认知老化对于老年人决策过程的影响:动机的调节作用

有关老化和决策制定的研究并没有发现一致的年龄差异。从决策过程的角度,论述了老化对于决策制定的多层面影响。从认知层面来讲,流体认知能力的衰减会使老年人在决策制定前搜索更少的信息,使用非补偿性策略,基于属性进行信息搜索和比较;晶体认知能力的相对保持则在一定情况下弥补了这种消极影响;从动机层面来讲,关注情绪管理目标的老年人会倾向于寻求更多积极的信息,为了避免权衡诱发的消极情绪而更多地使用非补偿性策略。动机对于认知老化的消极影响有调节作用。具体来说,社会情绪选择理论和选择性投入假设认为,当决策任务符合老年人的社会目标,即情绪管理目标时,能够激活老年人投入认知资源的动机,从而缓解认知资源的衰减对于老年人决策表现的消极影响。未来的研究需要通过实验设计进一步探索动机与认知的交互作用,将多种过程追踪技术结合起来,明晰动机和认知能力在老年人决策制定中的作用。另外考虑到在社会目标方面的年龄差异,对于老年人决策质量的衡量应该更加注重主观决策质量。     

情景记忆成功年老化的神经机制

随着年龄的增长, 大部分老年人的情景记忆会出现衰退, 但也会有一部分老年人的情景记忆表现出成功的年老化, 即记忆成绩较好或随增龄的衰退程度较小。脑保持理论、神经去分化理论、认知储备理论以及神经补偿理论分别从不同角度解释了情景记忆成功年老化的神经机制。基于选择性优化与补偿模型对现有理论进行整合, 发现情景记忆成功年老化可能与个体的认知储备水平直接相关：高认知储备的老年人能够对情景记忆相关的脑区和脑网络进行优化且具备更强的神经补偿能力, 因而其脑功能(比如, 神经表征和神经加工通路的特异性)可能会保持地更好。未来研究需要更多地采用纵向设计来考察各理论之间的关系及其影响因素, 从而更好地解释记忆成功年老化的神经机制并为提升老年人的脑与认知健康提供支持。     

语言产生中词频效应老化的神经基础与时间进程

词频效应指语言产生中人们对高频词汇的加工比低频词汇更快更准确的一种现象, 它可能发生在语言产生中的不同阶段。对青年人和老年人词频效应的不同特点和加工机制进行比较, 可以考察语言产生的认知老化机制。通过语言产生理论可对词频效应的老化进行预测, 提出词频效应在个体发展和老化阶段的相对稳定性, 分析老化导致词频效应相关的神经基础和加工时间进程的改变。未来研究可进一步分离词频效应与习得年龄效应对语言产生老化的影响, 并扩展至神经退行性疾病患者中。     

教育水平在认知老化中的作用

为考察教育水平在认知老化中的作用,分别使用横断数据和干预数据分析教育水平对认知老化的影响模式。对51名58～83岁的城市社区老年人实施加工速度测验和基本心理能力测验。随机选取25名被试作为干预组接受加工速度训练。被试在前测后第8周接受与前测内容相同的后测。横断分析的结果显示,在特定的认知测验中,教育水平对认知能力的年龄差异有调节作用。干预数据的分析结果显示,加工速度干预效果显著,且对词汇流畅性有迁移作用。但相关分析和回归分析的结果则表明,教育水平在促进老年人干预收益和迁移方面的作用不显著。在获取和应用新知识方面,教育水平的作用并不显著,其在认知老化中的作用可能更多地表现为对固有认知功能的保护。     

不同搜索情境下老化对自上而下注意加工的影响

在视觉搜索过程中,老年人是否可以在不同情境下调节自上而下和自下而上的加工水平尚不明确。为了探讨老化对认知灵活性的影响,研究采用空间线索范式,通过比较有效线索和无效线索来考察对线索的注意加工水平（注意捕获、注意抑制）,通过比较目标相关和目标无关线索的注意加工水平来考察自上而下和自下而上的作用,通过改变分心物一致性来调控不同的目标凸显情境。结果发现,年轻组在目标非凸显时的空间线索效应高于目标凸显时,表明年轻人会依据目标凸显性调整自上而下的加工水平;但老年组却没有产生这种差异,其更依赖自上而下的加工,注意系统会对目标相关的线索进行注意捕获,对目标无关的线索进行注意抑制。结果表明,随着年龄的增长,认知控制的灵活性下降,表现出对自上而下加工较多的依赖;此外,老年人依然保留着注意捕获和注意抑制的能力,这对认知老化中抑制能力受损的观点提出了挑战。     

