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31.
Behavioral contrast in fixed-interval components: effects of extinction-component duration. 下载免费PDF全文
J C de Rose 《Journal of the experimental analysis of behavior》1986,45(2):175-188
Seven albino rats were exposed to a multiple schedule of reinforcement in which the two components (fixed interval and extinction) alternated such that a presentation of the extinction component followed each fixed-interval reinforcement. In baseline sessions, the duration of the extinction component was constant and always one-third of the fixed-interval value. Probe sessions contained a probe segment in which the duration of the extinction component was increased; the response rate in fixed-interval components during the probe segment was compared with the response rate in the segments preceding and following the probe. The effect of increasing the duration of the extinction component was studied under three values of fixed interval: 30 s, 120 s, and 18 s, in three successive conditions. Response rate within fixed intervals was a direct function of duration of the extinction component. Pausing at the beginning of the fixed interval decreased as extinction duration increased. These effects were larger and more consistent for the shorter fixed-interval values (18 s and 30 s). These results indicate a functional relation between relative component duration and responding. For the component providing more frequent reinforcement, this could be stated as an inverse relationship between relative component duration and response rate. This relation is similar to findings regarding the ratio of trial and intertrial duration in Pavlovian conditioning procedures, and suggests that behavioral contrast may be related to Pavlovian contingencies underlying the multiple schedule. 相似文献
32.
In some recent papers, the authors and Peter Gärdenfors have defined and studied two different kinds of formal operation, conceived as possible representations of the intuitive process of contracting a theory to eliminate a proposition. These are partial meet contraction (including as limiting cases full meet contraction and maxichoice contraction) and safe contraction. It is known, via the representation theorem for the former, that every safe contraction operation over a theory is a partial meet contraction over that theory. The purpose of the present paper is to study the relationship more finely, by seeking an explicit map between the component orderings involved in each of the two kinds of contraction. It is shown that at least in the finite case a suitable map exists, with the consequence that the relational, transitively relational, and antisymmetrically relational partial meet contraction functions form identifiable subclasses of the safe contraction functions, over any theory finite modulo logical equivalence. In the process of constructing the map, as the composition of four simple transformations, mediating notions of bottom and top contraction are introduced. The study of the infinite case remains open. 相似文献
33.
Two different concepts of distinguishability are often mixed up in attempts to derive in quantum mechanics the (anti)symmetry of the wave function from indistinguishability of identical particles. Some of these attempts are analyzed and shown to be defective. It is argued that, although identical particles should be considered as observationally indistinguishable in (anti)symmetric states, they may be considered to be conceptually distinguishable. These two notions of (in)distinguishability have quite different physical origins, the former one being related to observations while the latter has to do with the preparation of the system. 相似文献
34.
While emotions are usually treated as internal states, it is possible to view them as social relationships. From this perspective, the different emotions are not primarily understood in terms of facial expression, physiological pattern, hedonic tone, or level of arousal, but as different transformations of the relationship between person and other. To demonstrate the value of this approach, judgments of the similarity between different emotions were submitted to multidimensional scaling. It is shown that the resulting dimensions describe different aspects of the relation between self and other. These dimensions provide us with a taxonomy of emotions that makes some important distinctions between closely related emotions and leads to some interesting predictions about personality differences.The authors would like to thank David Stevens for his assistance with the statistical analysis, Eric de Rivera for drafting the three-dimensional figures, and James D. Laird and Shula Sommers for their helpful commentary. 相似文献
35.
