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861.
Behavioral economics of concurrent ethanol-sucrose and sucrose reinforcement in the rat: effects of altering variable-ratio requirements. 总被引:2,自引:2,他引:0 下载免费PDF全文
These experiments examined the own-price and cross-price elasticities of a drug (ethanol mixed with 10% sucrose) and a nondrug (10% sucrose) reinforcer. Rats were presented with ethanol-sucrose and sucrose, both available on concurrent independent variable-ratio (VR) 8 schedules of reinforcement. In Experiment 1, the variable ratio for the ethanol mix was systematically raised to 10, 12, 14, 16, 20, and 30, while the variable ratio for sucrose remained at 8. Five of the 6 rats increased ethanol-reinforced responding at some of the increments and defended baseline levels of ethanol intake. However, the rats eventually ceased ethanol-reinforced responding at the highest variable ratios. Sucrose-reinforced responding was not systematically affected by the changes in variable ratio for ethanol mix. In Experiment 2, the variable ratio for sucrose was systematically increased while the ethanol-sucrose response requirement remained constant. The rats decreased sucrose-reinforced responding and increased ethanol-sucrose-reinforced responding, resulting in a two- to 10-fold increase in ethanol intake. Experiment 3 examined the substitutability of qualitatively identical reinforcers: 10% sucrose versus 10% sucrose. Increases in variable-ratio requirements at the preferred lever resulted in a switch in lever preference. Experiment 4 examined whether 10% ethanol mix substituted for 5% ethanol mix, with increasing variable-ratio requirements of the 5% ethanol. All rats eventually responded predominantly for the 10% ethanol mix, but total amount of ethanol consumed per session did not systematically change. In Experiment 5, the variable-ratio requirements for both ethanol and sucrose were simultaneously raised to VR 120; 7 of 8 rats increased ethanol-reinforced responding while decreasing sucrose-reinforced responding. These data suggest that, within this ethanol-induction procedure and within certain parameters, demand for ethanol-sucrose was relatively inelastic, and sucrose consumption was independent of ethanol-sucrose consumption. Demand for sucrose, on the other hand, was relatively elastic, and ethanol-sucrose readily substituted for it. The results are discussed in terms of applying a behavioral economic approach to relationships between drug and nondrug reinforcers. 相似文献
862.
Daniel Alroy 《Synthese》1995,104(1):147-160
Neural impulses from the senses to the brain convey information, not sensation. The direct electrical stimulation of the cortex produces sensations. Hence, such sensations are evoked in the brain, and not received from the senses, nor from the outside world through the senses. More specifically, the experience of light is evoked in the brain and not received from the eyes. Consequently, the born blind, too, would experience light in response to electrical brain stimulation. The luminosity of light is not a property of electromagnetic radiation. If the experience of light is private, then so are the visual observations it makes possible. 相似文献
863.
Bruce G. Link Sharon Schwartz Robert Moore Jo Phelan Elmer Struening Ann Stueve Mary Ellen Colten 《American journal of community psychology》1995,23(4):533-555
Media reports suggest that the public is becoming impatient with the homeless—that so-called “compassion fatigue” has gripped the nation. This characterization of public sentiment could have important policy consequences—restrictive measures can be justified by growing public impatience, and progressive housing policies seem infeasible within a hostile climate of opinion. But evidence to support the compassion fatigue notion is anecdotal. We examine the issue by tracking the results of public opinion polls and by reporting detailed evidence from a nationwide random-digit dial telephone survey (N=1,507) concerning knowledge attitudes and beliefs about homeless people. To be sure, the public sees homelessness as an undesirable social problem and wants something done about it. However, although the homeless are clearly stigmatized, there is little evidence to suggest that the public has lost compassion and is unwilling to support policies to help homeless people. 相似文献
864.
Applying market principles to the delivery of careers guidance services: A critical review 总被引:1,自引:0,他引:1
A. G. Watts 《British Journal of Guidance & Counselling》1995,23(1):69-81
Market principles can be applied to careers guidance services through the concept of guidance as market-maker or through the concept of a market in guidance. The notion of a market in guidance can take the form of a real market or of a quasi-market. A quasi-market can take the form of contracts or of vouchers. These three sets of options are explored in relation to current policy developments in the careers guidance field. 相似文献
865.
This study compares and contrasts the use of gender-related concepts in other-and self-perception. The schematic use and stereotypic and affective meanings of feminine and masculine were derived from hierarchical classes analysis (HICLAS) of participants' (N = 72; 50 females, 22 males, 54% white) ratings of self and significant others. The study reveals that people use these concepts differently in their perception of others than in their perception of self. In addition, the meaning of masculine and feminine constructed by these participants differs significantly from their traditional definitions. Finally, being feminine is evaluated more positively than being masculine in the perception of others, while the ego protective function of gender leads participants to evaluate their own gender's features most positively in self-perception.This article was presented at the 1993 Eastern Psychological Association, Washington, DC, April 1993. The collection of the data reported in this paper was supported by National Institute of Mental Health Grant MH40871-03/04. We thank the Institute for its support. We also thank the participants in this study for sharing their lives with us. Finally we would like to thank Richard Ashmore, Rae Carlson, and Basil Englis for comments on earlier drafts of this paper. 相似文献
866.
Stephen G. Weinrach 《Journal of counseling and development : JCD》1995,73(3):296-300
Objections to Rational-Emotive Behavior Therapy (REBT) seem to exceed the mere rational preference for one approach over another. Ziegler suggested that James's dichotomy between Tough- and Tender-Mindedness might explain REBT's appeal to some and its failure to attract others. REBT is a predominantly Tough-Minded therapy, but the counseling profession is largely Tender Minded. In this article, the author examines why Tender-Minded counselors may not accept REBT, what common misperceptions of REBT may contribute to this rejection, and how the two might be reconciled. Intervention strategies for Tender-Minded counselors are suggested. 相似文献
867.
Gary G. Gintner 《Journal of counseling and development : JCD》1995,73(3):346-351
Research shows that misdiagnosis can have particularly damaging consequences in older adults. It is frequently difficult, however, to determine whether observed symptoms are due to aging or to a medical condition. The author examines three common disorders that can be particularly challenging to diagnose in older adults: dementia, depression, and delirium. Three general questions are discussed for each: What are the age-related differences in the disorder's presentation? What medical issues need to be ruled out? What assessment methods are particularly useful in the diagnostic process? 相似文献
868.
Janine S. Shelby Michael G. Tredinnick 《Journal of counseling and development : JCD》1995,73(5):491-497
Crisis intervention has typically been conceptualized as seeking a return of clients to a state of equilibrium. Our work with Hurricane Andrew survivors in south Florida, as part of the Disaster Mental Health Services team of the American Red Cross, has led us to appreciate the importance of several further considerations. In our work, we developed a proactive approach, attempting to recognize and extend clients' preexisting strengths. We offer a number of pragmatic interventions, focusing particularly on children's issues and we draw attention to sensitive multicultural issues. 相似文献
869.
Weiss G 《希帕蒂亚:女权主义哲学杂志》1995,10(1):202-217
A critical application of Ruddick's model of maternal thinking is the best way to grapple with the ethical dilemmas posed by sex-selective abortion which I view as a "moral mistake." Chief among these is the need to be sensitive to local cultural practices in countries where sex-selective abortion is prevalent, while simultaneously developing consistent international standards to deal with the dangers posed by the use of sex-selective abortion to eliminate female fetuses. 相似文献
870.