预备注意加工和记忆加工理论,也部分支持多重加工理论     

前瞻记忆意向后效应的年龄差异

前瞻记忆意向后效应会对日常生活产生负面影响,研究发现这种现象在老年人中尤其突出。近些年来,研究者们从内外两方面对影响前瞻记忆意向后效应年龄差异的因素进行了探讨,了解到认知老化所带来的抑制能力的衰退以及短时记忆缺陷是造成其年龄差异的主要原因。未来研究需进一步拓展对认知老化的机制和抑制控制能力的认识。另外,可以采用事件相关电位（Event-Related Potentials, ERPs）和功能性磁共振成像（Functional Magnetic Resonance Imaging, fMRI）等脑成像技术揭示前瞻记忆意向后效应年龄差异的加工机制及神经机制。     

前瞻记忆意向后效应的年龄差异

前瞻记忆意向后效应会对日常生活产生负面影响,研究发现这种现象在老年人中尤其突出。近些年来,研究者们从内外两方面对影响前瞻记忆意向后效应年龄差异的因素进行了探讨,了解到认知老化所带来的抑制能力的衰退以及短时记忆缺陷是造成其年龄差异的主要原因。未来研究需进一步拓展对认知老化的机制和抑制控制能力的认识。另外,可以采用事件相关电位（Event-Related Potentials, ERPs）和功能性磁共振成像（Functional Magnetic Resonance Imaging, fMRI）等脑成像技术揭示前瞻记忆意向后效应年龄差异的加工机制及神经机制。     

前瞻记忆意图后效中执行错误的机制

前瞻记忆意图后效是指已完成或取消的意图失活失败对当前认知任务造成的干扰。近期研究采用前瞻记忆任务范式探究意图后效的影响因素及认知机制。自发提取-抑制失败和预备性监控两种认知机制的分歧在于提取旧意图是否依赖注意资源的参与。脑成像研究也证实意图提取存在两条神经通路：自发提取通路和预备性监控提取通路。未来研究应探索兼容有意遗忘失败、旧意图再提取、抑制失败三者的研究范式以及降低执行错误的有效措施。     

加工焦点性和任务负荷对不同认知方式大学生前瞻记忆的影响

采用双任务范式,探讨了加工焦点性和进行中任务负荷对不同认知方式大学生前瞻记忆的影响。包括两个实验:实验一探讨进行中任务与前瞻记忆任务加工的焦点性和加工类型的一致性对不同认知方式大学生前瞻记忆的影响;实验二探讨进行中任务负荷对不同认知方式大学生在在焦点加工和非焦点加工条件下前瞻记忆的影响。结果显示:焦点加工条件下的前瞻记忆成绩高于非焦点加工,且不受进行中任务负荷的影响;不管进行中任务与前瞻记忆任务的加工类型是否一致,在进行中任务负荷较高且非焦点加工条件下,场独立大学生的前瞻记忆成绩高于场依存大学生。本研究结果支持多重加工理论。     

自然物体分类的ERP研究

对事物进行分类的能力是人类的一种基本认知功能。该文主要就近年来自然物体分类的事件相关电位（ERP）研究情况进行综述。首先介绍与自然物体分类有关的ERP早晚期成分;接着讨论了快速视觉分类的加工机制,认为前馈机制在这种复杂分类任务的视觉加工过程中起重要作用;最后详细介绍了两个分离的视觉加工机制,认为自然物体的视觉分类在不同时程涉及不同机制：即首先是任务无关的早期知觉加工过程,其次是任务相关的、类别无关的加工机制,与被试的决策有关。也讨论了这两个分离的加工过程涉及的神经基础。     

Human recognition memory: a cognitive neuroscience perspective

For many years the cognitive processes underlying recognition memory have been the subject of considerable interest in experimental psychology. To account for a broad range of behavioral findings, psychologists have put forward a variety of 'dual-process' models, all of which propose that recognition memory is supported by two forms of memory - familiarity and recollection - that differ in their speed of operation and the specificity of the retrieved information. More recently, the dual-process framework has been extended to encompass findings from studies investigating the neural basis of recognition memory. Results from neuropsychological, ERP and functional neuroimaging studies can be accommodated within the framework, and suggest that familiarity and recollection are supported by distinct neural mechanisms.     

Syntactic working memory and the establishment of filler-gap dependencies: insights from ERPs and fMRI

In this contribution, we review an ERP experiment and an fMRI experiment which investigated the processing of German wh-questions. On the basis of the ERP results, we will discuss current models of sentence processing and resource distribution during sentence comprehension. We argue that there exists a separate cognitive or neural resource that supports syntactic working memory processes necessary for the temporary maintenance of syntactic information for the parser. In the context of wh-movement, such a memory component is necessary for establishing filler-gap dependencies. The data obtained from the fMRI experiment will be used to discuss the results of previous neuroimaging studies of sentence processing. It is claimed that syntactic working memory, rather than syntactic processing per se, is supported by Broca's Area.     

