工作记忆在归纳推理能力老化中的作用

目的：考查工作记忆系统中与目标保持密切相关的成分——工作记忆容量、转换和抑制功能在归纳推理能力老化中的作用。方法：招募年轻和老年被试共117名,接受图形推理测验、数字工作记忆广度测验、任务转换和Stroop测验。结果：工作记忆容量在归纳推理能力老化中起到显著的中介作用,而转换功能的中介作用则未达到显著。结论：增龄导致了工作记忆容量的衰退,进而造成了归纳推理能力的老化。     

工作记忆、加工速度和推理能力对小学儿童策略适应性的影响

研究选取89名小学三~五年级学生,探讨工作记忆、加工速度、推理能力以及年龄对小学儿童策略适应性的影响。通过路径分析发现:(1)工作记忆和推理能力对策略适应性有直接效应;工作记忆通过推理能力对策略适应性产生间接效应;加工速度通过"加工速度→工作记忆→策略适应性"和"加工速度→工作记忆→推理能力→策略适应性"两条路径对策略适应性起间接作用;在三个因素中,工作记忆对策略适应性的总效应最大,而推理能力对策略适应性的直接效应最大。(2)年龄对加工速度和推理能力有直接效应,但对工作记忆的效应不显著;年龄对策略适应性不产生直接效应,年龄通过"年龄→加工速度→工作记忆→策略适应性"、"年龄→加工速度→工作记忆→推理能力→策略适应性"和"年龄→推理能力→策略适应性"三条路径对策略适应性产生间接影响。     

加工速度、工作记忆与数字推理能力的发展

本研究得出在数字推理能力的发展过程中加工速度和工作记忆发挥着重要的作用,其中工作记忆对数字推理能力的发展的作用大于加工速度。加工速度可能是年龄与工作记忆的中介,加工速度可能仅对工作记忆的发展起一种直接调节作用,工作记忆对数字推理能力的发展可能起直接调节作用,在数字推理能力的发展过程中工作记忆比加工速度可能发挥着更直接、更一般的作用。     

工作记忆和感觉运动速度在心算加工年老化过程中的作用

对心算加工年老化研究有助于阐明认知老化规律,然而有关心算老化的少量研究结果仍存在不一致甚至矛盾之处。导致这种不一致的原因十分复杂,表面上看,不同认知老化研究所采用的统计方法不尽相同导致了结果的歧异。例如,在心算的年老化研究中,有的研究结论基于群体的数据分析,如层级回归分析(hierarchical regres-sion analyses)或方差分析,如Sahhouse和Coon(1994);另有一些研究先对每一个体数据作线性回归分析,如此得到斜率和截距(分别表示心算的中枢加工时间和外周感觉运动时间),然后再行层级回归分析或方差分析,如Al-len等(1992,1997)。这两类统计分析所得的结果很不一致。从理论上看,只要所采用的统计方法是合理的,统计方法的不尽相同应不会导致矛盾。但在实际情况下,统计分析误差增加了结论不一致的可能性,从而增大了揭示心算老化复杂性规律的难度。事实上,心算活动的年龄差异可能来自于记忆、加工速度等不同认知资源的老化差异。为了深入探讨这一问题,我们进一步研究了工作记忆和感觉运动速度在心算加工年老化过程中的作用。被试共161人,20—79岁,身体健康,受教育年限12年以上,以10岁段划分为6个年龄组,组间文化程度基本匹配。被试任务包括：(1)连续减法心算,分别为1000—3、1000—7、1000—13及1000—17等4种,在排除了被试看屏幕和按键的感觉运动时间后得到心算所需的时间;(2)数字计算工作记忆,根据工作记忆对信息同时进行加工和储存的特点,要求被试计算完题后再回忆答案,以获得工作记忆广度指标;(3)“数字复制”(digit copying),以获得感觉运动速度指标。实验在386微机上进行。对所得数据分别进行了上述群体数据与个体数据分析。两种数据分析方法得到了相同的结果,一致表明,在控制工作记忆与感觉运动速度的年龄差异后,心算活动的年龄差异显著降低。而且,控制感觉运动速度的年龄差异后心算活动年龄差异的降低程度要大于控制工作记忆的年龄差异后心算活动年龄差异的降低程度。这说明,感觉运动速度在心算加工年老化过程中发挥了更大作用。但是,工作记忆与感觉运动速度二者的年龄差异并不能完全解释心算活动的年龄差异,表明心算加工的年老化存在其特殊性过程,不支持认知老化的普遍减慢假说(genenalized slowing hypotllesis)。     

