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51.
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   
52.
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   
53.
The present study examined some previously reported relationships between drug use by adolescents and perceived attitudes and behaviors of their parents. An anonymous questionnaire was administered to the student body of an inner-city secondary school for difficult students. Relationships between parental use of drugs and adolescent use of the same drugs were moderate and roughly equivalent across drugs. However, parental use of marijuana was strongly related to the adolescent's use of other, harder drugs such as opiates, cocaine, amphetamines, and barbiturates. This finding is explained within the framework of Kandel's postulated stages of drug initiation. It points to a need for further study of parental influences, which may be increasingly problematic as more individuals who have grown up in our marijuana-accepting society become parents of adolescents.  相似文献   
54.
The Family Adaptability and Cohesion Evaluation Scales (FACES), a measure of family functioning, contains three scales: cohesion, adaptability, and social desirability. These were slightly modified (FACES- R) on the basis of pilot data and were administered to 42 clinic families (families seeking or receiving psychological services) and 206 nonclinic families. Support for the scales was found in high coefficient alpha reliabilities and similarity of the sample means and standard deviations to those of the standardization sample. However, there was little agreement among family members' scale scores. Therapists' ratings of cohesion and adaptability did not correlate with scale scores among clinic families. There was no difference between clinic and nonclinic samples on the cohesion or adaptability scales, although the social desirability scale did discriminate between groups. Factor analysis suggested that cohesion, adaptability, and social desirability cannot be clearly differentiated using this measure.This work was supported by the American Association of University Women and by Grant R01HD13820 from the National Institute of Child Health and Human Development.  相似文献   
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Two experiments examined whether individuals who ascribe the disparity in the performances of two actors to situational constraints adequately adjust their dispositional inferences to reflect their own perceptions of causality. Using the quiz-game format of L. D. Ross, T. M. Amabile, and J. L. Steinmetz (1977, Journal of Personality and Social Psychology, 35, 485–494), the effects of the subjects' awareness of the role-determined, self-presentation advantage of the questioner on their dispositional inferences concerning the quiz-game participants are noted. It is hypothesized that subjects who indicated full awareness of the determining force of the situation would nevertheless draw more favorable dispositional inferences about the questioner than about the contestant. The prediction is confirmed. Although the situationally aware subjects rate the questioner and contestant more similarly than do the other subjects, they still rate the questioner higher in knowledge, memory, and education. The results of Experiment 2 indicate that increasing the salience of the subjects' assessment of the situational advantage of the questioner does not eliminate the disparity. It is proposed that the fudamental attribution error represents more a failure to adjust trait inferences for causal attributions than a misperception of causality. Implications concerning the relationship between knowledge of causality and social judgment and the utility of the distinction between “perceived causality” and “higher order causal inferences” are discussed.  相似文献   
57.
The relative effectiveness of incentive and minimal justification techniques in promoting electrical energy conservation among 90 homeowners was investigated. Subjects in the Questionnaire condition were asked to complete a short energy conservation survey. Those in the Commitment condition were asked to curtail their consumption of electricity by 15%. In the Questionnaire + Commitment condition, subjects received both requests. These three groups were compared to an Incentive condition, where individuals were offered a highly attractive monetary incentive for conserving electricity, a Questionnaire + Commitment + Incentive condition, and a Control condition. The groups did not differ in electricity consumption during baseline, initial request, or follow-up periods. However, during the conservation period, homeowners in the Commitment and the combined treatment groups conserved more electricity and contained more conservers than either of the remaining groups. These outcomes were discussed in terms of the comparative effectiveness of minimal justification and incentive strategies for inducing behavioral change.  相似文献   
58.
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   
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60.
Civic actions are behaviours intended to improve conditions for others or help shape a community's future. Such actions vary widely from voting to voluntary helping, from canvassing to community organizing, and attempts have been made to categorize the array of civic actions. However, the question of why young adults engage in some types of civic actions versus others is not well understood. Using data from 598 White, cisgender, heterosexual young adults in the United States, we examined the relations between individual civic efficacy, collective civic efficacy, and seven actions: writing social media posts, voting, buycotting, volunteering, participating in an organization, supporting political candidates, and protesting. We hypothesized that individual efficacy would be positively related to all seven actions, but collective efficacy would be more strongly related to collective or political actions, compared to the individual or civil ones. Logistic regression analyses showed that individual efficacy positively predicted engagement in all seven civic actions. Individual and collective efficacy had a complex curvilinear relation with buycotting and supporting political candidates. Implications for future research and applications aimed at promoting civic engagement amongst young adults are discussed. Please refer to the Supplementary Material section to find this article's Community and Social Impact Statement .  相似文献   
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