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81.
Approximately 15% of all papers appearing inPsychometrika during the period 1960–1984 have been statistical or data analytic in nature. While these papers cover a very wide range of issues and are technically quite similar to those appearing in other major statistical journals, collectively they possess features which make them identifiablyPsychometrika.  相似文献   
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A variety of studies withhabitual users of nicotine, caffeine, cocaine, and amphetamines have shown that administration of these stimulants has the paradoxical effect of lowering arousal states. Research on transmarginal inhibition shows that when subjects are presented with a succession of stimuli monotonically increasing in intensity, GSR and related arousal responses increase first and then begin to decline beyond a certain point of stimulus intensity. That is, following repeated exposure to intense stimuli, continued more intense stimulation has the effect of lowering arousal. Since stimulants subjectively heighten stimulus intensity, the transmarginal inhibition data provide a basis for explaining opposing effects of stimulants on arousal, depending on dose and frequency of use. It was hypothesized that when dose levels are low and usage is infrequent, arousal increases with stimulant intake. In contrast, when dose levels are high and frequent, arousal shows decrements with new intakes of stimulant. A new questionnaire measure of characteristic arousal was developed and correlated with subjects' reports of habitual levels of stimulant and sedative intake. Weekly total stimulant use correlated significantly and negatively with characteristic arousal level, providing support for the hypothesis. This lowered arousal of frequent stimulant users was not a confound of, or due to, concomitant frequent sedative use, since total stimulant and sedative use levels were uncorrelated.The author would like to thank Janice Schafrik for running the subjects in this study.  相似文献   
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The experiments examined the contributions of forebrain noradrenaline and environmental enrichment to recovery of place navigation ability in rats after hemidecortication in infancy or adulthood. Noradrenaline depletion did not affect recovery from neonatal hemidecortication, although the early hemidecortications did allow sparing of function relative to adult operates. Noradrenaline depletion also failed to attenuate the positive effects of enriched housing on otherwise normal rats. Noradrenaline depletion did retard recovery of adult hemidecorticate rats housed in standard laboratory cages, but it did not retard recovery of adult hemidecorticate rats housed in enriched environments. The results suggest that noradrenaline is importantly involved in enhancing recovery from brain damage when other sources of compensation (e.g., neonatal injury, enriched environment) are absent.  相似文献   
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Attitudes toward posthumous organ donation and commitment to donate   总被引:4,自引:0,他引:4  
The medical need for human organs suitable for use as transplants far exceed the supply, and is growing. More favorable attitudes about organ donation would increase people's willingness to sign posthumous donation pledges. But effective educational programs require information about the public's present views. Verbal attitude scales were constructed and administered to 110 adults, resulting in reliable measurement of two independent dimensions, prodonation and antidonation (r = .003). Cluster analysis of the instrument revealed that the positive dimension involves belief in the humanitarian benefits of organ donation and feelings of pride experienced by the donor. The negative dimension reflects fears of body mutilation and of receiving inadequate medical treatment when one's life is at risk. Pro and anti scores in combination predicted willingness to sign a donor card. A 2 X 2 analysis of variance (High-Low Positive X High-Low Negative) revealed significant main effects for both positive and negative attitude. Also, a significant interaction effect was obtained. Those subjects who had both strong positive attitudes and weak negative attitudes were especially willing to sign donor cards. Suggestions for designing educational campaigns to promote organ donation are offered.  相似文献   
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This study tested the applicability of a cognitive-motivational model of health behavior to children's food choices. A sample of 107 elementary schoolchildren provided ratings of 15 foods in terms of possible choice criteria (e.g., how tasty or healthful specific foods were) and social or environmental influences (e.g., whether foods were eaten by friends or were easy to get). Several measures of food consumption were taken, and cognitive-developmental level was assessed. Within-person correlations were calculated between food choices and each choice criterion and social/environmental factor. These "correlational indices" of influences on food choice subsequently were used to identify five distinct subgroups in the sample. Children at the operational level of cognitive development tended to be in one of three groups characterized by health orientation in food choice, taste orientation, or multiple-motive orientation. Dietary quality was poorest in the taste-oriented group. Children at the preoperational level tended to have one of two undifferentiated patterns of values across the correlational indices. Results provide evidence of: the viability of cognitive-motivational models to explain children's food choices, the promise of within-person research methodology, and the potential for enhanced health behavior-change programs by use of population segmentation and tailored interventions.  相似文献   
88.
Psychopathology and symptom patterns were studied in 60 former prisoners-of-war (POWs) by administering standardized tests including the Minnesota Multiphasic Personality Inventory (MMPI), an adjustment problem checklist, and a structured clinical interview. Most POWs showed marked psychological impairment, but modal profile analysis identified two prototypic MMPI patterns, which differed in pervasiveness and type of psychopathology. Profile subtypes were defined by unique clusters of clinical symptoms and differed in confinement stress severity. The typology of symptoms argues against a homogeneous conceptualization of stress-induced disorders and suggests the need for definition of the severity and subtype of stress phenomena and individual difference factors in responding to trauma.  相似文献   
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This study examined the implications for social comparison theory of the proposition that women have lower self-confidence than men when there is a socially defined standard of performance. To this end, it was hypothesized that women would judge themselves to be similar to a lower ranked person, whereas men would judge themselves to be similar to a higher ranked person. Furthermore, it was hypothesized that women would choose to see a score lower than their own, whereas men would choose to see a score higher than their own. The results on the measure of similarity indicated that men did judge themselves to be similar to a higher ranked person, whereas women showed no consistent preferences in their judgments of similarity. The results on the choice of a comparison other were not as clear-cut.  相似文献   
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For the last century, moral philosophy has stressed theory for the analysis of moral argument and concepts. In the last decade, interest in the ethical issues of health care has stimulated attention to cases and particular instances. This has revealed the gap between ethical theory and practice. This article reviews the history and method of casuistry which for many centuries provided an approach to practical ethics. Its strengths and weaknesses are noted and its potential for contemporary use explored.  相似文献   
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