基本心理能力老化的中介变量

从整合思路,针对认知老化的四个中介变量建立基本心理能力老化的结构方程模型。样本来自北京三个社区的217位60-85岁的老人。采用计算机化的任务测查五项基本心理能力和加工资源的各项指标。结果表明：(1)感觉功能、加工速度和加工容量是基本心理能力老化的重要中介变量;(2)基本心理能力老化的中介作用表现出层次性。感觉功能是最基础的一层中介作用,它通过加工速度和加工容量间接调节基本心理能力的老化;加工速度对基本心理能力老化的作用受感觉功能的影响,同时也通过加工容量对基本心理能力的老化起作用;加工容量在基本心理能力老化的中介模型中直接与基本心理能力产生联系,但是其61％的变异来自感觉功能和加工速度;(3)负启动测验与颜色词启动测验不能共同表达加工抑制,以颜色词启动值作为观测指标的加工抑制不能进入基本心理能力老化的中介模型。     

基本心理能力老化的认知机制

基本心理能力老化机制是认知老化领域研究热点之一。横断研究与追踪研究表明, 感觉功能、加工速度、工作记忆等信息加工资源的衰退导致了基本心理能力的衰退。但由于相关研究不能进行因果推论, 基本心理能力老化的认知机制尚存在争论。因此本项目拟采用实验室研究和干预实验设计, 通过操纵感觉功能(知觉压力水平)、干预加工速度与工作记忆, 考察基本心理能力的年龄差异的变化, 以期为认知老化理论的深化和拓展提供实验依据。     

语文学习困难儿童的工作记忆与加工速度

加工速度和工作记忆反应了不同的认知加工过程,在认知发展研究中,加工速度和工作记忆所起的作用仍存在较大的分歧.采用多因素混合实验设计,在严格控制条件下,比较了语文学习困难和控制组儿童的工作记忆和加工速度.结果发现,与控制组相比,语文学习困难儿童在工作记忆和加工速度方面均存在明显的不足,但加工速度不能解释不同能力组之间的差异,语文学习困难儿童的缺陷在于工作记忆能力的下降.工作记忆的缺陷在于言语工作记忆和中央执行功能的不足,与视空间工作记忆能力无关.语文学习困难既存在一般的工作记忆缺陷(中央执行功能)也存在特定的工作记忆(言语工作记忆)能力的不足.     

一般流体智力的结构与老化机制--结构方程模型的比较

近年来一般流体智力的认知结构与老化机制已成为认知研究中的一个热点。本研究通过结构方程模型探讨了认知加工速度、工作记忆、注意能力与一般流体智力的联系,结果表明：加工速度、控制性注意是一般流体智力的主要认知成分,工作记忆并非一般流体智力的认知成分,两者之间足共变关系。加入年龄因子的结构方程模型也证实了加工速度和控制性注意是一般流体智力老化的重要中介因子。     

《基本认知能力测验》（2．0版）及其软件简介

基本认知能力是人脑高级智能活动的基础,对于完成复杂的认知活动起重要作用。中国科学院心理研究所李德明研究员课题组,在多年来关于认知功能年老化及毕生发展研究的基础上,自行设计和编制了这套《基本认知能力测验》(1．0单机版)及其软件,率先将近期理论研究成果——加工速度和工作记忆指标,     

