Distributing mathematical practice of third and seventh graders: Applicability of the spacing effect in the classroom

We examined the effect of distributed practice on the mathematical performance of third and seventh graders (N = 213) in school. Students first received an introduction to a mathematical topic, derived from their curriculum. Thereafter, they practiced in one of two conditions. In the massed condition, they worked on three practice sets in 1 day. In the distributed condition, they worked on one practice set per day for 3 consecutive days. Bayesian analyses of the performance in two follow‐up tests 1 and 6 weeks after the last practice set revealed a positive effect of distributed practice as compared with massed practice in Grade 7. In Grade 3, a positive effect of distributed practice was supported by the data only in the test 1 week after the last practice set. The results suggest that distributed practice is a powerful learning tool for both elementary and secondary school students in the classroom.     

Concepts as Semantic Pointers: A Framework and Computational Model

The reconciliation of theories of concepts based on prototypes, exemplars, and theory‐like structures is a longstanding problem in cognitive science. In response to this problem, researchers have recently tended to adopt either hybrid theories that combine various kinds of representational structure, or eliminative theories that replace concepts with a more finely grained taxonomy of mental representations. In this paper, we describe an alternative approach involving a single class of mental representations called “semantic pointers.” Semantic pointers are symbol‐like representations that result from the compression and recursive binding of perceptual, lexical, and motor representations, effectively integrating traditional connectionist and symbolic approaches. We present a computational model using semantic pointers that replicates experimental data from categorization studies involving each prior paradigm. We argue that a framework involving semantic pointers can provide a unified account of conceptual phenomena, and we compare our framework to existing alternatives in accounting for the scope, content, recursive combination, and neural implementation of concepts.     

Effects of Interspersed Brief Problems on Students' Endurance at Completing Math Work

An alternating treatments design was used to compare the effects of baseline, interspersed brief problems, and interspersed brief problems plus token reinforcement on students' endurance while completing math worksheets. By pairing the completion of brief problems with token reinforcement, the role of problem completion as a conditioned reinforcer was examined consistent with the discrete task completion hypothesis. Four 5th grade students who were low achieving in math participated. Each day the students completed a stack of math worksheets containing 3-digit by 3-digit addition problems with or without interspersed single-digit problems for 10 min. Dependent measures included total digits correct per session and during each min of the 10 min work period (i.e., a measure of endurance). Results indicated that total digits correct per session was highest during the interspersal plus reinforcement condition followed by interspersal and then baseline for three of the four students. In addition, both interspersal conditions resulted in greater endurance than baseline. Limitations of the current study and implications for increasing students' persistence on classroom tasks are discussed.     

Task switching: a PDP model

When subjects switch between a pair of stimulus-response tasks, reaction time is slower on trial N if a different task was performed on trial N - 1. We present a parallel distributed processing (PDP) model that simulates this effect when subjects switch between word reading and color naming in response to Stroop stimuli. Reaction time on "switch trials" can be slowed by an extended response selection process which results from (a) persisting, inappropriate states of activation and inhibition of task-controlling representations; and (b) associative learning, which allows stimuli to evoke tasks sets with which they have recently been associated (as proposed by Allport & Wylie, 2000). The model provides a good fit to a large body of empirical data, including findings which have been seen as problematic for this explanation of switch costs, and shows similar behavior when the parameters are set to random values, supporting Allport and Wylie's proposal.     

EXPERIMENTER CALCULATION ERRORS: A POTENTIAL FACTOR AFFECTING INTERPRETATION OF RESULTS1

Following a study of socially withdrawn children, it was noted that checks of experimenter calculations indicated discrepancies. The present study investigated the magnitude and direction of experimenter errors in data computations. Two full-time research assistants, who served as experimenters, processed the behavioral observation data. These experimenters were referred to as the subjects in this study. Standard data values, against which the subjects' computations were compared, were established by two other research assistants and a computer staff. The results indicated that experimenters' original data values disagreed with the standard data values. The daily errors showed considerable variability for both experimenters. The specific factors accounting for this variability could not be identified, although frequency of experimenter responses required to obtain rate and duration data, time spent calculating, and complexity of task were suggested as possible contributing variables. While disagreements occurred across all experimental days, the magnitude of differences was generally small. An examination of direction of differences in both experimenters' data showed no systematic trends in favor of the experimental hypothesis. Rather, there appeared to be a trend in the other direction. This study suggests that the same research decisions would have been made during the original investigation using either set of data.     

对语言神经机制的新认识

本文针对语言神经机制的研究现状,分析了失语症和裂脑人研究的成果,并且较为详细地介绍了最近十年脑功能成像得到的有关语言神经活动的新成就,在此基础上,提出了一种动态分布式竞争的解释理论,用来解释语言神经活动现象和规律,并进一步借以说明言语意识的产生机制。     

Taking a Systems View of Creativity: On the Right Path Toward Understanding

In our 2010 Annual Review paper, Teresa Amabile and I argued that a virtual explosion of topics, viewpoints, and methodologies had muddied the investigative waters. Few, if any, “big” questions were being pursued by a critical mass of creativity researchers. Instead, investigators in one subfield seemed entirely unaware of advances in another. We saw a crucial need for a systems view of creativity and we encouraged investigators to recognize that creativity arises from a complex web of interrelated forces operating at multiple levels. Seven years have passed since the publication of that paper, and an examination of the most current research suggests that a growing number of publications are now reflecting a systems approach as well as a multidisciplinary perspective.     

交互进化计算对焦虑测量的适用性探析

大量的研究用stroop色词命名任务和点探测任务等经典的情绪研究方法证明了社交焦虑个体情绪识别的特殊性。该研究采用IEC(交互进化计算)的方法, 研究了焦虑组和对照组(低焦虑组)在情绪感知动态范围上的差异性。实验要求第一组被试利用给出的IEC情绪识别光影系统设计出符合实验维度(高兴、恐惧)的图片, 并让第二组被试对图片进行评估, 得出每幅图片的心理数值范围。实验结果说明IEC可以适用于常规优化系统之外的一个新领域—— 心理健康的测量,同时也表明社交焦虑个体的情绪感知动态范围窄于正常人。