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Escape behavior under different fixed ratios and shock intensities   总被引:1,自引:1,他引:0       下载免费PDF全文
The effects of ratio length and shock intensity on bar pressing were examined in three rats in two escape-from-shock experiments. In Experiment I, shock intensity was held constant while the schedule was varied from FR 1 to FR 20. The latency of the first escape response increased with FR length while the escape rate, computed as over-all rate in shock minus latency of the first response, decreased at FR 20. In Experiment II, the schedule was held constant at FR 5 while shock intensity was manipulated. Latency decreased as intensity increased, while escape rate increased with intensity, passing through a maximum for two subjects. Responses occurring during the last 100 sec of the 2-min escape period decreased as the FR increased for all subjects, and decreased as shock intensity increased for two subjects.  相似文献   
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In this paper a case is used to demonstrate how ethical analysis enables health care professionals, patients and family members to make treatment decisions which ensure that medical technologies are used in the overall best interests of the patient. The claim is made and defended that ethical analysis can secure four beneficial outcomes when medical technologies are employed: (1) not allowing any medical technologies to be employed until the appropriate decision makers are identified and consulted; (2) insisting that medical technologies be employed not merely to promote the medical interests of the patient but rather on the basis of their ability to contribute to the overall well-being of the patient; (3) challenging caregivers to reflect on the dynamic interplay between their conscious and unconscious values and consequent determinations of what is in the patient's best interests; and (4) providing a justification for selected interventions which makes possible rational dialogue between caregivers espousing different viewpoints about treatment options.  相似文献   
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Thirty-eight male college students, classified as either Type A or Type B based on their Jenkins Activity Survey (JAS-T) scores, competed in a reaction time task that allowed them to administer shocks to an increasingly provocative fictitious opponent. Salivary testosterone and cortisol were measured both prior to and after the task. Aggression was defined as the level of shock the subject was willing to set for the opponent. The results of this study indicate that a relationship exists between endogenous testosterone levels in men and direct physical aggression. Some evidence for the moderating effects of hormones on the level of aggression expressed by Type As was observed. No direct relationship between Type A and aggression was found.  相似文献   
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This study analysed the way 20 managers in the information technology industry in Australia viewed their lives, and identified two dimensions of central importance cutting across the work, family and leisure spheres encompassed by them. One dimension was positively loaded towards activities which were challenging, creative and under the individual's control. These activities were enjoyable, and included examples such as consulting with clients, creating new business, and communicating and dealing with others, whether at work or at home. The opposite pole of this dimension involved activities such as completing paperwork, general administration, doing the shopping, and disciplining the children. Such activities were seen as necessary, routine or stressful, and were generally disliked. The other dimension dealt with activities which, at one pole, were emotionally involving or involved moral standards, and included examples such as attending meetings, doing things as a family, and settling disputes, either at work or at home. At the other pole were activities which were usually done alone and involved no sense of social or moral obligation. Leisure activities typically fell into this category. The results indicated that these managers generally pursued a lifestyle which was seen to be non-stressful, and one valued for the challenge, enjoyment, freedom of choice and personal control which it offered.  相似文献   
48.
Victims' perceptions of social support: what is helpful from whom?   总被引:5,自引:0,他引:5  
Although research has demonstrated that social interactions influence psychological well-being, little is known about what specific actions victims of stressful life events experience as helpful or unhelpful. Wortman and Dunkel-Schetter (1979) previously suggested that victims frequently experience rejection, withdrawal, and communication problems with those close to them. To address these issues, 55 cancer patients were interviewed concerning the specific actions they found to be helpful or unhelpful from several potential support providers: spouse, other family members, friends, acquaintances, others with cancer, physicians, and nurses. The data indicated that the Wortman and Dunkel-Schetter victimization model applied better to interactions with friends and acquaintances than to interactions with close family members. In addition, support was found to be partially dependent on the source: Particular actions were perceived to be helpful from some but not other network members. Implications for theory and research on social support are discussed.  相似文献   
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The concurrent validity of the motor domain from the Vineland Adaptive Behavior Scales was estimated using scores from the Peabody Developmental Motor Scales as criteria. A moderately high correlation between the measures was obtained. Implications, particularly for preschool children, were discussed.  相似文献   
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Many “higher” animals are commonly assumed to distinguish between individual humans. This belief is based largely on anecdotal reports; in reality, there is little empirical evidence to support human recognition in nonhuman species. We report that laboratory rats consistently chose a familiar human over an unfamiliar human following fourteen and five 10-min exposures and even following a single 10-min exposure. Furthermore, this preference was retained in the absence of additional contact for at least 5 months. These results confirm that laboratory rats can tell individual humans apart, a prerequisite for associating them with hedonic events. Such human-based conditioning, described by Pavlov and by Gantt, Newton, Royer, and Stephens (1966), may have important implications for animal research in a variety of settings.  相似文献   
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