加工速度和工作记忆在认知年老化过程中的作用

研究加工速度和工作记忆在认知能力年老化过程中的作用。被试为20-90岁的健康成人1350名,完成加工速度、工作记忆及一组认知能力测验,应用分层回归分析方法考查在年老化过程中加工速度和工作记忆对多项认知变量的作用量。结果表明,在年老化过程中,加工速度和工作记忆对认知变量的作用量分别约为87% 和76%;二者的综合作用量约为94%。说明加工速度和工作记忆在认知能力年老化过程中起决定作用     

The Executive Decline Hypothesis of Cognitive Aging: Do Executive Deficits Qualify as Differential Deficits and Do They Mediate Age-Related Memory Decline?

This paper reports the results of two studies which investigated whether aging is associated with a differential deficit in executive function, compared with deficits in general cognitive ability (Wechsler Adult Intelligence Scale-Revised performance). Further, the studies investigated the specificity of the executive decline hypothesis of memory and aging by examining whether declines in executive function mediate age-related memory decline over and above the variance in memory accounted for by general cognitive ability. The results of Study 1 showed no consistent evidence of a differential decline in executive function among a sample of participants aged between 18 and 75 years. The results of Study 2 indicated a differential decline in one indicator of executive function, the Modified Card Sorting Test, among an older sample aged between 60 and 89 years. Both studies demonstrated that measures of executive function accounted for age-related variance in free recall, recognition, and serial recall, even after controlling for general cognitive ability. However, in Study 1, once variance attributed to speed of processing was taken into account, executive function did not contribute further to the age-related variance.     

Mapping the developmental constraints on working memory span performance

This study investigated the constraints underlying developmental improvements in complex working memory span performance among 120 children of between 6 and 10 years of age. Independent measures of processing efficiency, storage capacity, rehearsal speed, and basic speed of processing were assessed to determine their contribution to age-related variance in complex span. Results showed that developmental improvements in complex span were driven by 2 age-related but separable factors: 1 associated with general speed of processing and 1 associated with storage ability. In addition, there was an age-related contribution shared between working memory, processing speed, and storage ability that was important for higher level cognition. These results pose a challenge for models of complex span performance that emphasize the importance of processing speed alone.     

Cognitive Mechanisms Underlying Decrements in Mental Synthesis in Older Adults

The extent and nature of age-related differences in mental synthesis was examined in light of Baddeley's working memory model and resource theories. Mental synthesis performance of 30 young, young-old, middle-old and old-old adults was examined using a dual-task experiment and individual differences approach. Age-related differences in mental synthesis were shown, with an unprecedented heightened decrement evident after the age of 85. The central executive was not a mechanism of this decline. Executive function, speed of information processing, and working memory capacity were mechanisms underlying this decline, and together accounted for 86% of the age-related variance in mental synthesis. Environmental support enhanced mental synthesis.     

教育水平对老年人认知能力的影响模式

来自北京三个社区的217位60~85岁的老年人接受了五项基本心理能力测验、感觉功能测查、加工速度和工作记忆容量的测试。运用相关分析、方差分析以及结构方程模型考察了教育水平对老年人基本心理能力的影响。研究得到：（1）从整体上看,教育水平对老年人基本心理能力的积极作用是普遍存在的,不依赖于具体的领域;分水平看,教育水平对认知功能的积极作用随教育水平的高低表现出领域间的差异。（2）教育水平与年龄各自独立地对老年人的认知能力产生影响,教育水平的作用是积极的,年龄的影响是极性的。（3）教育水平对老年人基本心理能力的影响不是直接的,而是以加工速度和工作记忆为中介的。     

Working memory, intelligence and reading ability in children

The dimensions of working memory in children and the relationships between working memory capacity, reasoning and reading ability were investigated. Simple and complex span tests were administered to 280 grade four, five and six elementary school children. Simple span tests were hypothesized to measure the capacity to temporary store information in working memory. Complex span tests were thought to reflect the simultaneous storage and processing of information. In addition, tests for reasoning, reading comprehension and reading speed were administered. Confirmatory factor analyses showed that the various tests for working memory formed one factor, which was interpreted as temporal storage capacity. The analyses revealed also that working memory and reasoning both were related to reading comprehension, but that these constructs differed in their relations to reading speed.     