基于N2pc成分的视觉空间注意功能老化机制

视觉空间注意是人的一种基本认知功能,对老年人的生活有重要影响。N2pc作为一种与注意选择相关的ERP成分,可以反映注意资源在空间上的分配,是研究视觉空间注意的一个良好指标。本文对此前基于N2pc成分的注意功能老化研究进行了综述。前人研究主要采用视觉搜索范式与空间线索范式。采用视觉搜索范式的研究发现,当目标周围有干扰子时,目标诱发的N2pc在老年人中振幅减小,潜伏期延迟,同时在行为上老年人与年轻人相比,正确率更低,反应时更长; 当目标周围无干扰子时,目标诱发的N2pc振幅老年人与年轻人相当或比年轻人更大,老年人的正确率与年轻人无显著差异。采用空间线索范式的研究发现,与目标无相同特征的线索奇异子(singleton cue)不会诱发N2pc,与目标有相同特征的线索奇异子诱发的N2pc未表现出年龄差异,差异体现在一种反映抑制的ERP成分—Pd上(年轻人有Pd而老年人没有),此时老年人在行为上表现出比年轻人更强的空间线索效应。这些研究共同说明,视觉空间注意功能的老化是一个复杂的过程,涉及到搜索目标时注意分配速度的减慢,对干扰子抑制能力的下降以及基于特征的注意捕获能力的良好保持。     

语义认知的习得、发展和老化及其神经机制

作为语言系统的重要组成部分, 探究语义认知发展机制及其神经机理对揭示人类语言发展、认知机制有着重要意义。以语义认知能力的习得、发展、老化认知机制为主线, 在系统阐释词汇-语义系统的习得、语义认知能力和策略发展的基础上, 进一步探讨了语义认知老化的认知机制及其神经机理。最后, 围绕儿童和成人的语义认知差异、句法和语义认知老化的差异、语义认知老化的影响因素等问题上进行了思考和展望。     

年老化与文本理解

年老化与文本理解的研究表明,老年人在表层形式和文本基础两个低水平表征上的理解和记忆能力下降,而在情境模型的建构和提取、更新等加工过程中都没有发现由于年老化引起的能力下降。在介绍这些研究的基础上,从情境模型与另两个低水平加工的不同特点和老年人自身的特殊性两个方面分析了老年人在不同层次表征水平加工能力差异的原因。对情境模型水平加工能力保持的潜在机制及相关的影响因素,以及如何弥补在低水平加工中认知能力因年龄而产生的下降等问题还需要进行探讨     

老化刻板印象研究现状及展望

老化刻板印象是人们对老年人所持有的观念与预期,它能显著影响老化刻板印象持有者的生理功能、认知功能和行为结果。现有研究主要集中在老化刻板印象的机制、影响因素和中介变量方面。研究发现,老化刻板印象是通过内化形成的,刻板印象威胁理论和自我刻板化是解释老化刻板印象的两种作用机制。认知加工过程中的抑制能力、情境和文化差异是影响老化刻板印象的主要因素,而老化自我知觉和刻板期望则是老化刻板印象影响效果变量的中介因素。未来研究除了要继续探讨意识水平、情境因素、个体特征对老化刻板印象的影响以及老化刻板印象对不同年龄群体影响的特点以外,还应关注中介和干预研究,并进一步加强跨文化研究。     

老年人认知老化及其多媒体学习设计

认知老化研究表明,老年人随着年龄的增长,其认知功能呈衰退趋势。但认知年老化过程的个体差异很大,有较大的变异性和可塑性。多媒体为学习者提供了新的具有重要潜在优势的学习环境,其在学习中的广泛应用使得越来越多老年学习者也面临着运用多媒体学习。文章试从认知老化研究出发,以认知负荷理论和多媒体学习认知理论为指导,探讨适合老年人认知特征的多媒体学习策略。     

