加工时间和加工速度对工作记忆广度的影响

对工作记忆广度机制的四个模型:资源共享模型、任务转换假说、干扰说和时间资源共享模型进行了检验。以60名大学本科生为被试,完成工作记忆广度任务和转换任务。结果表明:加工时间和加工项目数不是影响工作记忆广度的主要因素;工作记忆广度受到加工速度的影响;工作记忆广度和线索-任务转换代价呈显著的负相关关系。结果支持时间资源共享模型,工作记忆广度取决于注意在加工和存储之间快速、灵活的转换。     

工作记忆广度对语篇理解中重读效应的影响

本文探索了工作记忆容量对语篇理解中重读效应的影响。采用阅读广度测验对工作记忆容量进行测量, 筛选出高、低广度两组被试。并采用听觉动窗实验范式, 比较两组被试在语篇理解中即时加工时间的差异。研究结果表明, 重读效应受到工作记忆广度的显著影响。对于低工作记忆广度被试, 一致性重读促进语篇理解, 不一致性重读阻碍语篇理解; 但对于高工作记忆广度被试, 一致性重读的促进效应和不一致性重读的阻碍效应都不显著。另外, 只有在不一致性重读条件下, 低广度者语篇理解的即时加工时间显著多于高广度者, 而在一致性重读和无重读条件下则没有显著差异。最后用工作记忆的控制性注意理论对研究结果进行了讨论。     

顿悟问题解决不同阶段中工作记忆的作用

该研究探讨了顿悟问题解决不同阶段中工作记忆的作用。在实验1中,以87名大学生为被试,使用多种工作记忆广度任务和言语顿悟任务,探讨了工作记忆对于言语顿悟问题解决不同阶段的影响;在实验2中,以119名大学生为被试,使用多种工作记忆广度任务和空间顿悟任务,探讨了工作记忆对于空间顿悟问题解决不同阶段的影响。研究结果表明,初始搜索阶段与重构阶段是相对独立的两个阶段;工作记忆对于顿悟问题解决的不同阶段有着不同的影响,它主要影响顿悟问题解决的初始搜索阶段,工作记忆能力越强,初始搜索阶段所需时间越少;工作记忆对于顿悟问题解决的重构阶段无显著影响,这一点支持了关于重构内在机制的特殊过程观。     

信息加工效率与阅读的关系研究

对23名大学生进行知觉广度、记忆广度和阅读理解的多项测验,探求知觉、记忆加工效率与不同语言阅读成绩和阅读眼动特性之间的关系。结果发现：低水平的视觉符号方向信号知觉广度与阅读不存在明显的关系,从眼跳幅度指标上反映出右侧知觉广度大的被试对第二语言加工难度更为敏感。短时记忆和工作记忆能力对阅读的影响主要反映在眼跳幅度方面,与单个注视点获取的信息量有关,但与课文理解水平的关系不明显。短时记忆能力强的被试在眼跳幅度上以及第二语言言语工作记忆弱的被试在注视时间上均出现语言差异效应。     

工作记忆广度：资源限制、记忆消退还是转换机制？

为了检验工作记忆广度有限性的3种假说,即资源限制假说、记忆消退假说和转换机制假说,实验要求被试首先完成一项转换效率任务,然后完成工作记忆广度任务。结果发现,加工负荷对工作记忆广度具有重要影响,保持时间不影响工作记忆广度,转换效率与工作记忆广度也没有显著相关。实验结果支持工作记忆广度受认知资源限制的观点     

8岁到成年期工作记忆广度的发展

工作记忆与认知能力、智力和学习能力有密切的联系.本研究采用横断研究的方法,测量了213名8岁到成年期被试的数字、词语和视空间工作记忆广度,探查了工作记忆广度的发展情况.结果发现,数字工作记忆广度在此期间持续增长,词语广度在18岁达到最高,视空间工作记忆广度在14-16岁达到高峰.不同任务的工作记忆广度具有相似的发展趋势,但工作记忆的平均广度分数与Pascual-Leone模型的预测并不一致.     

