儿童执行功能与算术认知策略的关系

对35名小学2年级儿童的四种执行功能与有无工作记忆负荷两种情况下算术认知策略表现之间的关系进行了探讨.结果表明,双任务协调功能与工作记忆负荷增加时放弃策略的使用次数具有显著负相关;策略转换功能越强的儿童.算术认知策略的使用越灵活;抑制功能强的儿童在提取策略的相关表现上更好;记忆更新功能与工作记忆负荷增加时策略执行的正确率具有显著正相关.这说明,执行功能与儿童算术认知策略之间存在着特定的联系.     

工作记忆中央执行对儿童算术认知策略的影响

运用“双重任务”范式,以113名小学二年级儿童为被试,考察了儿童工作记忆的中央执行对算术认知策略表现的影响。结果表明:中央执行对儿童算术认知策略的选择产生了针对性的影响,集中表现在外部策略、支持性策略和猜测放弃策略上。中央执行干扰使策略执行的正确率下降、反应时增加。在简单加法任务上,中央执行影响了外部策略和支持性策略的选择频次;在复杂任务中,这种影响体现在外部策略和放弃策略上。无论是简单任务还是复杂任务,中央执行的干扰都造成了策略整体执行效果的下降。     

基于中央执行功能的儿童工作记忆可塑性机制

近期的研究发现儿童的工作记忆能力具有一定的可塑性。研究者采用双盲对照实验设计, 通过改编的工作记忆广度、N-back、活动记忆和GO-NOGO等任务对15岁以下的正常儿童和特殊儿童(多动症、智力低下等)的工作记忆能力进行训练, 训练的周期一般为15~30天不等, 每天训练时长约15~25分钟。研究结果发现, 工作记忆训练不仅可以提高儿童的工作记忆能力, 而且还可以迁移至其它高级认知功能(流体智力、数学能力等), 甚至可以改善多动症儿童的临床症状。研究者还发现这种训练效应可以保持3~6个月。通过工作记忆中央执行功能的训练, 是否可以促进儿童认知功能的发展？儿童认知功能的可塑性表现为短暂的提高还是促进认知发展？中央执行功能的训练如何影响儿童认知加工过程的发展？这些问题的回答对于近一步探索认知活动和认知神经的可塑性具有一定的理论意义。可以为工作记忆缺陷儿童的临床干预和治疗提供有效的工具, 具有实践意义。     

工作记忆成分的年龄相关差异对算术策略运用的预测效应

采用选择/无选范式,借助工作记忆成套测验,在两位数乘法估算问题中探讨了工作记忆系统各成分对不同年龄段个体算术策略运用的预测效应。结果显示:(1)工作记忆的不同成分与年龄之间存在明显的相关。表现为,除视空模板成分外,其他各成分得分随着年龄增长而呈现上升趋势;(2)估算策略运用中,年龄与策略选择显著相关,表现为随着年龄增长,策略选择表现明显提高;(3)估算策略运用中,不同年龄个体的工作记忆不同成分和策略选择表现出不同的联系,中央执行均显示出显著的预测效应,语音环路和视空模板的预测效应均不显著。不同年龄个体的工作记忆不同成分对策略执行的预测效应均不显著。上述发现对于深刻理解工作记忆系统在算术认知策略运用中的作用机制具有重要理论含义。     

工作记忆广度对儿童算术认知策略的影响

选取113名小学二年级儿童为被试,探讨了工作记忆广度对儿童算术认知策略的影响。结果表明:不同工作记忆广度儿童在出声、手动、心里数数、竖式、分解、凑整、猜测和放弃策略的选择频次上具有显著差异,在算术认知策略的执行上,差异明显;随着工作记忆广度的增加,出声策略表现出了波动型的变化曲线,手动、心里数数、凑整和猜测策略具有门槛型的变化趋势,竖式、分解和放弃策略呈现出阶梯状的变化特点。这些结果说明,儿童算术认知策略表现受到其工作记忆容量明显的限制性作用。     

