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31.
Three experiments tested the efficacy of the phonetic mnemonic system under varying conditions of application. The first study attempted unsuccessfully to replicate and extend the work of Morris and Greer (1984), who had shown training in the phonetic mnemonic method to facilitate memorization of a serial list of two-digit numbers. In the present study, subjects trained in the phonetic mnemonic method failed to learn lists of two-, four-, and six-digit numbers better than control subjects. The second experiment partially replicated the first, the differences being that training in the phonetic mnemonic method was strengthened, and time allotted for number recall was extended. Under these circumstances the phonetic mnemonic group recalled the two-, four-, and six-digit numbers significantly better than the control groups, a finding conforming with Morris and Greer's (1984) results. The third experiment partially replicated the second, everything being the same except that, in this case, subjects constructed their own key words representing each number, instead of these words being supplied by the experimenter. Under these conditions, subjects trained in the phonetic mnemonic method recalled significantly fewer numbers than control subjects.  相似文献   
32.
This paper is a general survey of ethical issues related to the artificial heart. It begins by looking at the history of funding of the artificial heart program through the National Institute of Health in 1965. Attention is paid to the problem of the lack of planning related to social, ethical, economic, and legal implications. The paper then deals with three areas of ethical concerns. They are those issues relating to the experimental versus therapeutic benefits, the cost, and public involvement with a private interest.  相似文献   
33.
Paul Yu  Gary Fuller 《Synthese》1986,66(3):453-476
This essay is intended to be a systematic exposition and critique of Daniel Dennett's general views. It is divided into three main sections. In section 1 we raise the question of the nature of a plausible scientific psychology, and suggest that the question of whether folk psychology will serve as an adequate scientific psychology is of special relevance in a discussion of Dennett. We then characterize folk psychology briefly. We suggest that Dennett's views have undergone at least one major change, and proceed to discuss both his earlier and his later views.In section 2 we suggest that Dennett is correctly perceived as an instrumentalist in his earlier works. We think that Dennett later abandons this position because of general worries about instrumentalism and, more importantly, because Dennett became convinced that an instrumentalist conception of folk psychology will not enable us to vindicate the notions of personhood, moral agency, and responsibility. This left Dennett with a dilemma. On the one hand, he does not think that beliefs, etc., will turn out to be genuine scientific posits. On the other hand, he thinks that moral agency would be impossible if we could not treat beliefs, etc. as causally efficacious in some suitable sense.In section 3 we discuss Dennett's resolution of this dilemma. The key to his current view, we suggest, is the illata-abstracta distinction. Dennett holds that both illata and abstracta are real and have causal powers, even though only illata are genuine scientific posits. He suggests that beliefs etc. are abstracta, and are the subject matter of what he calls intentional system theory. The subject matter of another theory, what Dennett calls subpersonal cognitive psychology, are illata, which are subpersonal intentional states. The important point is that this distinction lets Dennett have it both ways: (i) Since beliefs are mere abstracta, we need not commit ourselves to the thesis that beliefs will turn out to be posits of an adequate scientific psychology. (ii) Since beliefs have causal power, we are assured of moral and rational agency. We shall argue that Dennett's current view is untenable. If we are right in our arguments, then Dennett's program to produce a scientifically plausible psychology, one that will turn out to vindicate folk psychology (in some suitable sense), is a failure. It fails in the following important ways: (i) What Dennett sketches — intentional system theory cum subpersonal cognitive psychology — is not a plausible scientific psychology. (ii) As a consequence, Dennett also fails to provide a satisfactory foundation for moral and rational agency.  相似文献   
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Gary N. Powell 《Sex roles》1986,14(1-2):9-19
Individuals' own definitions of sexual harassment ultimately influence the success of their companies in responding to the Equal Employment Opportunity Commission's (EEOC) guidelines against sexual harassment. Previous research has consistently shown that women see more sexual harassment than do men. However, sex differences in definitions of sexual harassment could be explained by sex role identity. Results from a study of undergraduate business students and MBA students holding full-time jobs instead reaffirmed the existence of a sex effect and revealed the presence of a Sex X Masculinity interaction effect. Subjects' femininity had a minor effect on their definitions of sexual harassment.A previous version of this article was presented at the Academy of Management Meeting, Dallas, August, 1983. Appreciation is extended to Lisa A. Film for her assistance with data analysis.  相似文献   
36.
The brightness of brief displays whose durations do not exceed a critical period of integration is known to covary with stimulus duration (Bloch’s law). There are cases in which the interdependence of duration and brightness introduces an unwanted confounding that must be avoided. Three methods for equating the brightness of brief stimuli displayed under computer control are described and evaluated, and an example of the outcome obtained with the most efficient procedure is reported.  相似文献   
37.
Pregnant primiparous rats were subjected to four days of light restraint stress on postconception days 7 through 10, inclusive, coincident with the development of the fetal gastrointestinal system. Twenty male and twenty female offspring from prenatally stressed and nonstressed rats were then subjected to two hours of supine cold-restraint as adults. Eighty percent of nonprenatally stressed offspring developed gastric lesions, while 47.5% of offspring of prenatally stressed mothers displayed lesions. A significant sex-stress interaction was detected, indicating that male offspring from prenatally stressed mothers display less severe gastric lesions in response to restraint stress as adults than do male offspring from nonprenatally stressed mothers. Female offspring from both prenatal stress conditions showed similar levels of stress-induced lesions.  相似文献   
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39.
Three experiments are described which elaborate some of the conditions under which rats will contact and manipulate a periodically presented retractable lever. Experiment 1 demonstrated that (i) initial manipulative oral and manual contact with the lever was facilitated if the rat had previous experience of food delivery in the experimental chamber; (ii) persistence in contacting the lever on successive presentations was a function of whether food continued to be presented in the experimental environment; and (iii) food satiation significantly reduced the tendency of the rat to contact the lever even though an expectancy of food had previously been established under conditions of food deprivation. Experiment 2 suggested that the tendency to approach and contact the lever was in part a function of the local moment-to-moment conditional probability of food delivery. Experiment 3 found that the probability of contacting the lever was higher during presentation of an auditory CS signaling a high rate of food delivery than during stimuli signaling no food at all. These results are interpreted as suggesting that the food-signaling aspects of an appetitive CS and that CS's ability to generate signal-directed behaviors are experimentall separable properties.  相似文献   
40.
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