Disturbances in exploratory behavior and functional recovery in the Y and radial mazes following dopamine depletion of the lateral septum 总被引:1,自引:0,他引:1
The effects of 6-hydroxydopamine (6-OHDA) injected into the lateral septum in rats were investigated for spontaneous alternation behavior in a Y maze and for spatially oriented behavior in an 8-arm radial maze. The performance of the animals in these tests was assessed under two physiological states, food-satiated and food-deprived. The selective depletion of septal dopaminergic concentrations leads to behavioral disturbances in both the Y and the radial mazes. These deficits disappeared when the animals with 6-OHDA lesions were food-deprived. These results confirm other studies from our laboratory and support two conclusions. First, lesions of dopaminergic neurons lead to behavioral impairments which resemble those found after the total lesion of the structure they innervate. Second, these behavioral impairments are responsive to therapeutic treatments, manipulations of the internal or external environment, or the level of arousal, since under certain conditions a recovery of function can occur in the absence of dopaminergic neurons. These two points provide additional support for a nonspecific role for the dopaminergic neurons originating in the ventral tegmental area. These neurons could have a permissive role in the functioning of the forebrain structures they innervate. 相似文献
36.
Distinctions between social support concepts,measures, and models 总被引:24,自引:0,他引:24
Manuel Barrera Jr. 《American journal of community psychology》1986,14(4):413-445
37.
A general structural equation model with dichotomous,ordered categorical,and continuous latent variable indicators 总被引:21,自引:0,他引:21
Bengt Muthén 《Psychometrika》1984,49(1):115-132
A structural equation model is proposed with a generalized measurement part, allowing for dichotomous and ordered categorical variables (indicators) in addition to continuous ones. A computationally feasible three-stage estimator is proposed for any combination of observed variable types. This approach provides large-sample chi-square tests of fit and standard errors of estimates for situations not previously covered. Two multiple-indicator modeling examples are given. One is a simultaneous analysis of two groups with a structural equation model underlying skewed Likert variables. The second is a longitudinal model with a structural model for multivariate probit regressions.This research was supported by Grant No. 81-IJ-CX-0015 from the National Institute of Justice, by Grant No. DA 01070 from the U.S. Public Health Service, and by Grant No. SES-8312583 from the National Science Foundation. I thank Julie Honig for drawing the figures. Requests for reprints should be sent to Bengt Muthén, Graduate School of Education, University of California, Los Angeles, California 90024. 相似文献
38.
Animal Cognition - The alarm calls of nonhuman primates are occasionally cited as functionally equivalent to lexical word meaning in human language. Recently, however, it has become increasingly... 相似文献
39.
The aim of this study is to gain empirical knowledge about how the Bible functions in the context of Protestant Christian primary schools in the Netherlands. It presents the results of an empirical explorative and qualitative study on the perceptions of teachers and school administrators (directors and internal supervisors) on the goals of Bible use in Protestant primary education, as well as the roles of teachers and pupils, and how these can be understood in terms of religious pedagogical models and theories. Five small focus group interviews with teachers and six interviews with school administrators revealed a variety of goals teachers hold regarding Bible use in education and a variety of divisions of teacher–learner roles in this regard. The findings also show some particular characteristics when compared with secondary schools. 相似文献
40.
Paul G. Bain Renata Bongiorno Kellie Tinson Alanna Heanue Ángel Gómez Yanjun Guan Nadezhda Lebedeva Emiko Kashima Roberto González Sylvia Xiaohua Chen Sheyla Blumen Yoshihisa Kashima 《Asian Journal of Social Psychology》2023,26(4):504-535
People hold different perspectives about how they think the world is changing or should change. We examined five of these “worldviews” about change: Progress, Golden Age, Endless Cycle, Maintenance, and Balance. In Studies 1–4 (total N = 2733) we established reliable measures of each change worldview, and showed how these help explain when people will support or oppose social change in contexts spanning sustainability, technological innovations, and political elections. In mapping out these relationships we identify how the importance of different change worldviews varies across contexts, with Balance most critical for understanding support for sustainability, Progress/Golden Age important for understanding responses to innovations, and Golden Age uniquely important for preferring Trump/Republicans in the 2016 US election. These relationships were independent of prominent individual differences (e.g., values, political orientation for elections) or context-specific factors (e.g., self-reported innovativeness for responses to innovations). Study 5 (N = 2140) examined generalizability in 10 countries/regions spanning five continents, establishing that these worldviews exhibited metric invariance, but with country/region differences in how change worldviews were related to support for sustainability. These findings show that change worldviews can act as a general “lens” people use to help determine whether to support or oppose social change. 相似文献