Random Generation and the Executive Control of Working Memory

A series of experiments explores the capacity for generating sequences of random responses, relating it to the central executive component of working memory. Experiment 1 shows a broadly similar pattern of redundancy increasing with speed of generation for both the verbal generation of digits and the manual pressing of keys. In both cases deviations from randomness are shown to reflect the increasing use of a limited number of stereotyped response sets. The remaining experiments use keyboard generation. Experiment 2 demonstrates that concurrent immediate serial recall decreases randomness, and that longer recall sequences produce less random output. Experiments 3 and 4 show that whereas simple counting has no effect on randomness, serial recall, semantic category generation, and concurrent digit generation have substantial effects, and a concurrent fluid intelligence test has the greatest influence on the randomness of key pressing. It is suggested that the task of random generation resembles that of category fluency because it requires the subject to switch retrieval plans and inhibit repetition. On this basis it is predicted that a task involving repeated switching of categories will interfere with generation, despite being predictable and having a low memory load. Experiments 5 and 6 confirm this prediction. Strengths and limitations of the switching hypothesis are discussed, as are the implications of our results for the analysis of executive processes.     

Working Memory Capacity as Executive Attention

Performance on measures of working memory (WM) capacity predicts performance on a wide range of real-world cognitive tasks. I review the idea that WM capacity (a) is separable from short-term memory, (b) is an important component of general fluid intelligence, and (c) represents a domain-free limitation in ability to control attention. Studies show that individual differences in WM capacity are reflected in performance on antisaccade, Stroop, and dichotic-listening tasks. WM capacity, or executive attention, is most important under conditions in which interference leads to retrieval of response tendencies that conflict with the current task.     

工作记忆中央执行功能的老化研究

采用注意焦点、任务转换、强制刷新三种任务范式分别测量了60岁以上老年人和20岁左右年轻人的注意焦点功能、内容调控功能、任务管理功能.分析三种工作记忆中央执行功能的年龄差异.结果发现:1.注意焦点没有表现出明显的年龄差异;任务转换和强制刷新成绩在青年和老年被试之间差异显著.2.注意焦点成绩与任务转换成绩.强制刷新成绩之间无显著相关,任务转换成绩与强制刷新成绩呈现中度相关.研究结果表明,工作记忆的执行功能是一个包括多种相对独立子成分的系统,不同执行功能老化轨迹不尽相同.     

Inhibitory Control and Working Memory in Post-Institutionalized Children

Inhibitory control and working memory were examined in post-institutionalized (PI) children adopted into United States families from Russian institutions. The PI sample originated from institutions that were less severely depriving than those represented in previous studies and approximated the level of psychosocial deprivation, which is characterized by adequate physical resources but a lack of consistent and responsive caregiving. PI children (N?=?75; 29 male) ranged in age from 8–17 years (M?=?12.97; SD?=?3.03) and were grouped according to whether they were adopted after 14 months or before 9 months. A non-adopted comparison group (N?=?133; 65 male) ranged in age from 8–17 years (M?=?12.26; SD?=?2.75). PI children adopted after 14 months of age displayed poorer performance on the stop-signal and spatial span tasks relative to PI children adopted before 9 months of age after controlling for age at assessment. The two PI groups did not differ in their performance on a spatial self-ordered search task. Older-adopted PI children also showed poorer spatial span task performance compared to non-adopted children, but younger-adopted PI children did not. Task performance was significantly associated with parent-rated hyperactive-impulsive behavior in everyday contexts. These findings suggest that exposure to prolonged early institutional deprivation may be linked with inhibitory control and working memory difficulties years after adoption.     

Investigating Executive Working Memory and Phonological Short-Term Memory in Relation to Fluency and Self-Repair Behavior in L2 Speech

This paper reports the findings of a study investigating the relationship of executive working memory (WM) and phonological short-term memory (PSTM) to fluency and self-repair behavior during an unrehearsed oral task performed by second language (L2) speakers of English at two levels of proficiency, elementary and lower intermediate. Correlational analyses revealed a negative relationship between executive WM and number of pauses in the lower intermediate L2 speakers. However, no reliable association was found in our sample between executive WM or PSTM and self-repair behavior in terms of either frequency or type of self-repair. Taken together, our findings suggest that while executive WM may enhance performance at the conceptualization and formulation stages of the speech production process, self-repair behavior in L2 speakers may depend on factors other than working memory.     