2～3.5岁儿童执行功能发展特点及其言语能力的影响

2~3.5岁是婴儿成长到幼儿的重要发展转折期,也是儿童执行功能及言语能力的发展萌芽期。研究通过测查北京市81名2~3.5岁儿童在固定盒子任务、搭积木任务、A非B任务和皮博迪图片词汇测验上的表现,探究了该年龄段儿童执行功能的发展特点、各成分间的内部关系、以及言语能力对执行功能的影响。结果发现:(1)在2~3.5岁期间,除认知灵活性外,儿童的工作记忆与抑制控制均快速发展,其中,2.5岁前后是工作记忆与抑制控制的重要发展时期;(2)在2~3岁期间,认知灵活性与工作记忆之间相关密切,在3~3.5岁期间,认知灵活性与抑制控制的相关密切,3岁是儿童执行功能内部成分关系的重要发展转折期;(3)在2~3.5岁期间,儿童言语能力呈现快速发展,并且言语能力对该年龄段执行功能各成分间关系产生一定的影响,但不同言语能力的儿童在执行功能各成分的表现并没有显著差异。     

学前期儿童执行功能与攻击性行为的关系：认知共情的中介作用

学前期儿童的攻击性行为与其执行功能密切相关，而共情则可能是二者产生联系的关键。因此，本研究拟探讨学前期儿童执行功能(研究1)及其子成分(研究2)与其攻击性行为之间的关系，并考察共情的中介作用。结果发现，学前期儿童的攻击性行为与其整体执行功能、抑制控制和工作记忆显著负相关，认知共情分别在攻击性行为与整体执行功能、抑制控制和工作记忆的关系间起中介作用。结果表明，学前期儿童的执行功能是其攻击性行为的限制器，抑制控制和工作记忆起主要作用；学前期儿童的执行功能通过促进认知共情从而抑制其攻击性行为。     

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。     

一般流体智力研究中工作记忆与注意的关系

随着对一般流体智力的研究逐步深入,研究者们认为了解工作记忆与注意的相互关系是解决一般流体智力与前二者结构关系的关键。由于工作记忆系统中中央执行器的功能尚不明确,注意控制能力与工作记忆的关系难以确定。研究者中存在两种不同的观点：一种认为两者之间存在着密切的互动,另一种则认为两者就是同功同构的一个认知成分。     

工作记忆容量与儿童算术认知加工

工作记忆容量的差别是个体认知差异的一个重要方面。工作记忆容量在多种运算规则下与运算技能、概念性知识等因素交织在一起共同对儿童的算术认知加工产生影响,并且它是数学学习不良儿童学习困难的一个重要影响因素。同时,儿童的工作记忆容量本身也受到多种因素的制约,进而影响儿童的算术认知成绩。     

Susceptibility of spatial and verbal working memory to demands of the central executive

We used a dual-task paradigm to examine the degree to which domain-specific spatial and verbal subsystems depend on the domain-general central executive. Forty participants were asked to retain spatial or verbal information while performing a concurrent secondary task related to simple arithmetic. The secondary tasks consisted of three cognitive processes: single-digit addition, a digit-carrying operation, and digit reading. The single-digit addition and carry operation include central executive functioning, while digit reading relies solely on the phonological loop. The single-digit addition caused a performance decrement on the spatial working memory task, while the digit reading impaired performance on the verbal working memory task. The carry operation interfered with recall accuracy on both working memory tasks. The spatial working memory task was significantly correlated with the verbal working memory task only when the secondary task was more demanding on the central executive. Our results suggest that spatial working memory rather than verbal working memory is susceptible to failure of central executive functioning and that the central executive plays an important role in regulating the cognitive demands of different domains.     

The roles of the central executive and visuospatial storage in mental arithmetic: A comparison across strategies

Previous research has demonstrated that working memory plays an important role in arithmetic. Different arithmetical strategies rely on working memory to different extents—for example, verbal working memory has been found to be more important for procedural strategies, such as counting and decomposition, than for retrieval strategies. Surprisingly, given the close connection between spatial and mathematical skills, the role of visuospatial working memory has received less attention and is poorly understood. This study used a dual-task methodology to investigate the impact of a dynamic spatial n-back task (Experiment 1) and tasks loading the visuospatial sketchpad and central executive (Experiment 2) on adults' use of counting, decomposition, and direct retrieval strategies for addition. While Experiment 1 suggested that visuospatial working memory plays an important role in arithmetic, especially when counting, the results of Experiment 2 suggested this was primarily due to the domain-general executive demands of the n-back task. Taken together, these results suggest that maintaining visuospatial information in mind is required when adults solve addition arithmetic problems by any strategy but the role of domain-general executive resources is much greater than that of the visuospatial sketchpad.     

