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991.
The goals and ends of contemporary medicine are often unclear. An explicit inquiry into the religious dimensions of healing offers an important perspective from which to evaluate the potential capabilities of the medical profession. This paper describes a course in which medical students joined divinity students to explore areas of mutual intellectual, professional, and personal interest. Students and faculty examined in depth three broad areas in which medicine and religion share common ground: concepts of health and illness from the religious perspective, approaches to the understanding of suffering and meaning, and the shared professional stresses of physician and clergy.This paper comes from the Department of Medicine, Beth Israel Hospital, and the Division on Aging and the Program for the Analysis of Clinical Strategies, Harvard Medical School, and the West Roxbury-Brockton Veterans Administration Geriatric Research, Education and Clinical Center, Boston.  相似文献   
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Variable-interval schedules of timeout from avoidance   总被引:2,自引:2,他引:0       下载免费PDF全文
Rats were trained on concurrent schedules in which pressing one lever postponed shock and pressing the other occasionally produced a 2-min timeout during which the shock-postponement schedule was suspended and its correlated stimuli were removed. Throughout, the shock-postponement schedule maintained proficient levels of avoidance. Nevertheless, in Experiment 1 responding on the timeout lever was established rapidly, was maintained at stable levels on variable-interval schedules, was extinguished by withholding timeout, was reestablished when timeout was reintroduced, and was brought under discriminative control with a multiple variable-interval extinction schedule of timeout. These results are in contrast with Verhave's (1962) conclusion that timeout is an ineffective reinforcer when presented to rats on intermittent schedules. In Experiment 2 the consequence of responding on the timeout lever was altered so that the shock-postponement schedule remained in effect even though the stimulus conditions associated with timeout were produced for 2 min. Responding extinguished, indicating that suspension of the shock-postponement schedule, not stimulus change, was the source of reinforcement. By establishing the reinforcing efficacy of timeout with standard variable-interval schedules, these experiments illustrate a procedure for studying negative reinforcement in the same way as positive reinforcement.  相似文献   
994.
We develop a simple model of switching between the initial links of a concurrent-chain procedure. Behavior is determined by four parameters μ1, μ2, q1, and q2. The first two are the basic rates of switching from Schedule 1 and Schedule 2, respectively. The second two are the probabilities of leaving Schedule 1 and Schedule 2 after the corresponding terminal link has been completed. We show that for fixed values of these four parameters, the relative allocation on the initial links may change as a result of changes in initial-link schedules. The effect can be quite large if the switching rates are low. An implication is that relative allocation is not necessarily a good measure of behavior.  相似文献   
995.
The psychology of self-esteem bypasses consequential issues of everyday behavior and moral responsibility in favor of pursuing a global goal of enhanced self-esteem on the assumption that happiness, success, and responsible behavior will automatically follow. The goal is vague and ways of achieving it are confused and conflicting. Greater attention to concrete tasks and challenges and sensitivity to moral issues could help make therapy more clear, effective, and socially useful.  相似文献   
996.
Pigeons' responses were reinforced on a variant of a mixed variable-interval extinction schedule of reinforcement in which the transition to the higher reinforcement rate was signaled by a trace stimulus projected on the response key prior to the onset of the component correlated with food delivery. In the first of two experiments, the duration of the trace stimulus preceding the component correlated with food delivery was varied from 1.5 to 50.0 s and in the second experiment, the reinforcement frequency in the same component was varied from 10 to 60 reinforcers per hour. Pigeons pecked at the trace stimulus preceding the onset of the component correlated with food delivery even though responding was not reinforced in its presence and only one of the changes in reinforcement rate (i.e., from extinction to reinforcement) was signaled. The rate of pecking during the trace stimulus was a function of its duration but not of the reinforcement frequency in the following component. Higher rates generally occurred at the shorter trace-stimulus durations. Component responding following the offset of the trace stimulus was under discriminative control of the trace stimulus whether or not responding occurred in the presence of the trace stimulus.  相似文献   
997.
Little is known about the personal life of John B. Watson, and this interview aims at capturing the personality of the founder of American behaviorism through the eyes of his son, James B. Watson. Today, psychologists and other social scientists increasingly realize that there is an intimate link between the biography of a psychologist and the kind of psychology he or she founds. Thus biographical information about a founding psychologist can help researchers make explicit this essential link.  相似文献   
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