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Estimates of the probability of various outcomes associated with treatment for kidney failure were made by chronic dialysis patients, dialysis patients awaiting transplant, successful transplant patients, and unsuccessful transplant patients back on dialysis. The latter two groups can be considered a natural experiment testing the impact of personal experience on population predictions. Consistent with the law of small numbers and the availability heuristic, successful transplant patients gave higher estimates of the population success rate for transplantation than unsuccessful transplant patients gave.  相似文献   
104.
Relative outcomes in social commerce with peers are potent determinants of cognitions and behavior in young children. Although there has been considerable attention given to the behavioral consequences of social comparisons following the receipt of rewards, there has been less concern with cognitive or affective consequences. Additionally, little is known about the accrued effects of multiple social comparison experiences that may be consistent or inconsistent with one another. In the present study, young children received a constant level of reward but the amount they saw a peer receive was varied. There were two sequences of reward distribution, and in a given sequence children received either the same number of rewards as the peer (=), more (+), or fewer (?). In a 3 × 3 factorial design all possible combinations occurred. A negative inequality in reward distribution, no matter where it fell in a sequence, made children sad and inclined children to distribute fewer rewards to peers. When a sequence contained an initial experience of positive inequality, children decreased subsequent levels of self-reward. Experiencing a comparison that revealed a negative inequality in reward distribution also disrupted children's accuracy in appraising the overall distribution of rewards: even when an initial negative inequality was completely offset by an equivalent experience of positive inequality, children inaccurately concluded that they had received fewer rewards than their peers.  相似文献   
105.
The influence of perceived somatotype on stereotypes of behavior associated with body build was investigated among 160 male and 140 female Nigerian children in secondary school. In both groups, the perception of subjects' own physiques and discrepancy between their perceived and preferred physiques significantly explained the variance in the character trait scores attributed to body types. In general, the subjects attributed positive character traits to their perceived somatotypes and undesirable traits to the physiques with which they were dissatisfied. Thus, the perception of somatotype and discrepancy between perceived and preferred physique could significantly differentiate the character traits attributed to body build among male and female children.  相似文献   
106.
The effects on aggressive behavior, open-field activity, and pain threshold of bilateral microinjections of serotonin (20 micrograms) and quipazine (20 micrograms), the direct serotonergic receptor agonist, into the cortico-medial amygdala were investigated in Wistar rats. Both drugs significantly prolonged the attack latency in isolated killer rats (predatory aggression model), and suppressed the incidence of aggressive postures/attacks in shock-induced fighting test (affective aggression). The only difference in the open-field behavior was the lower number of central square entries in drug-treated compared to saline-injected rats. None of the substances produced any significant change in jump threshold. It is concluded that stimulation of serotonin receptors within the amygdala produces inhibition of affective and muricidal behavior in isolated rats. The effect does not seem to be dependent on changes in general activity and pain sensitivity.  相似文献   
107.
Seventy-five medium-light smokers rated their performance for smoking in 25 situations covering a range of high- and low-stress situations. Information on personality, age, sex, length of habit, number of cigarettes smoked, amount inhaled and amount of cigarettes smoked was also obtained. Six main factors were extracted by principal-factor analysis which were related respectively to situations involving preparatory activity, attentional stress, neutral relaxation conditions, unpleasant (anxiety) and pleasant (excited) emotional stress and social vs isolated activity. Smokers who scored high on Neuroticism tended to smoke more when experiencing unpleasant emotions; older smokers smoked predominantly in pleasant relaxing conditions; extraverts and low-activity situational smokers, reported inhaling more. A model of smoker motivation is developed which suggests that both pharmacological and psychological factors contribute to habit maintenance. Three basic motivational types of smokers are identified: high-stress smokers for whom smoking is a secondary activity, and who rely on smoking to form a minor distraction for their current task. Low-activity smokers who wish to act, or change their current affective state in some way and who rely on pharmacological factors. Neutral relaxation smokers for whom smoking is a pleasurable activity in its own right.  相似文献   
108.
Previous studies have examined intra-individual aggregation in the use of cigarettes, alcohol, and coffee by examining the co-occurrent use of any pair of these three substances. A recent literature review failed to find a single investigation that studied use of all three in the same sample. In the present study, co-occurrent use of all three of these substances was examined in crossvalidated subsamples of 226 male and 245 female healthy, community-living, middle-class Americans. A log-linear analysis was used to compare the proportion of smokers, ex-smokers, and nonsmokers categorized as users of more or less amounts of coffee and alcohol. Although most of the intercorrelations were not strong, the results indicate that for both sexes, smokers and ex-smokers were more likely than nonsmokers to drink greater amounts of alcohol and coffee. Furthermore, for smokers, ex-smokers, and nonsmokers, a majority of individuals who reported drinking more alcohol also reported drinking more coffee. Interestingly, the coffee and alcohol consumption levels of ex-smokers resembled those of smokers more than those of nonsmokers. Also, ex-smokers reported drinking more wine and decaffeinated coffee than either smokers or nonsmokers. Finally, the number of cigarettes smoked per day (daily quantity) was positively related to total alcohol and coffee consumption in men, but not in women. Further studies are recommended to examine the role of individual differences in the development, maintenance, and modification of these three appetitive habits and their co-occurrence.  相似文献   
109.
Immediately after their first use of the dissecting room, 45 preclinical medical students rated their enthusiasm and reluctance at seven points along a time sequence encompassing their experience from the night before to the completion of their first dissection. A second group of 42 preclinical medical students carried out the same ratings in real time. A naive group of 24 psychology students were asked to imagine a first visit to the dissecting room and rate their imagined feelings in the same way. Gradients for reluctance for the two experimental groups rose to maxima at the point of entering the dissecting room. The reluctance gradient for the naive group and the enthusiasm gradients for all three groups, prior to this point, were zero. These are discussed as negative and positive motivational gradients that meet the predictions of approach/avoidance theory (Miller, 1959).  相似文献   
110.
A modification in scoring the ABC Scale   总被引:1,自引:0,他引:1  
The scoring procedures for the Articulation of the Body-Concept (ABC) Scale to use with three-, four- and five-year-old children were modified to determine their degree of field-dependence-independence. A total of 300 children, who obtained a score of one or better on the ABC Scale, were administered the Preschool Embedded Figures Test (PEFT) and the ABC Scale. The ABC Scale was scored using its scoring procedures and the scoring procedures for the Goodenough-Harris Drawing Test (GHDT). Scores on the PEFT, ABC Scale and GHDT were correlated with each other. Correlations among all cognitive measures ranged from .88 to .99, which were high and statistically significant (p < .0001). Therefore, the scoring procedures for the GHDT can be substituted in scoring the ABC Scale in assessing young children's field-dependence-independence.  相似文献   
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