Spatial navigation: Cognitive variables involved in route retracing among an elderly population

The cognitive processes involved in route retracing are not well known. This study aims to highlight them in an elderly population in which contradictory results have been obtained, certain studies showing specific difficulties for route retracing, others not. Thirty-nine elderly subjects performed a route-learning task (forward-backward) in a garden, then completed spatial knowledge tasks and standardised cognitive tests. Results show four factors that were predictive of route retracing performance: route repetition, the pointing task, and two standardised cognitive tests, one assessing spatial working memory, and another global cognitive efficiency. According to these results, route retracing involves route and survey knowledge (i.e., egocentric and allocentric strategy), and the integration of forward-backward perspectives is underpinned by the spatial working memory. Moreover, the subjects did not make more errors in route retracing than in the route repetition task, suggesting that a real environment could compensate for a failing allocentric strategy.     

Neural evidence supports a novel framework for spatial navigation

The spatial knowledge used for human navigation has traditionally been separated into three categories: landmark, route, and survey knowledge. While behavioral research has retained this framework, it has become increasingly clear from recent neuroimaging studies that such a classification system is not adequate for understanding the brain. This review proposes a new framework, with a taxonomy based on the cognitive processes and subprocesses involved in spatial navigation. The neural correlates of spatial memory can inform our understanding of the cognitive processes involved in human navigation, and conversely, the specific task demands of an experiment can inform the interpretation of neuroimaging results. This review examines the neural correlates of each cognitive process separately, to provide a closer inspection of each component of spatial navigation. While landmark, route, and survey knowledge are still important components of human navigation, the neural correlates are not neatly ascribed to these three categories. The present findings provide motivation for a more detailed examination of the cognitive processes engaged during wayfinding.     

Active and passive contributions to spatial learning

It seems intuitively obvious that active exploration of a new environment will lead to better spatial learning than will passive exposure. However, the literature on this issue is decidedly mixed—in part, because the concept itself is not well defined. We identify five potential components of active spatial learning and review the evidence regarding their role in the acquisition of landmark, route, and survey knowledge. We find that (1) idiothetic information in walking contributes to metric survey knowledge, (2) there is little evidence as yet that decision making during exploration contributes to route or survey knowledge, (3) attention to place–action associations and relevant spatial relations contributes to route and survey knowledge, although landmarks and boundaries appear to be learned without effort, (4) route and survey information are differentially encoded in subunits of working memory, and (5) there is preliminary evidence that mental manipulation of such properties facilitates spatial learning. Idiothetic information appears to be necessary to reveal the influence of attention and, possibly, decision making in survey learning, which may explain the mixed results in desktop virtual reality. Thus, there is indeed an active advantage in spatial learning, which manifests itself in the task-dependent acquisition of route and survey knowledge.     

信息呈现方式与学习者的个性特征对多媒体环境下学习效果的影响

采用两个实验:实验一以陈述性知识为学习内容,实验二以程序性知识为学习内容,在这两种情况下,分别用组间设计探讨信息呈现方式对不同认知风格和空间能力的学习者在多媒体环境下学习效果的影响。结果表明:(1)认知风格对陈述性知识在多媒体环境下的学习效果产生影响,而选择的多媒体信息呈现方式和被试的空间能力则对其不产生影响;(2)对于程序性知识的保持,多媒体信息呈现方式和被试认知风格都会对学习效果产生影响,被试空间能力则不会产生影响,而且被试不同的认知风格在不同的多媒体信息呈现方式上会产生不同的影响;(3)对程序性知识的迁移,多媒体信息呈现方式、被试认知风格和空间能力都会对多媒体环境下的学习效果产生影响,而且被试不同的认知风格和空间能力在不同的多媒体信息呈现方式上都会产生不同的影响。     

Bidirectional interactions between circadian entrainment and cognitive performance

