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351.
Sharon Sterling Emory L. Cowen Roger P. Weissberg Bohdan S. Lotyczewski Mary Boike 《American journal of community psychology》1985,13(1):87-98
A group of 211 first-to fourth-grade children who had experienced one or more recent stressful life events were compared to a demographically matched sample of 211 children who had not experienced such events on measures of school adjustment problems and competencies. Stressful life events were found to be associated with the presence of more serious school adjustment problems and fewer competencies. Those associations were strongest for children who had experienced multiple recent stressful events. The importance of preventive interventions for this at-risk group was emphasized and future research steps in the area were considered. 相似文献
352.
Preweanling (21 days old) and adult (60-80 days old) rats were exposed to ethanol odor either paired with the early stages of apomorphine-induced toxicosis, paired with the recovery from toxicosis, or unpaired with the induction of distress. Twenty four hours later, ethanol preferences were measured in a spatial olfactory test (ethanol vs lemon odor) or a drinking test (5.6% v/v ethanol vs 0.25% w/v citric acid solutions). During the olfactory test both young and adult rats expressed substantial ethanol odor aversions when previously exposed to this odor paired with toxicosis. However, changes in ethanol intake became apparent only in preweanling subjects. Preweanlings which received the ethanol odor paired with illness drank significantly less of the ethanol solution relative to controls, while subjects experiencing the odor paired with recovery from distress significantly increased their consumption of the ethanol solution. These prior aversive and appetitive olfactory experiences had no effect upon ethanol intake in adult rats. These results implicate both an ontogenetic and a sensorial factor in the regulation of ethanol intake. 相似文献
353.
The suppression of corticosterone synthesis with metyrapone (25 mg/kg) reduced the hyperactivity and altered the exploratory activity of hippocampally lesioned animals (HPC) in the open field to the level of cortical and sham controls (Experiment 1). In a second experiment, corticosterone (600 micrograms/kg) pretreatment 2 h, but not 1 h, before metyrapone partially restored the hyperactivity of HPC animals that had been decreased by the corticosteroid-suppressant drug. Alterations in exploratory behavior induced by metyrapone were also prevented by corticosterone pretreatment. The results suggest that the suppression of corticosterone in hippocampally lesioned animals produces a normalization of behavior that can be prevented by pretreatment with corticosterone. 相似文献
354.
Joy Patricia Burke Jeanne P. Hunt Robert L. Bickford 《Journal of research in personality》1985,19(3):321-329
In the present investigation, we integrated self-theories (specifically, theories of cognitive consistency and self-esteem) with attribution theory. Our intent was to clarify the effects of different levels of self-esteem and performance satisfaction on causal internalization of academic performance. Subjects were 162 university students who attributed causality for their individual performances on a midterm examination. Attributions to four internal and four external causal sources were analyzed with a 2 × 2 (Self-Concept × Performance Satisfaction) MANOVA and with follow-up univariate F ratios. Most of the findings support the predictions based on self-esteem theory; i.e., satisfaction with performance, rather than consistency of performance with self-esteem, served as the primary influence on internalization of causality, with students internalizing satisfying outcomes more than dissatisfying outcomes. Cognitive-consistency theory and B. Weiner's (1979, Journal of Educational Psychology, 71, 3–25) attribution proposal regarding maintenance of a stable self-concept also received support, as attributions to the internal and stable causal sources of ability and general effort were a function of an interaction of self-esteem and performance satisfaction. Hence, neither self-theory adequately anticipated the effects of self-esteem and performance satisfaction on causal internalization. Rather, a consolidation of theories is needed to explain the results. 相似文献
355.
356.
