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121.
Duration-reduction of avoidance sessions as negative reinforcement   总被引:6,自引:6,他引:0       下载免费PDF全文
Five rats were exposed to a shock-postponement procedure in which responses on each of two levers initially had equivalent effects. After an initial training sequence that ensured at least some responding on each lever, an additional consequence was made conjointly operative on the previously less-preferred lever for each animal. Each response on this lever continued to postpone shock, but also reduced the session duration by one minute. The conjoint contingencies were operative until, through session-shortening responses and the passage of time, the session was scheduled to end in two minutes; during the final two minutes the session-shortening contingency was disabled while the shock-postponement contingency continued to be operative on both levers. When responding shifted to a predominance on the session-shortening lever, the conjoint contingency was shifted to the other lever; for four of the five rats this reversal was followed by two additional reversals. Two of the rats' responding showed clear, strong, and unambiguous sensitivity to the session-shortening contingency. The responding of two others was also systematically controlled by that contingency, but the effects were less clearcut. The fifth animal showed an initial shift when session-shortening was introduced, but its subsequent behavior proved insensitive to reversals of procedure. The results clearly indicate a sensitivity of behavior to events on a time scale quite distinct from that of immediate consequences. They also support an interpretation of avoidance sessions, considered in their entirety, as events whose contingent relationship to behavior can affect that behavior—even in the absence of stimuli that delineate those relationships. Finally, these results support an interpretation of aversively based conditioning within a broader context, analogous to the “open versus closed economy” interpretation of appetitively controlled behavior.  相似文献   
122.
三、敬畏 敬畏是一种宗教美德,《古兰经》用它来确定人与人、人与造物主之间的关系。“敬畏”一词及其派生词大都出现在《古兰经》中有关道德和社会主张的经文中。所谓“敬畏”就是要人类谨防那些使真主恼怒和损人害己的行为。因为“敬畏”一词本意为保护自己。人之所以保护自己,是因有可惧怕的东西存在。安拉是最值得惧怕的,所以因安拉而保护自己是特别重要的。既然惧怕,就  相似文献   
123.
七、公正 伊斯兰教的理想之一就是责成其信徒要丢掉一切与自身利害有关的考虑,主持人间公道。安拉说:“信教的人们!你们应主持公正,应为安拉而作见证,即使不利于自身,或自己的父母和亲属。不论被见证者是富人或贫人,那安拉是最宜于对付他们的。你们不要徇私,以免偏离公正;如果你们歪曲事实,或拒绝作证,那安拉对你们的作为将是一清二楚。”(4:135)  相似文献   
124.
125.
Choice, changeover, and travel: A quantitative model   总被引:4,自引:4,他引:0       下载免费PDF全文
Six pigeons were trained on concurrent variable-interval schedules in which responding on fixed-interval schedules was required to give access to the alternate schedule. Responding on the concurrent schedules was not allowed, after changing over had commenced, until the changeover schedule had been completed. In Parts 1 to 3 of the experiment, the changeover fixed-interval schedules were equal and were 0 s, 10 s, and 20 s, respectively. In each part, the relative frequency of reinforcement obtained on the concurrent schedules was varied over at least five conditions. In Part 4, the concurrent schedules were equal, and one changeover fixed-interval schedule was twice the other. Under these conditions, the absolute sizes of the changeover schedules were varied. Increasing the changeover requirement from 0 s to 10 s (Parts 1 and 2) resulted in increases in the sensitivity of behavior allocation to reinforcers obtained, but no further increase was obtained when the changeover schedules were increased to 20 s (Part 3). In Part 4, performance was biased towards the concurrent schedule that took less time to enter. These results are consistent with a subtractive punishment model of travel in which the degree of punishment is measured by the number of reinforcers apparently lost from a schedule when the subject changes to that schedule. Absolute times spent on the main keys could be accurately described by a previous model of changeover performance.  相似文献   
126.
Five pigeons were trained on concurrent variable-interval schedules arranged on two keys. In Part 1 of the experiment, the subjects responded under no constraints, and the ratios of reinforcers obtainable were varied over five levels. In Part 2, the conditions of the experiment were changed such that the time spent responding on the left key before a subsequent changeover to the right key determined the minimum time that must be spent responding on the right key before a changeover to the left key could occur. When the left key provided a higher reinforcer rate than the right key, this procedure ensured that the time allocated to the two keys was approximately equal. The data showed that such a time-allocation constraint only marginally constrained response allocation. In Part 3, the numbers of responses emitted on the left key before a changeover to the right key determined the minimum number of responses that had to be emitted on the right key before a changeover to the left key could occur. This response constraint completely constrained time allocation. These data are consistent with the view that response allocation is a fundamental process (and time allocation a derivative process), or that response and time allocation are independently controlled, in concurrent-schedule performance.  相似文献   
127.
Critics have questioned the value of human operant conditioning experiments in the study of fundamental processes of reinforcement. Contradictory results from human and animal experiments have been attributed to the complex social and verbal history of the human subject. On these grounds, it has been contended that procedures that mimic those conventionally used with animal subjects represent a "poor analytic preparation" for the explication of reinforcement principles. In defending the use of conventional operant methods for human research, we make three points: (a) Historical variables play a critical role in research on processes of reinforcement, regardless of whether the subjects are humans or animals. (b) Techniques are available for detecting, analyzing, and counteracting such historical and extra-experimental influences; these include long-term observations, steady state designs, and, when variables are not amenable to direct control (e.g., age, gender, species), selection of subjects with common characteristics. (c) Other forms of evidence that might be used to validate conditioning principles-applied behavior analysis and behavioristic interpretation-have inherent limitations and cannot substitute for experimental analysis. We conclude that human operant conditioning experiments are essential for the analysis of the reinforcement process at the human level, but caution that their value depends on the extent to which the traditional methods of the experimental analysis of behavior are properly applied.  相似文献   
128.
一般地说,认知风格可以被理解为个人感知、组织以及评价信息的独特方式。然而,除此之外,本文要论及的四项系列研究运用了两种量表,它们反映了对认知风格的不同而独特的解释。一种量表是迈尔斯—布立格斯类型量表(Myers—Briggs Type lndlcator),这是一套著名的量表,它是以荣格(Jungian)的人格理  相似文献   
129.
朱马达·阿黑赖第一讲赞美安拉——造化所有万物的主,开天辟地的主,布施给养的主。巢中群鸟赞他清净,各路王侯颂他崇高。赞主清净,他是崇高普施的主,其拥有之财富不因博施而罄绝。我赞美安拉清净玄高,赞主会持续给  相似文献   
130.
逻辑的范围     
人们在作出陈述时,可能提供论据以支持它们,也可能不这样。一个被论据支持的陈述是一个论证的结论,而逻辑则提供对论证进行分析的工具。逻辑分析所涉及的是结论和支持它的论据之间的关系。人们思考时,作出推理,这些推理可以转变为论证,而逻辑工具这时就应用于这些得出的论证之上。这样,就可以检验产生这些论证的推理。逻辑研究论证与推理。它的主要目的之一是为区别逻辑上正确的与不正确的论证与推理提供方法。  相似文献   
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