工作记忆容量和加工速度在归纳推理能力老化中的作用

利用结构方程模型考察了工作记忆容量和加工速度在归纳推理老化中的作用。样本为217名社区老人。结果发现：(1)工作记忆容量在归纳推理老化中具有重要作用．语音环路和视空问初步加工系统在推理过程巾参与程度相当。(2)在年龄和归纳推理能力之问存在年龄——加工速度——工作记忆容量——归纳推理这样一条层级关系。年龄、加工速度和工作记忆容量共同解释归纳推理中57％的变异。     

工作记忆对时间加工的影响

非时间信息加工与时间加工的关系是复杂的, 存在双向干扰或单向干扰, 结果的不一致与任务所需的注意资源及工作记忆都有关。工作记忆的中央执行系统在时间加工中起主要作用, 同时进行的非时间任务对中央执行功能的需求越多, 两种任务之间的干扰程度越大。语言环和视空间模板对时间加工的影响与非时间信息的类型有关。工作记忆作为一个整体以工作记忆容量为指标, 计时成绩也表现出与工作记忆容量有关的年龄、智力等方面的差异。时间加工和工作记忆在额叶、顶叶、基底神经节等皮质存在共同的神经机制。未来应该丰富工作记忆的研究内容, 结合时间加工的分段性探讨工作记忆影响时间加工的具体进程及神经机制, 并力求在应用方面取得一定的成果。     

振动触觉频率信息的工作记忆容量及存储机制

工作记忆可以同时保存多个信息并且容量有限, 这一内在机制是工作记忆研究的重点问题。视觉和言语等研究领域都发现工作记忆能够存储多个信息单元, 但对振动触觉工作记忆是否能存储多个频率信息目前尚无相关研究。由于振动触觉频率刺激和视觉刺激具有不同的神经编码机制, 以及振动频率信息是通过躯体感觉产生的模拟的、单维的、参数化信息, 振动触觉工作记忆容量及其加工存储机制的研究也必不可少。首先, 本项目将采用新的实验范式, 探究不同的刺激呈现方式以及不同反应报告方式下, 振动触觉工作记忆的容量及其认知机制。其次, 本项目也将同时运用功能磁共振成像(fMRI)技术, 来阐述振动触觉工作记忆加工存储的神经机制。探究基于触觉频率信息的参数工作记忆容量及其神经机制是完善工作记忆模型的重要补充, 将有助于提高我们对工作记忆系统的理解, 并为视觉、听觉、触觉多模态感知觉信息的跨通道研究奠定基础。     

工作记忆容量的差异对第二语言句法歧义句加工的影响

采用眼动技术, 以句子阅读过程中, 句子不同区段的首次注视时间作为句子即时性加工的指标, 回扫次数和总的注视时间作为句子非即时加工的指标, 考察了非熟练的汉-英双语者, 工作记忆容量的差异对第二语言(英语)暂时句法歧义句加工的影响。结果显示: 高工作记忆容量的被试, 在句子不同区段的首次注视时间和总的注视时间均短于低工作记忆容量的被试; 高、低工作记忆容量被试的回扫模式相似。研究结果表明, 对于非熟练的汉-英双语者, 工作记忆容量的差异既影响英语句法歧义句即时性的加工, 也影响非即时性的加工, 即工作记忆容量的差异既影响英语句法歧义句初始的句法加工过程, 也影响句法的重新分析过程。研究结果在一定程度上支持工作记忆容量限制的理论。     

1～6秒时距认知分段性特征

时距认知分段性指不同长度时距的加工机制和表征方式是不同的。以往研究者对1 s以上时距认知的分段性仍存在分歧,为了探讨这一主题,本研究设计了实验1和实验2。实验1采用时间复制任务比较高、低工作记忆容量被试在完成1~6 s视、听时距加工的成绩,结果发现,时距长度与工作记忆容量或通道均存在交互作用,被试在复制1 s、2 s的平均复制时距、复制比率及变异系数没有随工作记忆容量或通道而变化,而复制3 s、4 s、5 s及6 s时,高WMC组较低WMC组或听觉组较视觉组,平均复制时距显著更长、复制比率显著更高、变异系数显著更小。实验2采用时间产生任务比较高、低工作记忆容量被试在完成1~6 s视、听时距加工的成绩,结果也发现,时距长度与工作记忆容量或通道均存在交互作用,被试在产生1 s、2 s的平均产生时距、产生比率及变异系数没有随工作记忆容量或通道而变化,而产生3 s、4 s、5 s及6 s时,高WMC组较低WMC组或听觉组较视觉组,平均产生时距显著更短、产生比率显著更低、变异系数显著更小。这意味着1~6 s的时距认知存在分段性,大约2~3 s可能为分段临界点。时间认知的分段性可以用时间工作记忆说解释,该假说是时间认知分段综合模型解释短时距加工分段性的具体表现形式。     