How much is an icon worth? 总被引:1,自引:0,他引:1
G R Loftus C A Johnson A P Shimamura 《Journal of experimental psychology. Human perception and performance》1985,11(1):1-13
We report a new technique for assessing the amount of information extracted from the icon that follows a briefly presented picture. The problem of how to measure such information was formulated in terms of how much physical exposure of a picture an icon is worth. Consider two types of stimulus presentations, each with a base duration of d ms. The first is a d-ms picture followed by an icon, and the second is a d + a-ms picture not followed by an icon. How large does a have to be so that equivalent amounts of information are extracted in the two cases? To answer this question, we showed people pictures and later tested their memory for the pictures. We found that the physical exposure duration needed to reach a particular level of performance was approximately 100 ms longer when an icon was not permitted versus when the icon was permitted. This value was independent of the base duration and the luminance of the picture. Moreover, the same value was obtained using three different kinds of memory test and four different sets of pictures. We conclude that an icon is worth approximately 100 ms of additional physical exposure duration. A reasonable explanation for this robust equivalence between icon and stimulus is that the same encoding processes are responsible for extracting information from the icon and from the physical stimulus. Therefore, any variable that affects these encoding processes must affect extraction of information from the icon and the physical stimulus in an identical manner. This prediction was confirmed for one such variable, picture luminance. 相似文献
357.
P J Urcuioli 《Journal of experimental psychology. Animal behavior processes》1985,11(4):502-519
Pigeons were trained on matching-to-sample (MTS) with differential sample-response requirements that were identical with respect to two pairs of sample stimuli but were either correlated or uncorrelated with correct choice. Experiment 1A showed that birds in the uncorrelated condition were slower to reach criterion levels of accuracy than birds in the correlated condition in spite of their equivalent sample discriminations. However, correlated birds were more disrupted in their matching performances than the uncorrelated birds when subsequently switched to nondifferential sample-response requirements (Experiment 1B). Experiment 2 showed that differential sample behaviors also generated higher levels of accuracy on delayed MTS when correlated with choice, and that accuracy in this condition did not differ as a function of whether the samples were hues or lines. Sample dimension did affect memory performance, on the other hand, in the uncorrelated condition. In Experiment 3, reversing differential sample-response requirements for one pair of samples substantially reduced matching accuracy in the correlated group but had almost no effect in the uncorrelated group. These findings demonstrate that differential sample behaviors directly control pigeons' matching performances and also overshadow conditional stimulus control by the samples when these behaviors are predictive of correct choice. The facilitation in matching produced by differential sample behaviors apparently arises from the additional cue these behaviors provide, not because they enhance sample discriminability. 相似文献
358.
In reviewing the literature on the social impact of high school, six themes were identified: (1) students perceive strong norms for conformity to school rules, (2) the emphasis on conformity and control influences the quality of student/teacher relations which tend to be role bound and inflexible, (3) paths to social status continue to emphasize athletic competence, (4) peer group identification has an impact on social relations within the larger community as well as in the school setting, (5) powerlessness is felt as a result of the authoritarian approach to decision making, and (6) the overall high school environment does not enhance students' beliefs in the Bill of Rights. It was concluded that high school students have limited opportunities for flexible self-definition. As a result of the way they are treated by authority figures and the strong pressures toward conformity, many adolescents fail to learn the extent of their rights or effective strategies for the exercise of power. 相似文献
359.
B P Allen 《Adolescence》1987,22(86):271-290
The literature on youth suicide (ages 15-24) is surveyed for the period 1980-1985. Emphasis is placed on general determinants of suicide, predictors in the form of psychological tests, precipitating events (immediate causes), and signs--clues that may signify impending attempts at self-destruction. Suggestions for prevention, and limitations of research on suicide are offered. 相似文献
360.
Keeping juvenile delinquents in school: a prediction model 总被引:1,自引:0,他引:1
The purpose of this study was to test an empirically based prediction model of school dropout on a sample of 137 juvenile delinquents, some who have dropped out and some who have remained in school. The specific factors among the many found in previous research that are salient for predicting whether delinquent youths will drop out or remain in school were determined. An important finding of this study is that it required only four factors to yield a high level of prediction: misbehavior in school, disliking school, the negative influence of peers with respect to dropping out and getting into trouble, and a marginal or weak relationship with parents. The four factors identified create a model that is directly applicable to prevention strategies and is extremely parsimonious. 相似文献