同声传译过程中的工作记忆与双语控制研究

同声传译是一项受时间限制的高度复杂的双语活动,译员在接收原语输入的同时要进行译入语输出。同传中译员要经过原语接收、理解、转换、译入语表达等一系列过程。近年来有研究者开始尝试同声传译过程中的工作记忆研究,认为工作记忆是同传作业的关键因素,并提出工作记忆在同传中的扩展模型。本文主要就同声传译的关键特征与多任务处理模型、工作记忆在同传中的作用机制和译入语提取时的双语控制机制等问题进行简要介绍,并提出了进一步的研究思路。     

Scheduling Processes in Working Memory: Instructions Control the Order of Memory Search and Mental Arithmetic

Humans must often use working memory to execute processes one at a time because of its limited capacity. Two experiments tested where limits in access to working memory occur. Subjects searched a short-term memory set for one stimulus digit and performed mental arithmetic with another stimulus digit. In one experiment, they were told to carry out the mental arithmetic before the memory search and to make the arithmetic response first. In the other, they were instructed to perform the tasks in the opposite order. The overt responses were executed in the prescribed order. Moreover, the covert working memory processes were executed in the prescribed order, as revealed by a critical path network analysis of reaction times. Results are explained in terms of a double-bottleneck model in which central processes and responses are constrained to be carried out for one task at a time.     

时序信息和空间信息在工作记忆中的分离存储

采用相对新近性判断范式（judgments of relative recency）,通过三个实验探讨了工作记忆中时序信息和空间信息的存储方式及其关系。实验一比较了有无空间线索两种条件下时序信息的记忆绩效,结果发现,有无空间线索并不影响对时序信．E-的记忆。实验二和实验三通过控制刺激呈现的视野范围和减少呈现位置的不确定性来利化空间线索,结果表明,时序信息的记忆绩效也不受空间线索的影响。由此推论,工作记忆中的时序信息和空间信息是分离编码存储的,加入空间线索并不能提高时序信息的记忆绩效。     

The Neural Correlates of Updating Information in Verbal Working Memory

The aim of the present study was to re-examine cerebral areas subserving the updating function of the central executive with a running span task requiring subjects to watch strings of consonants of unknown length and then to recall serially a specific number of recent items. In order to dissociate more precisely the updating process from the storage function, a four-item instead of a six-item memory load was used, contrary to our previous study (Salmon et al., 1996). In addition, a serial recall procedure was preferred to a recognition procedure in order to suppress the use of visuospatial strategies. The most significant increase of rCBF occurred in the left frontopolar cortex (Brodmann's area 10), spreading to the left middle frontal (Brodmann's area 46). Results suggest that frontopolar activation underlies an updating process in working memory.     

Protection, Paradox, and Pretending

This paper proposes that psychopathology in children can be the result of an incongruity in the hierarchical organization of the family. The parents are in a superior position to the child by the fact of being parents, and yet the problem child assumes a superior position to the parents by protecting them through symptomatic behavior that often expresses metaphorically the parents' difficulties. The paper describes three paradoxical strategies for arranging that the parents solve the presenting problem of the child and the incongruity in the family hierarchy. The therapeutic techniques described are characterized by the use of communication modalities, such as dramatizations, pretending, and make-believe, that are appropriate to children.     

Phonology, Working Memory, and Foreign-language Learning

Three tasks were used to predict English learning by Finnish children over a three-year period. In the pseudoword repetition task the pupils had to repeat aloud tape-recorded pseudowords sounding like Finnish or English. In the pseudoword copying task the pupils saw strings of letters resembling Finnish or English words and copied them when they had disappeared from view. When comparing syntactic-semantic structures, the pupils had to find the syntactically matching pairs from two sets of Finnish sentences. Repetition and copying accuracy and the ability to compare syntactic-semantic structures predicted English learning. Intercorrelations between test scores and English and mathematics grades suggest that repetition and copying accuracy were specifically related to language learning. It is concluded that the ability to represent unfamiliar phonological material in working memory underlies the acquisition of new vocabulary items in foreign-language learning.     

