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In male Betta splendens, aggressive behavior is drastically attenuated following telencephalon ablation. Because instrumental training and Pavlovian conditioning experiments with intact fish have suggested that associative factors may play an important role in the performance of agonistic behaviors, the effect of ablation on instrumental learning and Pavlovian conditioning was studied. In Experiment 1, ablation had no effect on the learning of the instrumental tunnel-swimming response reinforced by mirror presentation (i.e., viewing a conspecific), although the mirror presentations in yoked-control groups elicited fewer responses in ablates than in normal and sham-operated control fish. Yoked controls further established that instrumental responding was maintained by the reinforcement contingency and was not merely the result of increased motor activity. Experiment 2 studied Pavlovian conditioning of the components of the agonistic display. Unconditioned fin erection, gill erection, and tail beating (i.e., unconditioned responses, URs) to the mirror US all were less frequent in ablates than in normals or shams. Of these, only gill cover erection showed evidence of true conditioning (i.e., conditioned responses; CRs) in which responses to the conditioned stimulus (CS) are due to the pairings of CS and US (unconditioned stimulus). However, ablates suffered no impairment of conditioned gill erections. Ablates performed fewer fin erections to the CS; however, fin erection responses were not due to CS-US pairings but were attributable to pseudoconditioning. These results are related to hypotheses postulating the involvement of learning mechanisms in ablation-produced deficits and normal aggressive behavior.  相似文献   
915.
This paper examines the relationship between response impulse and timing error in 200 msec discrete timing responses over a range of movement velocities and system masses. The results from two experiments showed that variable timing error decreased as both movement velocity and the mass of the system to be moved increased. The variability of force proportional to force (measured either as impulse or peak force) decreased curvilinearly as force out-put increased. The correlations between each of these parameters and variable timing errors, calculated on a group mean basis, ranged between.91 and.95. The ability to predict the movement time outcome of each individual trial from impulse-related parameters was considerably reduced, although the relationship between the various kinematic and kinetic parameters did strengthen as the movement velocity approached maximum. Collectively, the findings show the size of impulse is related to movement timing error, although it is premature argue that impulse variability is a causal agent of timing error.  相似文献   
916.
Many questions are currently being raised, by women especially, regarding the religious, social, and psychological effects of the emphasis on God as father in Western religion. Viewed in the light of key insights from developmental psychoanalysis, patriarchal monotheism does indeed seem to confront us with a dilemma. However, a resolution of this dilemma does not appear to lie in a move toward androgyny or matriarchy. Evaluated from the point of view of its overall capacity to mediate a meaningful, unified, personal religious reality to both sexes, monotheistic father religion is still the preferable ultimate symbolic configuration.  相似文献   
917.
The possibility of isolating personality types using 16 PF profiles was studied by utilizing a Q-type factor analytic procedure. Four modal profiles, characteristic of major clusters of subjects, were derived and cross validated. These four major types successfully classified approximately 2/3 of the 16 PF protocols (n = 1037), and classified similar proportions of previously published profiles. Variation of classification rates as a function of race and sex was described, and strategies for utilizing the profiles for research and interpretive purposes were outlined.  相似文献   
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919.
It is generally agreed that concept learning involves the abstraction of some general representation or schema. Just what is abstracted, however, and how it is used in the classification of sets of stimuli in the natural world or in the laboratory, remain outstanding questions. In this paper a hypothesis involving contingency abstraction is described as a possible solution to these questions. An experiment which manipulated measured contingency in a concept-learning task, and which offered empirical support for the hypothesis, is reported. The advantages of a contingency-abstraction theory of concept learning are briefly discussed.  相似文献   
920.
Recent research has shown that academic choice and achievement may be partly a function of the student's standing on the field-dependence-independence cognitive-style dimension. The results of two longitudinal studies suggest that information about field dependence-independence may be of value for student guidance in the medical setting. The first, a study of college undergraduates who early expressed an interest in medicine, showed that these cognitive styles play a discernible role in determining who will eventually enter medical school. The second, a study of medical students, showed that field-dependent and field-independent students subsequently tend to choose different medical specialties. These results are consistent with cognitive-style theory, which proposes that field-independent people will choose vocations that require cognitive restructuring skills, whereas field-dependent people will choose vocations that require greater social-interpersonal involvement.  相似文献   
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