6-9岁儿童工作记忆的发展研究

以Baddeley工作记忆模型为基础考察儿童语音环路、视觉空间模板、中央执行的发展及其与复杂广度的关系。225名6-9岁被试完成9个任务,分别测量听力广度及工作记忆三个子系统的功能。发现工作记忆各个子成分的功能在6-9岁期间发展速度不同;中央执行与语音环路和视觉空间模板的联系随年龄增长加强;结构方程模型分析发现中央执行和语音环路功能对儿童听力广度都有显著的直接影响,表明言语复杂广度任务既涉及中央执行功能也涉及语音环路的存贮功能。     

学科领域知识和学业成绩对工作记忆广度的影响

引入Alexander领域知识概念形成数学学科领域知识,以七年级有理数单元为研究材料,编写问卷和E-Prime实验程序,筛选60名初中生为被试,考察数学学科领域知识和学业成绩对工作记忆广度的影响。研究发现:(1)学优生的认知过程知识和问题条件知识显著高于学困生,而学理内容知识差异不显著;(2)在简单加工任务上,学优生和学困生工作记忆广度差异不显著。在复杂任务上,学优生的工作记忆广度都显著高于学困生;(3)当工作记忆广度任务中存储部分的词语和数学学科领域知识相关时,问题条件知识分数和认知过程分数能够显著地预测工作记忆广度。而不相关时,仅问题条件知识分数能够显著地预测工作记忆广度。     

阅读障碍与注意缺陷多动障碍儿童的语言加工和反应抑制

阅读障碍与注意缺陷多动障碍(ADHD)高度共病,以往研究结果显示两种障碍在语言加工、执行功能等领域的缺陷既相似又不同。本研究采用语音意识测验、快速命名测验、语素意识测验和停止信号任务,以及阅读广度测验,分别考察四组被试（阅读障碍组、ADHD组、双重障碍组、正常控制组）的基础语言加工、反应抑制和言语工作记忆能力,结果发现：阅读障碍组和双重障碍组在语言加工任务上的成绩均显著差于ADHD组和正常组;ADHD组和双重障碍组在停止信号任务上的成绩显著差于阅读障碍组和正常组;所有障碍组在阅读广度测验上的成绩显著差于正常组。表明阅读障碍的特异性缺陷体现在语言加工过程上,而注意缺陷多动障碍的特异性缺陷体现在反应抑制上。这对于今后单一障碍的研究及临床诊断和干预具有重要的参考价值。     

客体信息在视觉工作记忆编码和维持阶段的不同注意选择模式

视觉工作记忆不同加工阶段(编码、维持)对多特征客体信息的注意选择模式是否相同目前仍存在争议。本研究采用变化觉察范式,引入前注意线索和后注意线索,分别探测在视觉工作记忆编码和维持两个阶段中的注意选择模式。3个实验结果显示,在前注意线索试次中,被试对任务相关特征变化的觉察显著受到任务无关特征变化的干扰,表现为任务无关特征变化条件相比于不变条件的反应更慢,报告标准更低;且该干扰效应并不受记忆负荷的影响。而在后注意线索试次中,仅在低记忆负荷条件下(实验1a/1b)存在干扰效应,当记忆负荷增大后(实验2/3)干扰效应消失。结果表明,在视觉工作记忆编码阶段,客体中任务相关与无关特征均被编码进视觉工作记忆并相互竞争注意资源;而在维持阶段,任务无关特征仅在低记忆负荷条件下得到加工。结果揭示,在编码阶段的注意选择模式是基于客体的;而维持阶段的注意选择模式是基于特征的,且受到记忆负荷的调控。     

Individual Differences in Working Memory Capacity: More Evidence for a General Capacity Theory

The causes of the positive relationship between comprehension and measures of working memory capacity remain unclear. This study tests three hypotheses for the relationship by equating the difficulty, for 48 individual subjects, of processing demands in complex working memory tasks. Even with difficulty of processing equated, the relationship between number of words recalled in the working memory measure and comprehension remained high and significant. The results favour a general capacity view. We suggest that high working memory span subjects have more limited-capacity attentional resources available to them than low span subjects and that individual differences in working memory capacity will have implications for any task that requires controlled effortful processing.     