Interrupted actions affect output monitoring and event-related potentials (ERPs)

Memory for performed and interrupted actions was measured on source recognition and source recall tests in order to investigate output monitoring (i.e., memory for actions). Event-related potentials (ERPs) were recorded during the source recognition test to provide insight into the neural basis of output monitoring (OM). Source identification and recall of performed actions was greater than interrupted actions, thereby replicating the enactment effect. Examination of memory errors revealed that interrupted actions were more often mistaken as performed actions. The ERP data indicated that brain activity elicited by performed actions differed from interrupted and new actions. A clear difference in temporal onset of two ERP effects (i.e., a central-parietal and a frontal ERP difference) was observed, and it supports the previous hypothesis that two distinct processes support OM and source monitoring judgements. The pattern of frontal ERP differences suggested that interrupted actions prompted people to use more systematic decision processes overall to make OM judgements. Central-parietal ERP effects suggested that sensori-motor information was not recollected for interrupted actions--rather OM judgements were based on cognitive operations in this case.     

Developmental changes in memory encoding: insights from event‐related potentials

The aim of the present study was to investigate developmental changes in encoding processes between 6‐year‐old children and adults using event‐related potentials (ERPs). Although episodic memory (‘EM’) effects have been reported in both children and adults at retrieval and subsequent memory effects have been established in adults, no previous ERP studies have examined subsequent memory effects in children. This represents a critical gap in the literature because encoding processes, and changes in neural correlates supporting encoding, partially account for age‐related improvements in children's memory performance. Results revealed that subsequent memory effects differed between children and adults temporally, directionally, and topographically. These findings lend support to the hypothesis that encoding processes and their neural correlates are an important source of change in memory development. A video abstract of this article can be viewed at http://youtu.be/sH83_qVimgc .     

记忆机制中再认的事件相关电位

ERP对于记忆的研究有独到之处,在研究方法是有外显的直接范式和内隐的间接范式,分别表现为ERP新旧效应和重复效应,即在刺激200ms以后的正向偏移.对于记忆提取的ERP效应已有一些理论解释,但在听觉记忆、汉字记忆以及记忆的脑内机制等方面还需要进一步的深入研究.     

Interrupted actions affect output monitoring and event-related potentials (ERPs)

Memory for performed and interrupted actions was measured on source recognition and source recall tests in order to investigate output monitoring (i.e., memory for actions). Event-related potentials (ERPs) were recorded during the source recognition test to provide insight into the neural basis of output monitoring (OM). Source identification and recall of performed actions was greater than interrupted actions, thereby replicating the enactment effect. Examination of memory errors revealed that interrupted actions were more often mistaken as performed actions. The ERP data indicated that brain activity elicited by performed actions differed from interrupted and new actions. A clear difference in temporal onset of two ERP effects (i.e., a central-parietal and a frontal ERP difference) was observed, and it supports the previous hypothesis that two distinct processes support OM and source monitoring judgements. The pattern of frontal ERP differences suggested that interrupted actions prompted people to use more systematic decision processes overall to make OM judgements. Central-parietal ERP effects suggested that sensori-motor information was not recollected for interrupted actions—rather OM judgements were based on cognitive operations in this case.     

基于Think/No-think范式的动机性遗忘研究:行为与脑机制

想/不想范式(Think/No-think,TNT)是基于go/no-go范式提出来的用于研究动机性遗忘过程的实验范式,主要过程是指个体对于记忆的提取抑制可以导致随后该记忆的遗忘。近年来TNT范式的大量行为学研究都一致性地发现记忆提取抑制可以产生负性控制效应,验证了在实验室情境下对动机性遗忘进行研究的可行性。其中,负性控制效应指的是压抑条件的项目相对于基线条件的项目的回忆量有显著降低。关于动机性遗忘发生的神经机制的探讨已积累了大量的研究证据,总结脑电(EEG)和功能核磁共振(f MRI)两个模态的研究,我们提出了动机性遗忘发生的多模态功能网络模型。最后,在该模型的基础上,我们展望了TNT范式未来的研究方向,其中特别注意到同步EEG-f MRI技术的应用有望为我们揭示出记忆提取抑制导致的动机性遗忘发生的动态过程。     

Electrophysiological correlates of processes supporting memory for faces

The retrieval processes supporting recognition memory for faces were investigated using event-related potentials (ERPs). The focus for analyses was ERP old/new effects, which are the differences between neural activities associated with correct judgments to old (studied) and new (unstudied) test stimuli. In two experiments it was possible to identify three old/new effects that behaved as neural indices of the process of recollection. In both experiments there was one old/new effect that behaved as an index of the process of familiarity. These outcomes are relevant to the ongoing debate about the functional significance of ERP old/new effects and the implications that scalp-recorded electrophysiological data have for theories of the processes supporting long-term memory judgments.     

Frontal deficits in alcoholism: an ERP study

Alcoholism is a major health problem afflicting people all over the world. Understanding the neural substrates of this addictive disorder may provide the basis for effective interventions. So-called "executive processes" play a role in cognitive functions like attention and working memory, and appear to be disrupted in alcoholism (Noel et al., 2001). Event related potentials (ERPs) provide an excellent, minimally invasive technique for exploring these neural deficits. The current study used the P300 in number sequencing task (modified version of the Petries & Milner, 1982) requiring working memory to compare a group of patients with alcoholism and frontal lobe lesions to patients with subcortical lesions and normal controls to assess the relationship of alcoholism to frontal lobe damage. The ERP paradigm was a Number Sequencing task. Electrophysiological results indicate that the frontal lesion group had significant P300 amplitude reduction and a similar trend for alcohol dependent group but not the subcortical group compared to the normal controls.