信息保持、短时存贮与执行控制的脑模型

工作记忆的脑机制是认知神经科学研究的重要问题。研究者在分析大量脑成像研究数据的基础上,创建了许多解释工作记忆神经基础的模型。Smith和Jonides发展了工作记忆成分结构模型和贮存与执行加工分离模型。Postle和D’Esposito建构了工作记忆相对表征混合模型,D’Esposito, Postle和Rypma阐述了工作记忆加工阶段动态模型。Fletcher和Henson提出工作记忆额叶分区整合理论。该文通过对上述模型或理论的评价,总结了工作记忆脑成像研究中存在的问题,展望了该研究领域的发展趋势。     

工作记忆容量研究新进展

工作记忆容量作为直接影响人类完成高级认知活动的重要因素而倍受心理学家的关注.长期以来关于工作记忆容量的研究主要集中于工作记忆的执行性控制成分与高级认知活动的关系上,忽略了对注意焦点的研究,而注意焦点则是为了进行当前的认知加工而把从记忆的激活部分提取出来的信息组块加以保持的一个容量有限系统.该文作者讨论了关于工作记忆中注意焦点容量的研究及认识,并指出了当前研究中存在的问题.     

PTSD易感性人格特质、工作记忆能力和创伤期间认知加工对模拟创伤闪回的影响

基于模拟创伤研究范式, 采用道路交通事故影片对159名健康大学生进行模拟创伤, 考察PTSD易感性人格特质(特质焦虑、特质分离和神经质)、工作记忆能力(注意控制和工作记忆容量)和创伤期间认知加工(数据驱动加工和概念加工)对模拟创伤后不同时段闪回的影响。运用结构方程模型分析数据, 结果发现：(1)数据驱动加工正向预测不同时段闪回(即时闪回、一周闪回和触发闪回)的数量、生动性、痛苦度以及一周侵入频率; (2)神经质正向预测触发闪回痛苦度, 注意控制和工作记忆容量负向预测一周侵入频率; (3)概念加工在注意控制与即时闪回痛苦度之间起中介作用。研究结果提示：数据驱动加工是创伤后不同时段闪回的主要影响因素; 概念加工主要作用于早期急性应激反应, 注意控制是其保护因素; 神经质和工作记忆能力对闪回具有较长期的影响, 且工作记忆能力具有一定的保护作用。     

由两个模型看视觉工作记忆容量机制的研究

在众多的实验基础上, 研究者提出了分析视觉工作记忆的“容量有限模型”和“资源灵活分配模型”, 而两个模型在以下三方面存在着争论：(1)视觉工作记忆中保存的项目精度是否是固定的, (2)资源分配的模式是连续分配的还是以量子化模式分配的, (3)存储单元是以特征为单元还是以客体为单元。未来该领域的研究应加强对视觉工作记忆容量单元的探讨, 探索应用新的研究方法, 控制影响视觉工作记忆容量的空间因素等。     

文本阅读中预期推理生成的容量制约性

本研究通过操纵读者信息加工的时间量考察了工作记忆容量对预期推理生成的影响性质。结果表明,如果没有信息加工时间的限制,则工作记忆容量低的读者也能表现出在阅读中生成预期推理的证据,而如果读者的阅读加工时间受一定限制,则工作记忆容量低者建构预期推理的证据随着被允许的加工时间的缩短而逐渐消失。结果支持“工作记忆容量只影响阅读中预期推理建构速度”的观点。     

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。     

工作记忆中的注意焦点转换

在工作记忆中的选择性注意及注意焦点机制的基础上,从3个方面回顾了对工作记忆中注意焦点转换的研究：（1）工作记忆中的注意焦点转换的概念及其基本研究方法;（2）影响注意焦点转换代价的因素,包括提取、复述、加工、更新和记忆集大小等;（3）注意焦点转换与工作记忆各功能成分之间的关系,包括注意焦点转换与工作记忆执行功能的关系,注意焦点转换反映的存储、加工和执行功能之间的相互关系,注意焦点转换与工作记忆中资源分配的关系。最后,该文展望了未来的研究方向     

儿童类比推理的影响因素及干预促进

类比推理这一重要认知能力能够帮助儿童在未经历过的复杂情况下进行推断和学习。近年来研究者主要从行为研究、计算机模型和眼动技术的角度探究了儿童抑制控制和工作记忆在类比推理中的交互作用模式及类比推理策略对类比推理的影响。在此基础上,研究者围绕语言标签和物理表征两方面对儿童类比推理进行了干预研究。儿童类比推理的未来研究应着眼于改进研究方法、关注类比推理各加工阶段影响因素及加强儿童类比推理策略的干预应用研究。     

工作记忆新探:基于个体差异的研究

近年来对工作记忆的研究开始关注个体差异的理论分析。经典的工作记忆模型得到了发展,引入情境缓冲系统作为多成分模型的一部分,这是对个体经验的重视。传统衡量个体差异的主要指标短时记忆容量(组块)、智力(g)等逐步被工作记忆指标发展替代:如执行性注意控制、工作记忆广度等。工作记忆的个体差异本质上是否与智力的差异具有同构性的焦点引起了广泛关注。在今后的研究中,关于领域一般性与特殊性的及神经生理学等方向可能是厘清工作记忆个体差异的主流趋势。     

Working memory involvement in stuttering: exploring the evidence and research implications

