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971.
972.
Summary In this paper some implications of the pulse generator model of time perception have been tested. In the case of serial (re)production of an interval a lengthening effect occurs. Generally, this phenomenon is explained by assuming that the time-keeper is driven by the state of general physiological activation which decreases in the course of the task. An experiment was carried out in which EEG activity was recorded during the time estimation process. It appeared that a lengthening effect occurred, but there was no correlation between the reproduction times and the means of the EEG spectra, however. In a second experiment two series of time estimations were compared as a function of administering a placebo and methamphetamine. In the latter case the model predicts that no lengthening will occur since arousal (at least for a short period of time) is kept at a high and constant level. In fact, no differences between the regressions of the time estimation curves before and after drug administration have been found, so that the predictions of the model as regards the origin of lengthening could not be supported. It is suggested that the nature of the effect should be studied within the framework of the cognitive theory of time experience which offers various starting points in this respect.  相似文献   
973.
Conclusion I have so far ignored Earman's Section IV in which spatiotemporal coincidence is discussed. The answer will be clear from the preceding: the exact definitions and principles of the exact theories we have displayed are to be discussed with reference to the special and not the general theory of relativity. But moreover, Earman's transition from (C) to (1) assumes what we do not grant: that events are causally connectible exactly if the points in the mathematical space-time at which they are located are linked by a causal curve.This captures in a nutshell my own conclusions. The first is that the causal theory, after its success vis-à-vis the STR, must now provide a detailed analysis of spatiotemporal concepts in the GTR. The second is that the points raised by Earman do not provide substantive reasons for doubting the adequacy of the causal theory to this task, because Earman insists in his extrapolations on a much closer relation between the empirical structure of events and the mathematical structures that model it than ought to be assumed.I wish to acknowledge gratefully my debt to Dr. A. Grünbaum, University of Pittsburgh, to Dr. C. Glymour, Princeton University, and to the support of the John Simon Guggenheim Memorial Foundation.  相似文献   
974.
This article provides evidence for an extension of structural information theory, a theory which describes perceptual organization formally, into a more general theory of representation that takes the role of organizations obtained earlier into account. In eight experiments, subjects study series of colored dots. Each series contained 6-8 dots of different colors, and viewing time was between 400 ms and 60 s. In several experimental procedures, subjects recalled the series presented. The experiments systematically varied the economy of the organizations of the series as described by structural information theory as well as a number of aspects of the context in which the series were presented, like order of presentation of a series, order between the series, viewing span, viewing time, and recall procedure. Recall was influenced both by the economy as well as by the context. It is shown how the context influences the relative strength of the most economical organization as compared with rival, local organizations. A structured network model is presented that accounts for the influence of both the economy and the context.  相似文献   
975.
This study investigated whether external locus of control, as measured with the Rotter Internal-External Locus of Control Scale, is a specific feature of agoraphobia or whether it characterizes neurosis in general. Forty agoraphobic patients, 81 nonagoraphobic neurotic controls, and 49 normal controls completed the Dutch version of the Rotter Internal-External Locus of Control Scale. Agoraphobic patients were found to have a more external orientation as compared to the normal controls, but as a group, they could not be identified as being different from neurotic controls.This study was supported in part by a grant from the Dutch Organization for Fundamental Research (ZWO/Psychon 560-268-001).  相似文献   
976.
977.
In order to investigate the relationship between the extent to which clinical fears are prepared and clinically relevant characteristics of these fears (i.e. severity, age of onset and treatment outcome). the records of 63 obsessional and phobic patients were examined. Four independent raters scored the usable records (N = 55) on preparedness. The preparedness scores were combined and related to objective indices of severity (patients' scores on the Fear Survey Schedule, the Zung Depression Scale and the Maudsley Obsessional-Compulsive Inventory, as well as the treatment duration), onset ages and treatment outcomes (pre-treatment minus post-treatment MOCI scores, for a subsample of obsessional patients only). In contrast to earlier studies, it was found that product-moment correlations among preparedness ratings were relatively low and that prepared fears did not make up a majority in the sample. Indices of severity either did not correlate at all or correlated negatively with preparedness ratings. The positive correlation between preparedness and onset ages reached borderline significance. Evidence suggestive of a resistance to treatment of prepared fears was obtained.  相似文献   
978.
The relationship between headaches and mood   总被引:1,自引:0,他引:1  
  相似文献   
979.
In this study, we hypothesized that securely attached infants would in kindergarten perform better on an intelligence test than anxiously attached children. No difference was expected between children of working mothers (working more than 15 hours outside the home) and children of full-time homemakers. Mother-child pairs (N = 77; average age of child was 24 months) were observed during the Strange Situation procedure; three years later, 65 children completed the Leiden Diagnostic Test for measuring intelligence level. Results showed that the securely attached reference group attained the highest IQ. The working status of the mother did not appear to make a difference.  相似文献   
980.
Two kinds of measures of multivariate association, based on Wilks' and the Bartlett-Nanda-Pillai trace criterionV, respectively, are compared in terms of properties of the univariateR 2 which they generalize. A unified set of derivations of the properties is provided which are self-contained and not restricted to decompositions in canonical variates. One conclusion is that asymmetric index based on allows generalization of the multiplicative decomposition ofR 2 in terms of squared partial correlations, but not the additive decomposition in terms of squared semipartial correlations, while the reverse is true for anasymmetric index based onV.We are indebted to Jos M. F. ten Berge for some fruitful discussions.  相似文献   
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