Adaptive Memory: Fitness Relevance and the Hunter-Gatherer Mind

ABSTRACT— Recent studies suggest that human memory systems are "tuned" to remember information that is processed in terms of its fitness value. When people are asked to rate the relevance of words to a survival scenario, performance on subsequent surprise memory tests exceeds that obtained after most other known encoding techniques. The present experiments explored this effect using survival scenarios designed to mimic the division of labor thought to characterize early hunter-gatherer societies. It has been suggested that males and females have different cognitive specializations due to the unique survival tasks (hunting and gathering, respectively) they typically performed during periods of human evolution; the present experiments tested whether such specializations might be apparent in memory for words rated for relevance to these activities. Males and females were asked to rate the relevance of random words to prototypical hunting and gathering scenarios or to matched, non-fitness-relevant control scenarios (gathering food on a scavenger hunt or in a hunting contest). Surprise retention tests revealed superior memory for the words when they were rated for relevance to hunting and gathering scenarios, compared with when they were rated for relevance to the control scenarios, but no sex differences were found in memory performance.     

Agency,Consciousness, and Executive Control

On the Causal Theory of Action (CTA), internal proper parts of an agent such as desires and intentions are causally responsible for actions. CTA has increasingly come under attack for its alleged failure to account for agency. A recent version of this criticism due to François Schroeter proposes that CTA cannot provide an adequate account of either the executive control or the autonomous control involved in full-fledged agency. Schroeter offers as an alternative a revised understanding of the proper role of consciousness in agency. In this paper we criticize Schroeter’s analysis of the type of consciousness involved in executive control and examine the way in which the conscious self allegedly intervenes in action. We argue that Schroeter’s proposal should not be preferred over recent versions of CTA.     

A Comparative Study of Shifting Ability,Inhibitory Control and Working Memory in Monolingual and Bilingual Children

It is now well documented that the linguistic development of bilingual children is, in many respects, different from that of their monolingual peers. Yet, there is substantial evidence in cognitive psychology that the effect of bilingualism is not merely restricted to the linguistic competence of individuals. Recent literature on bilingualism suggests that certain aspects of children’s cognitive development can be positively affected by the bilingual experience. The aim of the present study was to investigate the potential effects of bilingual experience on young children’s executive processing. A total of 67 preschool children belonging to two groups including 36 Persian–Turkish bilingual children and 31 Persian monolingual children participated in the study. They were matched for their verbal proficiency and then were compared on three executive function tasks including shifting ability, inhibitory control and working memory. Results showed that bilingual children outperformed monolinguals on both shifting and inhibitory control tasks. However, both groups performed similarly on working memory tasks. The findings are interpreted in terms of the enhanced ability of bilingual children in various executive functions processing.     

语文学习困难儿童的短时记忆、工作记忆和加工速度

短时记忆、工作记忆和加工速度反映了不同的认知加工.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、短时记忆和加工速度的差异.结果发现,与控制组相比,语文学习困难儿童在工作记忆、短时记忆和加工速度方面均存在明显的不足,但短时记忆和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的不足,与视空间工作记忆能力无关,语文学习困难与特定的工作记忆(言语工作记忆)能力的不足有关.工作记忆缺陷的原因在于存储能力的不足,而不是加工效率的缺陷造成的.     

The Training Effect of Working Memory Based on Central Executive System Intervention in Older Adults: A Randomized Controlled Study

This article aims to investigate the training effect of working memory in older adults. A total of 43 older adults ranging in age from 75 to 95 were recruited to participate in the study. A battery of tests regarding central executive function, working memory, and primary mental ability were administered in the pretest phase. A total of 22 of the older participants were randomly selected as the intervention group. Thirteen days after the pretest, the same tests were administered to all of the participants. The results showed that (1) the differences in the pretest and posttest gains in the task-switching tests were not significant between the intervention group and the control group; (2) the performance of the intervention group on the operation working memory span test and the graphical reasoning test showed a significant improvement after the intervention compared with the control group who did not receive the intervention. We can conclude that the working memory of old adults may be improved by an intervention targeting the central executive system. However, this possibility needs further investigation.