A pharmacological examination of the resistance-to-change hypothesis of response strength.

The effects of d-amphetamine sulfate, sodium pentobarbital, haloperidol, and cholecystokinin-octapeptide were examined within the context of Nevin's (1974, 1979) resistance-to-change hypothesis of response strength. In three experiments, rats' responding was reinforced by delivery of food under chained random-interval 30-s random-interval 30-s, multiple fixed-interval 30-s fixed-interval 120-s, or multiple random-interval 30-s random-interval 120-s schedules. Each rat received several doses of each drug and changes in response rate were measured. The resistance-to-change hypothesis predicts greater disruption of response rate relative to baseline in the initial component of the chained schedule and in the 120-s component of the multiple schedules. In the chained schedule cholecystokinin-octapeptide produced greater reductions in response rate relative to baseline in the initial component. However, no differences between components were observed with haloperidol or sodium pentobarbital, and high doses of d-amphetamine reduced response rate in the terminal component relatively more than in the initial component. In the multiple schedules either no differences were observed between components or response rate was reduced more relative to baseline in the 30-s component. The data fail to support the notion that drugs may be viewed within the same context as other response disruptors such as extinction, satiation, and the presentation of alternative reinforcement.     

3─6岁儿童层级类概念发展的实验研究

以３－６岁儿童为被试,以７个常见物体种类的图片为实验材料,按概念水平（基本类概念及上级类概念）以及选择图与目标图的感知相似程度（高、中、低）将实验材料分为四种类型,对３－６岁儿童层级类概念的发展过程进行了研究。结果表明：（１）３岁幼儿已能按基本类概念标准进行正确的种类匹配;对于上级类概念,３－５岁儿童的匹配能力尚较差,６岁基本达到掌握水平。（２）实验材料的感知相似程度对３－５岁儿童的上级类概念匹配操作有显著性影响,６岁儿童才摆脱了这种制约作用。     

3─6岁儿童层级类概念发展的实验研究

以３－６岁儿童为被试,以７个常见物体种类的图片为实验材料,按概念水平（基本类概念及上级类概念）以及选择图与目标图的感知相似程度（高、中、低）将实验材料分为四种类型,对３－６岁儿童层级类概念的发展过程进行了研究。结果表明：（１）３岁幼儿已能按基本类概念标准进行正确的种类匹配;对于上级类概念,３－５岁儿童的匹配能力尚较差,６岁基本达到掌握水平。（２）实验材料的感知相似程度对３－５岁儿童的上级类概念匹配操作有显著性影响,６岁儿童才摆脱了这种制约作用。     

字符的知觉表征及其启动

实验以英文单词,汉字和图片为材料,采用速示补笔测验测量了大脑左右半球的启动效应。结果是,如果学习与测验的字体和大小不变,则视觉启动右半球高于左半球。其他材料不产生这种效应。这表明,至少有一个分离的系统对构成启动的汉字的视觉表征进行编码,此系统在右半球表征形状特异形状特异信息更有效;对字符抽象特征的表征,两半球无显著差异,速示补笔测量的是前语义水平的知觉表征,是一种知觉（数据驱动）内隐记忆测验。     

Conditioned reinforcement by conditional discriminative stimuli.

A concurrent-chains schedule was used to examine how a delay to conditional discriminative stimuli affects conditioned reinforcement strength. Pigeons' key-peck responses in the initial link produced either of two terminal links according to independent variable-interval 30-s schedules. Each terminal link involved an identical successive conditional discrimination and was segmented into three links: a delay interval (green), a color conditional discriminative stimulus (blue or red), and a line conditional discriminative stimulus (vertical or horizontal lines). Food delivery occurred 45 s after entering the terminal link with a probability of .5, but its conditional probability (1.0 or 0) depended on the combination of the color and the line stimuli. One of the color stimuli occurred independently of further responding, 5 s after entry into the right terminal link, but it occurred 35 s after entry into the left terminal link. One of the line stimuli occurred independently of responding 40 s after entry into either terminal link, synchronized with the offset of the color stimulus. The initial-link relative response rate for the right was consistently higher in comparison with a control condition in which the color stimuli occurred 20 s after entry into either terminal link. The preference for the short delay to the color conditional discriminative stimuli suggests the possibility of conditioned reinforcement by information about the relation between the line conditional discriminative stimuli and the outcomes.     

Choice and foraging: the effects of accessibility on acceptability.

Pigeons responded in a successive-encounters choice procedure in which accessibility of the less profitable of two outcomes varied either in terms of probability of encounter or search time to encounter (keeping search time to the more profitable outcome constant). When the less profitable outcome was made more probable its acceptance became more likely. However, when search time to encounter the less profitable outcome was shortened, its acceptance became less likely. Both results are consistent with the delay-reduction hypothesis and with an optimality model developed for application to the successive-encounters choice procedure.     

Control of behavior by an establishing stimulus

Seventeen pigeons were exposed to a three-key discrete-trial procedure in which a peck on the lit center key produced food if, and only if, the left keylight was lit. The center key was illuminated by a peck on the lit right key. Of interest was whether subjects pecked the right key before or after the response-independent onset of the left keylight. Pecks on the right key after left-keylight onset suggest control of behavior by the left keylight—an establishing stimulus. In three experiments, the strength of center-keylight onset as conditioned reinforcer for a response on the right key was manipulated by altering the size of the reduction in time to food delivery correlated with its onset. Control of pigeons' key pecks by onset of the left keylight occurred on more trials per session when the center keylight was a relatively weak conditioned reinforcer and on fewer trials per session when the center keylight was a relatively strong condtioned reinforcer. Differences across conditions in the degree of control by onset of the establishing stimulus were greatest when changes in conditioned reinforcer strength occurred relatively frequently and were signaled. The results provide evidence of the function of an establishing stimulus.     

Statistical inference for false positive and false negative error rates in mastery testing

This paper describes an asymptotic inferential procedure for the estimates of the false positive and false negative error rates. Formulas and tables are described for the computations of the standard errors. A simulation study indicates that the asymptotic standard errors may be used even with samples of 25 cases as long as the Kuder-Richardson Formula 21 reliability is reasonably large. Otherwise, a large sample would be required.This work was performed pursuant to Grant No NIE-G-78-0087 with the National Institute of Education, Department of Health, Education and Welfare, Huynh Huynh, Principal Investigator. Points of view or opinions stated do not necessarily reflect NIE position or policy and no official endorsement should be inferred. The editorial assistance of Joseph C. Saunders is gratefully acknowledged.