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831.
Gender differences across age in motor performance a meta-analysis   总被引:3,自引:0,他引:3  
  相似文献   
832.
Deficient processing theories of the spacing effect attribute poor recall of massed-repeated items to a failure to process one or both of the presentations fully. An implication of this approach is that anything that increases the probability that a repetition will receive full processing, or conversely, anything that decreases the probability that the item will be recognized as a repetition, should improve memorability of the item. The present set of experiments tested this prediction by manipulating the surface structure of repeated sentences. On the basis of previous research, it was assumed that memory for surface structure of sentences decays rapidly, and hence can contribute to initial identification of repetitions only at short spacings. Because this manipulation should hinder recognition of repetitions as repetitions, it was expected to induce full processing of massed repetitions, and thus facilitate recall of these items. This prediction was supported. When sentences were repeated verbatim (Experiment 1) or by the same speaker (Experiment 2), the typical spacing effect was obtained. However, when the surface structure or speaker changed at time of repetition, massed repetitions were recalled nearly as well (Experiment 1) or as well (Experiment 2) as their spaced counterparts.  相似文献   
833.
The intent of the study was to examine the effects of parental (mother and father) and child (gender and communicative status) status variables on the teaching strategies used by parents in a paper-folding task. The linguistic and nonverbal strategies of 120 parent-child groupings were analyzed during paper-folding tasks. Parents' strategies were coded according cognitive demand and directiveness. Results indicated that strategies varied as a function of children's communicative status. Parents were less directive and more demanding of nonhandicapped children compared to handicapped children. Parents' strategies seemed to be determined by children's ability to sustain discourse. Results are discussed in terms of Vygotsky's notion of the zone of proximal development.This research was partially supported by a grant from the U.S. Office of Education, Office of Special Education (Grant No. G007902000) to I. Sigel and A. McGillicuddy-DeLisi at Educational Testing Service, Princeton, and from the Biomedical Research Support Grant Program, Division of Research Resources, N.I.H. (Grant No. BRSG 507RR07025-17) to the first two authors. We acknowledge the helpful comments of two anonymous reviewers.  相似文献   
834.
This study examined two issues related to the use of nonprofessional counselors (n = 159) within the context of a diversion program for juvenile offenders. First, the relationship of the nonprofessionals' personality traits and general attitudes to client outcome was examined. No statistically significant correlations were observed. Second, the differential impact of various training and supervision factors was examined in terms of nonprofessional satisfaction, attitudes, and locus of control. Results suggested that training intensity, training content, and supervision setting may influence nonprofessionals' attitudes towards various social groups and their satisfaction with the nonprofessional experience.  相似文献   
835.
The relationship of characteristics of the social environment to the adaptation of adolescents from high-risk predisposing environments was examined. Specifically, the degree to which adolescents' perceptions of various dimensions of their family and school environment as well as sources of social support related to differential levels of personal well-being and academic adjustment was explored. Multiple regression analyses revealed differences in the salience of the dimensions of the social environment as a function of the particular sphere of functioning under consideration. Implications of the findings for developing a model for understanding the relative vulnerability of individuals at risk as well as of the design of preventive interventions are discussed.  相似文献   
836.
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   
837.
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   
838.
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   
839.
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   
840.
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   
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