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961.
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   
962.
Rats were used to determine whether stress-induced analgesia (SIA) can be produced by conditioning with interoceptive stimuli (LiCl) as with exteroceptive stimuli (footshock). SIA was measured using a tail-flick test. As expected, unavoidable footshock as well as conditioning with footshock produced SIA. In contrast, conditioning with LiCl failed to cause SIA. The findings support the notion of functional differences in neural substrates for conditioning by exteroceptive and interoceptive cue.  相似文献   
963.
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   
964.
Male rats isolated for 60 days in adulthood spent less time investigating odors of females and urine-marked less over these odors than did males kept in groups of three. Isolated males did not differ from grouped males in their responses to odors of unfamiliar males or their own odors. After social experience the isolated males showed an increase in urine-marking but no change in odor preferences. Individual housing therefore appears to alter olfactory communication in the same way that it does other social behaviors and these changes may be mediated by the same mechanisms.  相似文献   
965.
966.
This article reviews cognitive-behavioral assessment principles and procedures. The functions of such assessments are noted, and issues and advances in cognitive assessment are discussed. The need for integrated cognitive, behavioral, and affective assessments is then explored. Finally, conceptual methodological, and clinical issues in the integration of assessments and study of reciprocal determinants are presented.Preparation of this paper was supported in part by a General Research Board Faculty Research Award from the University of Maryland. The author would like to thank Steve Graham, Donald Meichenbaum, Barbara Keogh, and Bernice Wong for their feedback during the preparation of this paper.  相似文献   
967.
968.
It is argued that stable, individual differences in helping behavior have not generally been observed in previous research because of the type of helping studied. This paper advocates the study of planned helping behavior as opposed to spontaneous helping behavior. The results of three studies are reported. In Study 1, an instrument designed to measure level of involvement in planned helping activities was developed. Scores on this instrument were found to be stable over a 7-month period. Further analysis revealed two major types of planned helping: (a) formal, organizational helping and (b) informal helping between friends and family. Study 2 examined a variety of intrapsychic and demographic correlates of formal and informal planned helping. Study 3 found support for the hypothesis that people in helping professions have higher levels of involvement in everyday planned helping than do people in nonhelping occupations. It is concluded that the study of planned helping, although posing methodological difficulties, is a necessary adjunct to experimental research.  相似文献   
969.
We used a constrained classification task to examine the perceptual relations between global and local levels in hierarchical patterns composed of many, relatively small elements and those composed of few, relatively large elements. In Experiments 1 and 3 subjects were asked to make classifications based on "form" or "texture." In Experiments 2 and 4 they were asked to classify according to the "shape" of the configuration or the elements. The results indicate that configural and elemental levels are perceptually separable for many-element patterns when processed as form and texture: Subjects could attend to either level without being affected by variation along the irrelevant dimension. However, when the same many-element patterns were processed for global and local shape, subjects could not selectively attend to either level. For few-element patterns, global configuration and local elements appeared to be perceptually integral dimensions. These results are relevant to two issues: the global precedence hypothesis and the explanations of integral and separable dimensions.  相似文献   
970.
Two alternative conceptualizations of selective adaptation with speech have recently received attention. The adaptation level theory (AL) outlined by Diehl (1981) and a two-stage model outlined by Sawusch and Jusczyk (1981) can both account for much of the adaptation and paired-comparison data. Recently, Diehl, Kluender, and Parker (1985) proposed that all adaptation and contrast data can be accounted for by AL theory. They reported the results of a study that showed evidence of streaming in selective adaptation and claimed that their results provide a counterdemonstration to recent studies that have argued against the AL approach. In the present article, an outline of how the Diehl et al. results can be accounted for by both the two-stage model and AL theory is presented. In addition, a new set of results comparing adaptation and paired-comparison procedures is presented. These results are precisely as predicted by the two-stage model, but they can not be handled by AL theory.  相似文献   
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