Circadian rhythms influence a variety of physiological and behavioral processes; however, little is known about how circadian rhythms interact with the organisms' ability to acquire and retain information about their environment. These experiments tested whether rats trained outside their endogenous active period demonstrate the same rate of acquisition, daily performance, and remote memory ability as their nocturnally trained counterparts in tasks of sustained attention and spatial memory. Furthermore, we explored how daily task training influenced circadian patterns of activity. We found that rats demonstrate better acquisition and performance on an operant task requiring attentional effort when trained during the dark-phase. Time of day did not affect acquisition or performance on the Morris water maze; however, when animals were retested 2 wk after their last day of training, they showed better remote memory if training originally occurred during the dark-phase. Finally, attentional, but not spatial, task performance during the light-phase promotes a shift toward diurnality and the synchronization of activity to the time of daily training; this shift was most robust when the demands on the cognitive control of attention were highest. Our findings support a theory of bidirectional interactions between cognitive performance and circadian processes and are consistent with the view that the circadian abnormalities associated with shift-work, aging, and neuropsychiatric illnesses may contribute to the deleterious effects on cognition often present in these populations. Furthermore, these findings suggest that time of day should be an important consideration for a variety of cognitive tasks principally used in psychological and neuroscience research.     

The influence of intentional and incidental learning on acquiring spatial knowledge during navigation

In order to study the influence of intentional and incidental learning conditions on route learning, young adults walked a route through a university building. Half of the participants focused their attention on the route (intentional learning condition), while the other half did not (incidental learning condition). Five tests of spatial knowledge were employed: a route-length-estimation, landmark recognition, landmark ordering, map-drawing and navigation task. The intentional group performed better than the incidental group on the map-drawing and navigation task. No difference between the intentional and incidental group was found on the landmark-recognition and landmark-ordering task. Moreover, the intentional group overestimated the walking distance, while the incidental group underestimated it. These results suggest that route knowledge (landmark recognition and landmark ordering) requires less effortful processing than survey knowledge (developing a map-like representation and actual navigation).     

Age changes in processing speed as a leading indicator of cognitive aging

Bivariate dual change score models were applied to longitudinal data from the Swedish Adoption/Twin Study of Aging to compare the dynamic predictions of 2-component theories of intelligence and the processing speed theory of cognitive aging. Data from up to 5 measurement occasions covering a 16-year period were available from 806 participants ranging in age from 50 to 88 years at the first measurement wave. Factors were generated to tap 4 general cognitive domains: verbal ability, spatial ability, memory, and processing speed. Model fitting indicated no dynamic relationship between verbal and spatial factors, providing no support for the hypothesis that age changes in fluid abilities drive age changes in crystallized abilities. The results suggest that, as predicted by the processing speed theory of cognitive aging, processing speed is a leading indicator of age changes in memory and spatial ability, but not verbal ability.     

老年期语义理解能力与空间定向能力的交叉滞后分析

来自北京三个社区的144位60~85岁的老年人参加了间隔时间为20个月的词语解释和心理旋转前后测测查,以考察语义理解能力在空间定向能力老化中的作用。运用重复测量方差分析、交叉滞后回归分析考察了两个变量上老年人在20个月期间发生的变化,以及两个变量间的因果关系。结果发现：(1)各年龄组老年人的语义理解能力均有下降,空间定向能力均有提高。(2)前测语义理解能力可预测后测空间定向能力。(3)不同语义理解能力水平的被试空间定向能力在前后测中的提高是相同的。     

How do we get there? Effects of cognitive aging on route memory

Research into the effects of cognitive aging on route navigation usually focuses on differences in learning performance. In contrast, we investigated age-related differences in route knowledge after successful route learning. One young and two groups of older adults categorized using different cut-off scores on the Montreal Cognitive Assessment (MoCA), were trained until they could correctly recall short routes. During the test phase, they were asked to recall the sequence in which landmarks were encountered (Landmark Sequence Task), the sequence of turns (Direction Sequence Task), the direction of turn at each landmark (Landmark Direction Task), and to identify the learned routes from a map perspective (Perspective Taking Task). Comparing the young participant group with the older group that scored high on the MoCA, we found effects of typical aging in learning performance and in the Direction Sequence Task. Comparing the two older groups, we found effects of early signs of atypical aging in the Landmark Direction and the Perspective Taking Tasks. We found no differences between groups in the Landmark Sequence Task. Given that participants were able to recall routes after training, these results suggest that typical and early signs of atypical aging result in differential memory deficits for aspects of route knowledge.