Oral self-administration of pentobarbital by rhesus monkeys: maintenance of behavior by different concurrently available volumes of drug solution.

For 4 rhesus monkeys, mouth-contact responses with either of two brass spouts were reinforced according to fixed-ratio schedules by 0.65-mL liquid deliveries during daily 3-hr sessions. Three experiments were conducted. In each experiment, independent fixed-ratio schedules were concurrently in effect at the two spouts. Following completion of each fixed ratio on a spout, a specified number of liquid deliveries were available from that spout under a continuous-reinforcement schedule. The number of such deliveries available at each spout was manipulated independently. In Experiment 1, a 1-mg/mL pentobarbital solution was simultaneously available with water (the drug vehicle) under concurrent fixed-ratio schedules of 32 responses for 3 subjects and 64 responses for the remaining subject. The number (N) of liquid deliveries that were available after completion of each fixed ratio was varied in the following order: 8, 4, 2, 1, and 8 (retest). For each subject at each condition, drug maintained more responding than water. The number of drug deliveries obtained per session was directly related to the amount of drug available per fixed ratio (i.e., to N), whereas the number of fixed ratios completed per session generally was inversely related to the value of N. In Experiment 2, fixed-ratio size was the same for each subject as in Experiment 1, but deliveries of a 1-mg/mL pentobarbital solution were available at both spouts. The number of drug deliveries available under one fixed-ratio schedule (Ns, the "standard" reinforcer amount) was held at eight, and the number of drug deliveries available under the second schedule (Nc, the "comparison" reinforcer amount) was changed across blocks of six sessions of stable responding in the following order: 1, 2, 4, 8, 4, 2, and 1. The identical series of comparison reinforcer amounts (Nc) was then tested twice more, but with the standard reinforcer (Ns) held first at four and then at two deliveries. Across the three choice series, reinforcing effects were directly related to reinforcer magnitude. In Experiment 3, deliveries of a 1-mg/mL pentobarbital solution again were available at both spouts. However, the two reinforcer amounts were held constant at N = 8 deliveries under one schedule and N = 4 deliveries under the second schedule, and fixed-ratio size was systematically varied. Across the range of fixed-ratio sizes from low to high, the degree to which behavior was better maintained by the larger of the two drug quantities was an inverted U-shaped function of fixed-ratio size.(ABSTRACT TRUNCATED AT 400 WORDS)     

Alternative test criteria in covariance structure analysis: A unified approach

In the context of covariance structure analysis, a unified approach to the asymptotic theory of alternative test criteria for testing parametric restrictions is provided. The discussion develops within a general framework that distinguishes whether or not the fitting function is asymptotically optimal, and allows the null and alternative hypothesis to be only approximations of the true model. Also, the equivalent of the information matrix, and the asymptotic covariance matrix of the vector of summary statistics, are allowed to be singular. When the fitting function is not asymptotically optimal, test statistics which have asymptotically a chi-square distribution are developed as a natural generalization of more classical ones. Issues relevant for power analysis, and the asymptotic theory of a testing related statistic, are also investigated.This research has been supported by the U.S.-Spanish Joint Committee for Cultural and Educational Cooperation, grant number V-B.854020. The author wishes to express his gratitude to P. M. Bentler who provided very helpful suggestions and research facilities—with an stimulating working environment—at the University of California, Los Angeles, where this work was undertaken. Thanks are also due to W. E. Saris who provided very valuable comments to earlier versions of this paper. Finally, it has also to be acknowledged the editor's and reviewers suggestions which led to substantial improvements of this article.     

Human observing: maintained by negative informative stimuli only if correlated with improvement in response efficiency.

