Choice and multiple reinforcers

Pigeons chose between equivalent two-component mixed and multiple terminal-link schedules of reinforcement in the concurrent-chains procedure. The pigeons preferred the multiple schedule over the mixed when the components of the compound schedules were differentiated in terms of density of reinforcement, but the pigeons were indifferent when the components were differentiated in terms of number of reinforcers per cycle. Taken together, these results indicate that a local variable, the interval to the first reinforcer, but not a molar variable, the number of reinforcers, was sufficient to differentiate the components and thereby evoke preference.     

Latent roots of random data correlation matrices with squared multiple correlations on the diagonal: A monte carlo study

In order to make the parallel analysis criterion for determining the number of factors easy to use, regression equations for predicting the logarithms of the latent roots of random correlation matrices, with squared multiple correlations on the diagonal, are presented. The correlation matrices were derived from distributions of normally distributed random numbers. The independent variables are log (N–1) and log {[n(n–1)/2]–[(i–1)n]}, whereN is the number of observations;n, the number of variables; andi, the ordinal position of the eigenvalue. The results were excellent, with multiple correlation coefficients ranging from .9948 to .9992.This research was supported by the Office of Naval Research under Contract N00014-67-A-0305-0012, Lloyd G. Humphreys, principal investigator, and by the Department of Computer Science of which Richard G. Montanelli, Jr., is a member.     

Dimensional stimulus control following brief wavelength training

Pigeons with extensive training pecking a key illuminated by a white line then had brief training with the key illuminated by 555 nanometers. This was immediately followed by a wavelength generalization test in extinction. Dimensional stimulus control about the training wavelength increased with the duration and number of reinforcements given on variable-interval 30-sec and variable-interval 10-sec schedules in Experiment I. In Experiment II, dimensional stimulus control was obtained after only 4 min of wavelength training from birds with prior and independent discrimination training. Experiment III provided groups equated in number of reinforcers with groups in Experiment I and two 8-min duration groups. Analyses, which included results from both Experiments I and III, showed that dimensional stimulus control increased: (a) more rapidly as a function of the duration of variable-interval 10-sec than variable-interval 30-sec reinforcement; (b) at the same rate across variable-interval reinforcement schedules, as a function of the number of reinforcers available during brief wavelength training.     

友伴人际品格对儿童人际品格的影响:友伴数量的调节作用及儿童群体差异

友伴是儿童发展的重要影响源。本研究从儿童积极发展的视角探讨友伴人际品格（仁慈和公正）对儿童人际品格的影响及友伴数量在其中的调节作用,并检验了儿童的群体（学段、性别、是否独生）差异状况。研究采用班级同伴提名法及儿童品格调查问卷对1555名4~9年级儿童及其互提名友伴展开调查。结果发现：（1）友伴仁慈和公正显著预测所有儿童群体的仁慈和公正;（2）儿童的友伴数量更多时,友伴公正对其公正的预测作用更显著;该调节效应仅体现在初中生和男生群体上。研究结果表明,儿童与具有积极品格特征的友伴交往对其积极品格的发展至关重要,且对于特定群体（如初中生、男生）,与越多具有积极品质的友伴交往,其受到的积极影响越大。     

非符号数量表征和符号分数表征的关系

个体学习符号分数的一个关键是能对其数值形成准确表征。现有研究假设符号分数表征的认知基础是人类自婴幼儿期就具有的非符号数量表征(如表征两个集合各自的数量, 或两个数量的比例)。其证据包括表征非符号数量(尤其是非符号数量比例关系)和表征符号分数在行为和大脑神经活动层面上都表现出相关性。然而要说明非符号数量表征是符号分数表征的认知基础, 还需更多研究表明两者在数量概念上的独特相关和因果联系, 并阐明符号分数表征形成的认知机制。     

The role of reporting in the evaluation of rape victims

In three studies, we examined how individuals evaluate a rape victim based on whether she reports or does not report her rapist. Across all three studies, a victim who did not report the perpetrator was evaluated more negatively than a victim who did report the perpetrator. In Studies 2 and 3, symbolic concerns (the view that the victim’s actions violated shared values and disempowered herself) mediated the effect of reporting on evaluation of the victim. The effects of the victim’s relationship to the perpetrator (Study 1) and the victim’s decision to forgive the perpetrator (Study 2) were also examined. Results indicate that observers evaluate victims who do not report their perpetrators more negatively, and that this evaluation may be the result of perceptions of not reporting rape as a transgression.     

数学焦虑个体近似数量加工的神经机制:一项EEG研究

近似数量加工是对大数目物体数量在不依赖逐个数数前提下的估计。行为学研究提示高数学焦虑人群近似数量加工能力下降, 但神经机制未明。本研究探讨高数学焦虑个体近似数量加工的神经机制, 比较高低数学焦虑脑电活动的差异:(1)行为上无显著组间差异; (2)高数学焦虑组的P2p成分波幅增加; (3) δ频段ERS及β频段ERD无显著数量比例效应, 而低数学焦虑组在上述指标的数量比例效应显著。本研究为高数学焦虑人群近似数量加工能力下降提供了电生理学的证据。     

Do infants have a sense of numerosity? A p‐curve analysis of infant numerosity discrimination studies

Research demonstrating that infants discriminate between small (e.g., 1 vs. 3 dots) and large numerosities (e.g., 8 vs. 16 dots) is central to theories concerning the origins of human numerical abilities. To date, there has been no quantitative meta‐analysis of the infant numerical competency data. Here, we quantitatively synthesize the evidential value of the available literature on infant numerosity discrimination using a meta‐analytic tool called p‐curve. In p‐curve the distribution of available p‐values is analyzed to determine whether the published literature examining particular hypotheses contains evidential value. p‐curves demonstrated evidential value for the hypotheses that infants can discriminate between both small and large unimodal and cross‐modal numerosities. However, the analyses also revealed that the published data on infants’ ability to discriminate between large numerosities is less robust and statistically powered than the data on their ability to discriminate small numerosities. We argue there is a need for adequately powered replication studies to enable stronger inferences in order to use infant data to ground theories concerning the ontogenesis of numerical cognition.     

Neuronal changes in normal human aging and Alzheimer's disease

This article discusses age-related changes in brain weight, total number of cortical neurons, cortical dendrites, spine, and synapse density. The conclusion is that the present outlook is less grim than it was 30 years ago. Age-related reduction appears to be specific to brain region and cortical layer rather than a general feature. In addition, we describe a different pattern of changes that occur in Alzheimer's disease patients. This review concludes that the association cortices in particular are affected in aging and Alzheimer's disease and that the primary visual and somatosensory cortices are relatively spared.     

中国幼儿数数过程信息加工活动研究

探讨中国幼儿数数发展特点。实验1探讨3－5岁幼儿数数的终结点分布状况,结果表明,最大的密集终结点是“19”。实验2进一步考察幼儿在其数数范围内与范围外的起点进行数数的成绩,结果表明,数数范围为11－19的幼儿就开始有部分人可以在其数数范围外的起点进行数数,此表明他们开始应用了数列规则。据此可以认为,中国幼儿的数数活动同样包括联结学习与数列规则学习两种信息加工活动,但中国幼儿数列规则的学习活动在“11－19”数数过程开始。