Several studies of utterance planning and attention processes in stuttering have raised the prospect of working memory involvement in the disorder. In this paper, potential connections between stuttering and two elements of Baddeley's [Baddeley, A. D. (2003). Working memory: Looking back and looking forward. Neuroscience, 4, 829-839] working memory model, phonological memory and central executive, are posited. Empirical evidence is drawn from studies on phonological memory and dual-task performance among children and adults who stutter to examine support for the posited connections. Implications for research to examine working memory as one of the psycholinguistic bases of stuttering are presented. EDUCATIONAL OBJECTIVES: The reader will learn about and be able to: (1) appraise potential relationships between working memory and stuttering; (2) evaluate empirical evidence that suggests the possibility of working memory involvement in stuttering; and (3) identify research directions to explore the role of working memory in stuttering.     

Working memory capacity and the spacing effect in cued recall

Spacing repetitions typically improves memory (the spacing effect). In three cued recall experiments, we explored the relationship between working memory capacity and the spacing effect. People with higher working memory capacity are more accurate on memory tasks that require retrieval relative to people with lower working memory capacity. The experiments used different retention intervals and lags between repetitions, but were otherwise similar. Working memory capacity and spacing of repetitions both improved memory in most of conditions, but they did not interact, suggesting additive effects. The results are consistent with the ACT-R model’s predictions, and with a study-phase recognition process underpinning the spacing effect in cued recall.     

Working Memory Capacity and the Development of Quantitative Central Conceptual Structures

Abstract

This article reconsiders Case’s theory of central conceptual structures (CCS), examining the relation between working memory and the acquisition of quantitative CCS. The lead hypothesis is that the development of working memory capacity shapes the development of quantitative concepts (whole and rational numbers). Study I, with 779 children from preschool to grade 5, validated a measure of the whole number CCS and found that children’s understanding of whole number advances by one developmental level per additional unit of working memory capacity. Study II, with 92 sixth- and seventh-graders, found that a test of the rational number CCS was predicted by working memory capacity and, to a lesser extent, by intrusion errors in the listening span. We also identified 2 subsets of items that demand a capacity of 4 or 5 units, respectively. Overall, the results support Case’s CCS theory and clarify the role of working memory in the acquisition of numerical concepts. The relevance of these results in relation to the current debate is discussed, with extensive connections to other current theories of whole or rational number comprehension.     

Contrasting single and multi-component working-memory systems in dual tasking

Working memory can be a major source of interference in dual tasking. However, there is no consensus on whether this interference is the result of a single working memory bottleneck, or of interactions between different working memory components that together form a complete working-memory system. We report a behavioral and an fMRI dataset in which working memory requirements are manipulated during multitasking. We show that a computational cognitive model that assumes a distributed version of working memory accounts for both behavioral and neuroimaging data better than a model that takes a more centralized approach. The model’s working memory consists of an attentional focus, declarative memory, and a subvocalized rehearsal mechanism. Thus, the data and model favor an account where working memory interference in dual tasking is the result of interactions between different resources that together form a working-memory system.     

Working memory capacity predicts search accuracy for novel as well as repeated targets

Visual search behaviour is guided by mental representations of targets that direct attention toward relevant features in the environment. Electrophysiological data suggests these target templates are maintained by visual working memory during search for novel targets and rapidly transfer to long term memory with target repetition. If this account is correct, an individual’s working memory capacity should be more predictive of search performance for novel targets than repeated targets. Across six experiments, we tested this hypothesis using both single (Experiments 5 and 6) and multiple (Experiments 1–4) target search tasks with three different types of stimuli (real world objects, letters, and triple conjunction shapes). Each target set was repeated for six consecutive trials. In addition, we estimated visual working memory capacity using a change detection working memory task. Overall, working memory capacity did not predict response time or efficiency in the visual search task. However, working memory capacity was equally predictive of search accuracy for both novel and repeated targets. These results suggest that working memory requirements do not substantially differ between novel and repeated target search, and working memory capacity may continue to play an important role in the encoding or maintenance of target representations after they are presumed to be in long term memory.     

Specifying the attentional selection that moderates the fearlessness of psychopathic offenders

Our previous research demonstrated that psychopathy-related fear deficits involve abnormalities in attention that undermine sensitivity to peripheral information. In the present study, we specified this attention-mediated abnormality in a new sample of 87 prisoners assessed with Hare's Psychopathy Checklist-Revised (Hare, 2003). We measured fear-potentiated startle (FPS) under four conditions that crossed attentional focus (threat vs. alternative) with early versus late presentation of threat cues. The psychopathic deficit in FPS was apparent only in the early-alternative-focus condition, in which threat cues were presented after the alternative goal-directed focus was established. Furthermore, psychopathy interacted with working memory capacity in the late-alternative-focus condition, which suggests that individuals high in psychopathy and working memory capacity were able to maintain a set-related alternative focus that reduced FPS. The results not only provide new evidence that attention moderates the fearlessness of psychopathic individuals, but also implicate an early attention bottleneck as a proximal mechanism for deficient response modulation in psychopathy.