学习困难学生视空间工作记忆提取能力的多指标分析

本实验设计高、低两种加工负载的视空间WM作业,采用WM广度、提取错误值和提取速度三项指标评估学困生视空间WM的提取能力,比较学困生和学优生视空间WM的提取能力间的差异。结果表明：无论在低加工负载条件下还是在高加工负载条件下,学困生视空间WM的提取能力都比学优生差。在不同加工负载条件下,三项指标对评估学困生和学优生视空间WM提取能力间差异的重要程度不同。低加工负载条件下WM容量和提取错误值是较好的指标,而高加工负载条件下WM容量和提取速度是较好的指标。     

The structure of working memory abilities across the adult life span

The present study addresses three questions regarding age differences in working memory: (1) whether performance on complex span tasks decreases as a function of age at a faster rate than performance on simple span tasks; (2) whether spatial working memory decreases at a faster rate than verbal working memory; and (3) whether the structure of working memory abilities is different for different age groups. Adults, ages 20-89 (n = 388), performed three simple and three complex verbal span tasks and three simple and three complex spatial memory tasks. Performance on the spatial tasks decreased at faster rates as a function of age than performance on the verbal tasks, but within each domain, performance on complex and simple span tasks decreased at the same rates. Confirmatory factor analyses revealed that domain-differentiated models yielded better fits than models involving domain-general constructs, providing further evidence of the need to distinguish verbal and spatial working memory abilities. Regardless of which domain-differentiated model was examined, and despite the faster rates of decrease in the spatial domain, age group comparisons revealed that the factor structure of working memory abilities was highly similar in younger and older adults and showed no evidence of age-related dedifferentiation.     

Working memory and interference: A comment on Jenkins, Myerson, Hale, and Fry (1999)

Jenkins, Myerson, Hale, and Fry (1999) showed that slopes relating complex spans to simple spans were considerably smaller than one, indicating that persons with higher simple spans suffered more interference when the span task was combined with a processing demand. They argued that this finding ruled out accounts of working memory based on interference and/or inhibition of interfering information. We demonstrate that the effect is mainly an artifact from regression to the mean, owing to the low reliability of span scores as used by Jenkins et al. Data from 133 young adults for two verbal and two spatial span tasks show that the slopes relating complex to simple performance are considerably higher for sum scores than for span scores. Furthermore, an adequate test for an interference or an inhibition account of working memory is to predict interference from complex span tasks, not from simple span tasks. Interference effects in the verbal span tasks were negatively correlated with an independent measure of working memory capacity, consistent with the interference/inhibition account.     

Individual differences in sentence memory

Results from an experiment with two parts are presented in this paper. In part one, participants listened to sentences containing two, three, four, or five clauses, and were asked questions about the content of the sentences. The results of part one demonstrate that an important unit of representation in sentence memory is the clause, and not some other component of discourse structure. In part two, the same group of participants performed eight different short-term storage/working memory tasks. A composite complex span score was computed for each participant based on three working memory tasks closely based on Daneman & Carpenter's (1980) reading span task. This working memory measure was significantly correlated with the participants' performance on the sentence memory task in part one. A second working memory measure—N-back—was also significantly correlated with the participants' performance on the sentence memory task, and there was no correlation between their performance on the complex span task and the N-back task. It is therefore concluded that (i) working memory consists of a number of dissociable components; and (ii) memory for sentences taps into more than one of these working memory components. Furthermore, the high correlations of sentence memory with the complex span and the N-back tasks (neither of which are language processing tasks) suggests that memory for sentences is not simply a result of linguistic experience; rather, it is likely that an independent working memory component contributes to participants' performance on the sentence memory task.     

