Time reallocation in a multiresponse environment: Effects of restricting response classes

Four adult male rats were each placed for three hours daily into an apparatus that provided individual compartments for six separate location-defined responses. The available responses consisted of: (1) the opportunity to turn off room lighting, producing darkness; (2) the opportunity to view a female rat; (3) the opportunity to turn off white noise; (4) the opportunity to drink; (5) the opportunity to eat; and (6) "other," representing time in the hallway between compartments. Each subject underwent a series of conditions characterized as an A-B-A-C-A design. Manipulations consisted of the removal of a low-probability response (darkness) and of a high-probability response (escape from noise) in a counter-balanced manner across subjects. The dependent measure for all subjects was the percentage of total session time spent in each compartment. Four predictive rules concerning the redistribution of behavior after response restriction were tested, including the constant-ratio rule, equal time redistribution, the most probable alternative, and the sequential-dependency rule. The results indicate no support for any of the four predictive rules and suggest that empirical assessment of restriction effects is necessary in reinforcement studies involving temporally extended responses.     

Role of the striatal cholinergic system in the regulation of learned manipulation in rats

The experiments were performed on adult Wistar male rats trained to push with the forepaw on a fixed piston inside a narrow tube. It was found that after localized intracerebral injection of a cholinergic antagonist into the dorso-lateral (but not medial) neostriatum (i.e., the caudato-putamen) the behavioral performance requiring brief innate movements remained unchanged, but the performance requiring a prolonged pushing movement (> 50 msec) became disrupted. Microinjection of carbacholine (0.03-3 μ g/1 μ1) did not affect the performance of the acquired movements, whereas scopolamine (3 μ g/1 μ1) led to the significant decrease in pushing time. We conclude that changes in the state of the dorso-lateral neostriatal cholinergic system result only in disturbances of the sensory-controlled component of a complex instrumental movement. The 1994 Pavlovian Society Young Investigator Awardee was Nadezda Dubrovskaya, first author of this paper, which was presented at the annual meeting of the Pavlovian Society, July 3, 1994, in Prague, Czech Republic.     

Tests for stability in linear structural equation systems

Interpretations regarding the effects of exogenous and endogenous variables on endogenous variables in linear structural equation systems depend upon the convergence of a matrix power series. Convergence depends upon the eigenvalues of the structural coefficient matrix. The test for convergence developed by Jöreskog and Sörbom is shown to be only sufficient, not necessary and sufficient.     

The role of the psychologist expert witness: Provider of perspective and input

The definition and role of the expert witness is reviewed. Two conceptual systems for viewing the world, the scientific method and the adversarial system, are compared. The reconciliation and integration of these two discrepant systems are discussed in terms of input versus outcome. The rules of evidence, as well as problems of communication between the systems, are reviewed with the aim of providing expert witnesses with a better understanding of effective testimony. Finally, collaboration between the two systems is called for in order to provide guidelines for both neuropsychologists and attorneys.     

A multi-element analysis of the effect of teacher aides in an "open"-style classroom

Open classrooms with few rules, individualized instruction, and informal class organization present new problems for the application of behavior principles. The effects of three types of teacher aides on student achievement and on-task behavior were studied. Each was compared with a standard no-aide condition. Subjects were 54 third graders in two "open"-style classrooms. The three types of aide, helping adult, disciplinary adult, and helping fifth-grade aide, were compared in a multi-element design with a no-aide control. The helping-adult aide significantly affected the academic output of the class, when compared with the no-aide condition. All aide conditions produced more academic work and on-task behavior than did the standard no-aide condition.     

我国市场经济"信用"动力机制分析及其体系建构

现代社会生活的生产实践表明,分工是交换的前提,交换是分工的实现,这就是现代社会活动的全部内容和过程。在此事实基础上构建的市场经济体制,其管理理念内含着丰富的伦理意蕴[1]。本文首先分析阐述了市场经济信用体系的建立是市场经济体制内在规律的必然要求,揭示了“信用”是承诺者之间能量均衡与博弈的结果,既具有丰富的道德理性又具有明显的功利要求。文章进而通过对信用体系维护的动力因素及其与市场主体行为的相关性进行比较研究后指出:政府在参与市场经济活动中要坚持“有所为,有所不为”,应把政府置于经济利益之外,使之具有超脱于市场各成员的地位;同时,信用体系的创立和维护并不必然由政府主导,而是市场经济环境中公共合意选择的必然结果。     

精神医学中的信息系统控制原理

精神医学是临床医学的一个分枝,是高度复杂的一门科学,站在哲学的角度反思,信息系统控制科学方法渗透于精神医学的历史发展过程和临床工作的资料收集、诊断、治疗等各个环节,以及精神医学的科研工作中,还启迪着我国精神卫生事业的发展方向。     

Review

Book reviewed in this article:
David Ray Griffin, Religion and Scientific Naturalism: Overcoming the Conflicts     

现代认知心理学关于图式模型的研究

对现代认知心理学关于知识图式的研究作了系统的阐述,分析了产生式系统取向和联结主义取向的优缺点。指出：图式模型研究的整合观是近来及以后认知心理学研究的主要课题之一。     

综合性大学开设长学制高等医学教育的初步研究

我国现有的医学教育学制偏短,不利于培养高质量医学人才。综合性大学有着许多办学优势,有利于开设长学制医学教育,因此,要发挥综合性大学的优势,实行多通道办学模式,学分制和弹性学制,强化公共基础教育和人文素质教育,改善办学条件,提高管理水平,努力培养能参与国际竞争的高层次医学人才。