Two experiments investigated the effect of observing responses that enabled college students to emit more efficient distributions of reinforced responses. In Experiment 1, the gains of response efficiency enabled by observing were minimized through use of identical low-effort response requirements in two alternating variable-interval schedules. These comprised a mixed schedule of reinforcement; they differed in the number of money-backed points per reinforcer. In each of three choices between two stimuli that varied in their correlation with the variable-interval schedules, the results showed that subjects preferred stimuli that were correlated with the larger average amount of reinforcement. This is consistent with a conditioned-reinforcement hypothesis. Negative informative stimuli--that is, stimuli correlated with the smaller of two rewards--did not maintain as much observing as stimuli that were uncorrelated with amount of reward. In Experiment 2, savings in effort made possible by producing S- were varied within subjects by alternately removing and reinstating the response-reinforcement contingency in a mixed variable-interval/extinction schedule of reinforcement. Preference for an uncorrelated stimulus compared to a negative informative stimulus (S-) decreased for each of six subjects, and usually reversed when observing permitted a more efficient temporal distribution of the responses required for reinforcement; in this case, the responses were pulls on a relatively high-effort plunger. When observing the S- could not improve response efficiency, subjects again chose the control stimulus. All of these results were inconsistent with the uncertainty-reduction hypothesis.     

Choice: A local analysis

Analyses of free-operant choice usually employ one of two general procedures: the simple concurrent procedure (i.e., a concurrent variable-interval variable-interval schedule) or the concurrent-chains procedure (i.e., concurrently available initial links, each leading to an exclusively available terminal link). Theories about choice usually focus on only one of the two procedures. For example, maximization theories, which assert that behavior is distributed between two alternatives in such a way that overall rate of reinforcement is maximized, have been applied only to the simple concurrent procedure. In the present paper, a form of the pairing hypothesis (according to which pairings between one stimulus and another affect the value of the first, and pairings between responses and reinforcers affect the value of the former) is developed in a way that allows it to make qualitative predictions with regard to choice in a variety of simple concurrent and concurrent-chains procedures. The predictions include matching on concurrent variable-interval variable-interval schedules, preference reversal in the self-control paradigm, and preference for tandem over chained terminal links.     

推理结论正确性判定标准再探

本文试图探求人们在进行三段论推理加工时是否存在形式和内容双重标准。由既掌握形式逻辑推理规则又知道构成推理题的两个前提是否正确的被试所进行的推理结果支持下述观点：人们在进行三段论推理过程中,在判定推理结论的正误时,存在着与试题结构相应的两种内在的判定标准,即“形式标准”和“内容标准”。     

青少年心理健康素质的概念和结构初探

青少年心理健康素质是健康心理学中具有开创性和探索性的研究领域,因此涉及若干理论问题需要探讨。其中青少年心理健康素质的基本概念和基本结构是该研究领域首先应探讨的基本理论问题。     

智力开发的基本理念与实践

以高度分化的g因素研究为理论基础,智力开发活动形成了神经潜能开发、心理管理与反省经验开发、专家技能开发、多元智力开发、社会分布式认知开发、知识表征重组开发、环境重组开发等智力要素开发理念以及一些代表性的实践。随着对智力结构的整合研究的出现和不断深入,智力开发理念和模式将由分化的要素开发向整合开发转变,以智力与其他心理结构、智力与内部世界和外部世界系统关系为基础的智力开发将是理论和实践研究的重点内容     

中学生师生关系的结构、类型及其发展特点

选取319名初一至高三学生作为被试,主要采用问卷法,考察中学生师生关系的结构、类型及其发展特点。结果表明：（1）师生关系结构具有冲突性、依恋性、亲密性和回避性四个维度;（2）师生关系类型包括矛盾冲突型、亲密和谐型和疏远平淡型三种类型;（3）师生关系各维度不存在显著性别差异,但存在显著年级差异,师生关系质量随年级升高呈波浪式下降趋势,初一学生的师生关系最好,初二和高二学生的师生关系最不理想;（4）师生关系各类型的人数比例存在显著年级差异。     

信息表征形式对解决贝叶斯推理问题的影响

通过三个实验分别考察问题形式（一步问题,两步问题）、信息结构（分割结构,未分割结构）和辅助图形表征（条形图、饼图、结构图）对解决贝叶斯推理问题的影响。研究结果表明：(1)一步问题形式有时优于两步问题形式;(2)频率格式提问有时优于几率格式提问;(3)分割的信息结构明显优于未分割的信息结构;(4)与条形图和饼图形式的图形辅助表征相比,结构图形式的图形辅助表征显著提高了被试解决贝叶斯推理问题的成绩。