Differences in mathematical reasoning between typically achieving and gifted children

Mathematical giftedness refers to mastery in a specific mathematical domain at an earlier than expected age. The present study examined which cognitive processes accounted for differences in mathematical reasoning between gifted children (MRG) and their typically achieving peers (TA). Naming speed, phonological awareness, short-term memory, executive functioning, and working memory were examined in 51 children aged approximately 7 years. A series of stepwise regression models, using a contrast variable to capture differences in mathematical reasoning between MRG and TA children, were created to examine which cognitive domains accounted for differences in mathematical reasoning. Short-term memory (r²?=?.08) and visual-spatial working memory (r²?=?.39) emerged as the only cognitive predictors within a model that included gender, age, and fluid intelligence. This model captured all of the variance distinguishing mathematics reasoning between MRG and TA children, explaining an overall contribution of 70% of the variance in mathematical reasoning.     

Using the process dissociation procedure to estimate recollection and familiarity in working memory: An experimental and individual differences investigation

Numerous studies have found that working memory capacity and perceptual speed predict variation in fluid intelligence. Within the cognitive ageing literature, perceptual speed accounts for substantial ageing variance in working memory capacity and fluid intelligence. However, within young adults, the interrelationships among these three abilities are less clear. The current work investigated these relationships via confirmatory factor analyses and structural equation modelling using tasks with verbal, spatial, and numerical content. The results indicate that working memory capacity and perceptual speed were not related in a large, cognitively diverse sample of young adults. However, both working memory capacity and perceptual speed accounted for unique variance in fluid intelligence. The results are discussed in relation to previous research with young and older adults.     

Cognitive Mediators of Age-Related Differences in Language Comprehension and Verbal Memory Performance

The present study tried to specify how much processing speed, working memory capacity, and inhibition capability contribute to the effects of aging on language performance. An individual-differences approach was used to examine the component processes that predict performance in language comprehension and verbal long-term memory tasks. A total of 151 participants aged 31-80 completed language processing tasks and a battery of tasks designed to assess processing speed, working memory, and resistance to interference. Latent-construct structural equation modeling was used to examine the relationships of these factors and age to different types of language tasks. The best fit model showed first that all the significant relationships between age and language performance are mediated through reductions in speed, resistance to interference, and working memory; this confirms the validity of the general factor approach of age-related differences in cognitive performance. The best fit model, however, also showed that the contribution of speed and resistance to interference is indirect and mediated by working memory, which appears to play a crucial role in explaining age-related differences in language performance.     

Storage and non-storage components of working memory predicting reasoning: A simultaneous examination of a wide range of ability factors

The current study examined basic cognitive abilities that are related to or included in the concept of working memory (WM): different WM components, three executive functions, simple short-term storage (STM), and sustained attention. Tasks were selected from well-established models and balanced in terms of content. The predictive power of storage and non-storage components of WM was examined. The same analyses were conducted with mental speed as an additional predictor of reasoning. Finally, we investigated whether the identified predictors of reasoning remain relevant when a general factor is considered in the analysis. The analyses revealed that short-term memory accounted for the relationship between complex span measures of WM and reasoning but not for the relationship between coordination and reasoning. These findings remained stable in the context of a mental speed and a general factor. The mental speed factor did not add an incremental contribution to the prediction of reasoning above and beyond short-term memory and coordination. The general factor was mainly built by mental speed tasks and acted as an additional predictor of reasoning besides STM and coordination. Thus, we concluded that reasoning ability can be explained by coordination, STM, and mental speed.