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171.
We studied central-place foraging in rats (Rattus norvegicus) by placing food items that varied in size and weight at the ends of a 4-arm radial maze. In Experiments 1-3, rats increasingly tended to carry food to the center of the maze as the size of those items increased. Very large food items often were hoarded in the center. Rats consumed food faster on the arms than in the center, and rats traveled faster when carrying food than when not. Blocking arm entrances increased travel time between the center and the arms and decreased food carrying at every item weight except the largest. In Experiments 4-6, important conditions that influence the degree of food-carrying behavior were discovered; these were the intersection of maze arms, the presence of a conspecific, and the use of open vs. closed maze arms.  相似文献   
172.
Brief group psychotherapy as a method of treating psychological aftereffects of retirement is still in its infancy. It is therefore still possible to outline the whole field in overview. This paper examines the dynamics of aging and the relevant literature, discusses the conceptual issues involved, and describes techniques employed with this specific population. The typical cluster of complaints is portrayed, the psychological stressors associated with retirement are analyzed, and the various group-therapeutic modalities developed to counteract them are described. Furthermore, the rationale, process and characteristics of short-term group psychotherapy in the treatment of adjustment difficulties to retirement are reviewed. The clinical application of this approach, the therapist's particular roles and the therapeutic impact of this method are delineated.He would like to thank his co-therapist, Mrs. Sophie Bielawski, Reg. O.T., for her support and helpful observations and Drs. J. Regan and E. Sunday for their advice on methodolody.  相似文献   
173.
We have proposed a novel interactive procedure for performing decision analysis, called Robust Interactive Decision Analysis (RID), which permits a decision maker (DM) to voluntarily and interactively express strong (viz, sure) binary preferences for actions, partial decision functions, and full decision functions, and only imprecise probability and utility function assessments. These serve as INPUTS TO operators to prune the state probability space and decision space until an optimal choice strategy is obtained. The viability of the RID approach depends on a DM's ability to provide such information consistently and meaningfully. On a limited scale we experimentally investigate the behavioral implications of the RID method in order to ascertain its potential operational feasibility and viability. More specifically, we examine whether a DM can (1) express strong preferences between pairs of vectors of unconditional and conditional payoffs or utilities consistently; (2) provide imprecise (ordinal and interval) state probabilities that are individually as well as mutually consistent with the state probabilities imputed from the expressed strong preferences. The results show that a DM can provide strong individually and mutually consistent preference and ordinal probability information. Moreover, most individuals also appear to be able to provide interval probabilities that are individually and mutually consistent with their strong preference inputs. However, the several violations observed, our small sample size, and the limited scope of our investigation suggest that further experimentation is needed to determine whether and/or how such inputs should be elicited. Overall, the results indicate that the RID method is behaviorally viable.  相似文献   
174.
A combined multi-attribute utility and expectancy-value model has repeatedly been found to yield a worse fit to choices than to preference ratings. The present study investigated two possible explanations for this finding. First, people's belief-value structures may change in the choice task as they try to find the best alternative. Second, a difficult choice task may cause the decision maker to use simplifying heuristics. In the first of two experiments, subjective belief-value structures were measured on two occasions separated by about one week. Immediately before the second measurement, different groups of subjects performed a choice task, gave preference ratings, or performed a control task. The results did not support an interpretation of the greater difficulty of predicting choices in terms of changes in belief-value structures. However, the notion of simplifying heuristics received support by the finding that adopting simpler versions of the original model improved the predictions of the choices. In the second experiment, beliefs were measured immediately before or after each of a series of choices or preference ratings. The results indicated that although temporary changes in beliefs may occur, they can hardly provide a full account of the differential predictability of preferences and choices.  相似文献   
175.
In this study, we describe the process of transforming neuron polarization values that meet the assumptions of ratio data into ordinal data. This is a crisp-to-fuzzy set transformation. A computerized simulation of the application of this process is discussed and nonparametric methods of analyzing fuzzy-set data are presented.  相似文献   
176.
A sample of physician-referred chronic insomniacs was randomly allocated to either progressive relaxation, stimulus control, paradoxical intention, placebo or no treatment conditions. Treatment process and outcome were investigated in terms of mean and standard deviation (night to night variability) measures of sleep pattern and sleep quality. Only active treatments were associated with significant improvement, but the nature of treatment gains varied. In particular, stimulus control improved sleep pattern, whereas relaxation affected perception of sleep quality. All improvements were maintained at 17 month follow-up. Results are discussed with reference to previous research and guidelines are given for clinical practice.  相似文献   
177.
178.
The purpose of this work is to explore the phenomenon of negativism and the analyst's response to it during the course of analytic work with a patient in whom negativism is a central behavioral pattern. Melville's short story, "Bartleby the Scrivener," describing in telling detail the response of a sympathetic lawyer to profound and pervasive negativism in his legal scribe, is discussed as a literary analogy to the analyst-analysand dyad. Aspects of the concept of negativism within psychoanalysis are discussed. The potential usefulness of understanding certain unexpected countertransference responses to pervasive negativism is explored, as this is a relatively neglected area of psychoanalytic technique. A case is presented describing the analysis of a patient whose character, like Bartleby's, is a mixture of profound negativism along with schizoid, obsessional, and masochistic elements.  相似文献   
179.
J Duffy  T J Coates 《Adolescence》1989,24(93):29-37
Pregnant adolescents who smoke present a double obstetrical risk. Not only is the adolescent mother at risk from the biological, social, educational, and economic factors associated with childbearing at a young age, she and her developing infant also risk the complications associated with maternal smoking. This paper describes a psychosocial intervention designed to reduce smoking in a group of pregnant adolescents. Five modules are presented. Each is designed to: (1) heighten awareness of the issue, (2) provide motivational messages, (3) enhance the adolescent's social skills, and (4) teach specific smoking-cessation skills.  相似文献   
180.
Microgenesis as traced by the transient paired-forms paradigm   总被引:2,自引:0,他引:2  
Two successive, spatially overlapping human faces were exposed for recognition with SOAs ranging from 20 to 160 msec. The subjects effectively perceived one face, which at short SOAs mostly resembled the first stimulus and with increasing SOAs gradually shifted towards the appearance of the second, dimmer stimulus. These results replicated those from the study by Calis, et al, and extended them to the experimental conditions of controlled simultaneity of each of the two temporally separate, extremely brief stimuli and to the conditions of personally unfamiliar stimulus-subjects. In the second experiment we employed a direct measurement of the microgenetic focus in real time by using a procedure by which the subjects' judgments about the relative temporal order of the critical visual stimulus and an auditory click were recorded. Via this procedure it was shown that one of the effects of the first visual stimulus is to speed up the microgenetic process for the second stimulus which then appears subjectively earlier as compared to the single-stimulus control.  相似文献   
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