Examining the locus of age effects on complex span tasks

To investigate the locus of age effects on complex span tasks, the authors evaluated the contributions of working memory functions and processing speed. Age differences were found in measures of storage capacity, language processing speed, and lower level speed. Statistically controlling for each of these in hierarchical regressions substantially reduced, but did not eliminate, the complex span age effect. Accounting for lower level speed and storage, however, removed essentially the entire age effect, suggesting that both functions play important and independent roles. Additional evidence for the role of storage capacity was the absence of complex span age differences with span size calibrated to individual word span performance. Explanations for age differences based on inhibition and concurrent task performamce were not supported.     

The influence of complex working memory span task administration methods on prediction of higher level cognition and metacognitive control of response times

Participants between the ages of 18 and 80 were tested on a complex working memory span task that was administered either using a typical experimenter-paced method or using a method in which the processing component was presented at a fixed, limited-pace presentation rate. Path analyses revealed that even after controlling for individual differences in general processing speed, the limited-pace task predicted unique variance in episodic memory, executive functioning, and fluid intelligence, whereas the experimenter-paced task did not. For the experimenter-paced task, slower responses on the processing component of the task were associated with better recall, but only when individual differences in processing speed were controlled. These findings suggest that metacognitive control of response times affects recall from working memory span tasks, as well as the relationship between span task recall and high-level cognition. These results support resource-sharing explanations of working memory and suggest that limiting processing times using computer pacing of complex span tasks can be an effective way to efficiently measure working memory capacity.     

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.     

The Measurement of Verbal Working Memory Capacity and Its Relation to Reading Comprehension

Ninety-four subjects were tested on the Daneman and Carpenter (1980) reading span task, four versions of a related sentence span task in which reaction times and accuracy on sentence processing were measured along with sentence-final word recall, two number generation tasks designed to test working memory, digit span, and two shape-generation tasks designed to measure visual-spatial working memory. Forty-four subjects were retested on a subset of these measures at a 3-month interval. All subjects were tested on standard vocabulary and reading tests. Correlational analyses showed better internal consistency and test-retest reliability of the sentence span tasks than of the Daneman-Carpenter reading span task. Factor analysis showed no factor that could be related to a central verbal working memory; rotated factors suggested groupings of tests into factors that correspond to digitrelated tasks, spatial tasks, sentence processing in sentence span tasks, and recall in sentence span tasks. Correlational analyses and regression analyses showed that the sentence processing component of the sentence span tasks was the best predictor of performance on the reading test, with a small independent contribution of the recall component. The results suggest that sentence span tasks are unreliable unless measurements are made of both their sentence processing and recall components, and that the predictive value of these tasks for reading comprehension abilities lies in the overlap of operations rather than in limitations in verbal working memory that apply to both.     

How does the severity of a learning disability affect working memory performance?

Working memory performance was examined in children aged 11-12 years who had borderline, mild, and moderate learning disabilities. Comparisons with children of average abilities were used to determine whether those with more severe learning disabilities had greater impairments in working memory. Seven measures of working memory span were used to assess temporary phonological short-term storage (digit span, word span), temporary visuo-spatial short-term storage (pattern span, spatial span), and temporary short-term storage with additional processing, or central executive, demands (listening span. odd one out span, reverse digit span). Children with mild and moderate learning disabilities were impaired on all measures of working memory compared to children of average abilities. Children with borderline learning disabilities were just as good as children with average abilities on visuo-spatial and complex span tasks, but showed an impairment on phonological span tasks. Children with moderate learning disabilities were indistinguishable from children with mild learning disabilities on simple span tasks, but were significantly poorer than the mild group on the more demanding complex span tasks. For the group as a whole, working memory was strongly related to mental age.