High-performers use the phonological loop less to process mental arithmetic during working memory tasks

This study investigated the effects of three working memory components—the central executive, phonological loop, and visuospatial sketchpad—on performance differences in complex mental arithmetic between individuals. Using the dual-task method, we examined how performance during two-digit addition was affected by load on the central executive (random tapping condition), phonological loop (articulatory suppression condition), and visuospatial sketchpad (spatial tapping condition) compared to that under no load (control condition) in high- and low-performers of complex mental arithmetic in Experiment 1. Low-performers showed an increase in errors under the random tapping and articulatory suppression conditions, whereas high-performers showed an increase of errors only under the random tapping condition. In Experiment 2, we conducted similar experiments on only the high-performers but used a shorter presentation time of each number. We found the same pattern for performing complex mental arithmetic as seen in Experiment 1. These results indicate that high-performers might reduce their dependence on the phonological loop, because the central executive enables them to choose a strategy in which they use less working memory capacity.     

Representation and working memory in early arithmetic

Working memory has been implicated in the early acquisition of arithmetic skill, but the relations among different components of working memory, performance on different types of arithmetic problems, and development have not been explored. Preschool and Grade 1 children completed measures of phonological, visual-spatial, and central executive working memory, as well as nonverbal and verbal arithmetic problems, some of which included irrelevant information. For preschool children, accuracy was higher on nonverbal problems than on verbal problems, and the best and only unique predictor of performance on the standard nonverbal problems was visual-spatial working memory. This finding is consistent with the view that most preschoolers use a mental model for arithmetic that requires visual-spatial working memory. For Grade 1 children, performance was equivalent on nonverbal and verbal problems, and phonological working memory was the best predictor of performance on standard verbal problems. For both age groups, problems with added irrelevant information were substantially more difficult than standard problems, and in some cases measures of the central executive predicted performance. Assessing performance on different components of working memory in conjunction with different types of arithmetic problems provided new insights into the developing relations between working memory and how children do arithmetic.     

中央执行负荷对成人估算策略运用的影响

随机选取128名大学生为被试, 运用选择/无选法研究范式, 考察了不同中央执行负荷对估算策略运用的影响。结果发现：(1)中央执行负荷不影响策略分布; (2)策略运用条件、中央执行负荷影响策略执行。主次一致任务, 负荷对策略执行反应时的影响随负荷强度增大而增大, 对策略执行精确度影响不大; 而对主次不一致任务, 低负荷对策略执行反应时及精确度影响都不明显; (3)策略运用条件、中央执行负荷影响策略选择。负荷强度对策略选择反应时起重要作用, 只有当次级任务负荷高时, 干扰作用才明显; (4)成人的策略选择适应性受负荷强度的影响。无负荷条件下个体策略适应性更好。     

The development of strategy use in elementary school children: working memory and individual differences

The current study tested the development of working memory involvement in children's arithmetic strategy selection and strategy efficiency. To this end, an experiment in which the dual-task method and the choice/no-choice method were combined was administered to 10- to 12-year-olds. Working memory was needed in retrieval, transformation, and counting strategies, but the ratio between available working memory resources and arithmetic task demands changed across development. More frequent retrieval use, more efficient memory retrieval, and more efficient counting processes reduced the working memory requirements. Strategy efficiency and strategy selection were also modified by individual differences such as processing speed, arithmetic skill, gender, and math anxiety. Short-term memory capacity, in contrast, was not related to children's strategy selection or strategy efficiency.     

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.     

内隐序列学习与中央执行功能的关系

内隐序列学习与一般认知的关系一直处于争议之中。近年来,越来越多的研究显示内隐序列学习与工作记忆（尤其是中央执行功能）存在显著关联。基于此,本研究通过两个实验来探测两者的相关及机制。实验1从行为与脑电两个角度探讨经典位置序列学习与中央执行功能的相关,发现经典位置序列学习的内隐习得量与中央执行功能的抑制、刷新功能的强度呈负相关,与转换功能没有显著相关,脑电结果也支持了这一结论。实验2在内隐序列学习中加入认知冲突来增加中央执行功能的负荷。结果发现在高抑制功能负荷任务条件下,内隐习得量与抑制功能强度的相关性发生了反转,进一步证明内隐序列学习与中央执行功能的抑制子成分在脑功能上的关系：不同条件下呈现竞争、协作等不同状态。