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281.
282.
A longitudinal design was employed to test the main and stress-moderating effects of young adolescents' perceived family environment (Family Environment Scales; FES; Moos & Moos, 1981) on their depression, anxiety, and self-esteem. This study was part of a larger longitudinal project (L. Cohen, Burt, & Bjorck, 1987) that demonstrated the significant cross-sectional effects of the young adolescents' controllable and uncontrollable negative events, and the significant longitudinal effects of the former. The present cross-sectional analyses demonstrated the hypothesized main effects of the FES scores; families perceived as cohesive, organized, and expressive were related to positive psychological functioning, whereas families perceived as conflict-ridden and controlling were related to negative functioning. However, in general these effects were nonsignificant in the longitudinal analyses. Although there were a number of significant Negative Events x FES interactions, in no instance did the pattern support the hypothesized stress-buffering role of positive family climate.  相似文献   
283.
Survey respondents may inaccurately report mental health service utilization for motivational and cognitive reasons. There is little evidence on accuracy of self-reports of mental health service use, and this evidence suggests that respondents tend to underreport inpatient utilization. This study addressed the question of self-report accuracy by comparing survey data from a large probability sample to data from computerized records of publicly funded mental health services. Few inaccuracies in self-reporting were detected. However, despite the use of data bases that were unusually appropriate for verifying self-reports, several problems limited the feasibility of validation. Suggestions are offered for increasing the feasibility of validation in future studies.  相似文献   
284.
In recent years in research on intergroup relationships, the assumption has increasingly been made that discrimination dominates decisions when individuals allocate resources between (members of) own and other group. Conversely, in empirical studies of interpersonal decision-making, including an extensive literature on the development of children's allocation rules within dyadic relationships, it has been repeatedly observed that in dyadic relationships choices though responsive to various changes in the environment, are more strongly governed by fairness rules. The present research extends the interpersonal fairness paradigm to the intergroup case, and examines the effects of some of those variables, namely, children's age, input and attitudes toward other, that have been observed to influence choice behaviour within interpersonal relationships. The findings indicate that as children are socialized, fairness rules also play an increasing dominant role in intergroup allocation decisions, and that both relative input and the language of the outgroup influence such decisions. At the same time, there is some preliminary evidence to indicate that the relative strength of self-interest may be somewhat stronger in intergroup than in interpersonal relationships. Finally, a number of the issues that must be confronted in comparing the two more important forms of human social choices, interpersonal and intergroup decision-making, are considered.  相似文献   
285.
Processing resources and age differences in working memory   总被引:1,自引:0,他引:1  
This study investigated the performance of young and old subjects on a modified version of the working memory task developed by Baddeley and Hitch (1974). Subjects were required to verify a set of sentences of varying complexity while they repeated aloud zero, two, or four words. The older subjects took longer to verify the sentences, especially when the sentences were grammatically complex, but the effect of concurrent memory load on verification latency was the same in both groups. These results cast doubt on the notion that there is an age-related decline in one general pool of processing resources. They also suggest that older people have greater difficulty with the active processing aspects, rather than with the passive holding aspects, of working memory tasks.  相似文献   
286.
Hindsight bias: An interaction of automatic and motivational factors?   总被引:1,自引:0,他引:1  
If subjects are asked to recollect a former response after having been informed about the correct response, their recollection tends to approach the correct response. This effect has been termedhindsight bias. We studied hindsight bias in an experiment requiring numerical responses to almanac-type questions for physical quantities. We varied (1) the time at which the correct information was provided, (2) the encoding of the original responses by asking/not asking subjects to give a reason for the respective response, and (3) the motivation to recall correctly. We found that hindsight is less biased if reasons are given and if the correct information is provided at an earlier time. Motivation had only interactive effects: (1) With high motivation to recall correctly, the time the correct information was provided had no influence. (2) With reasons given, the variation of motivation showed no effect. These results rule out purely motivational and purely automatic explanations.  相似文献   
287.
Speakers in informal conversations tend to alternate regularly between lower and higher amounts of talking; the periods of these low/high activity cycles are on the order of 3, 6, and 15 minutes. Statistically significant periodicities occurred in 55% of the conversations studied. The periodograms that describe the partition of variance among periodic components whow consistent individual differences in the cyclic patterning of vocal activity. Discriminant analysis used the amount of variance accounted for by each of the 12 lowest-frequency periodic components as discriminating variables to see whether speakers could be identified on the basis of the cyclic patterns in vocal activity. Speakers were discriminated and classified at levels well above chance. This suggests that there are consistent individual differences among speakers in the length of cycles in amount of talk.We gratefully acknowledge support from the Central University Research Fund and from the office of the Dean of Liberal Arts at the University of New Hampshire.  相似文献   
288.
The perception of an optical flow projected on the ground surface   总被引:3,自引:0,他引:3  
In most experiments in which the importance of visual control on postural stability is studied, optical stimuli attached to vertical surfaces are used. Analyses of long-term standing readjustments generally involve back-and-forth movements of a visual scene or its projection on vertical circular screens. In a natural environment, however, visual information is largely available from the ground. The aim of the experiment reported was to assess the effect of a flow pattern simulating an open outdoor setting on motion perception and postural control. Subjects were presented with an optical texture projected onto the ground. Periods of motionless texture alternated with equivalent durations of unidirectional flows. The change of position of the subject's centre of gravity over time was recorded on a force platform. Results show that the direction of body sway corresponded with that of texture motion. Important aftereffects, as shown in linear vection experiments, were also observed. However, the latency of postural responses was much shorter than with prolonged unidirectional flows produced in other locations of the visual environment. The hypothesis of an ecological specificity of the flows perceived on the ground during terrestrial displacements is discussed.  相似文献   
289.
Orientation discrimination and cortical function in the human newborn   总被引:1,自引:0,他引:1  
A Slater  V Morison  M Somers 《Perception》1988,17(5):597-602
There is some controversy concerning whether or not the visual abilities of the newborn are mediated entirely through subcortical pathways or whether the visual cortex is functioning at birth. A critical test of cortical functioning is discrimination of orientation: orientation-selective neurons are found in the visual cortex but not in subcortical parts of the visual system. An experiment is described in which newborn infants were habituated to a square-wave grating oriented 45 degrees from vertical. After habituation, significant preferences for the novel, mirror-image, grating were found, a result which argues for some degree of visual cortical functioning at birth.  相似文献   
290.
This study was designed to evaluate the possibility that a pattern of cognitive deficit is associated with delinquent behavior, while avoiding some of the methodological problems of previous research. The Self- Report Early Delinquency instrument and a research battery of neuropsychological tests were administered blindly to an unselected cohort of 678 13- year- olds. Because the diagnosis of attention deficit disorder (ADD) was found at markedly elevated rates in the backgrounds of these delinquents, the possibility was examined that the neuropsychological deficits of delinquents might be limited to delinquents with histories of ADD. Although delinquents with past ADD were more cognitively impaired than non-ADD delinquents, both groups scored significantly below nondelinquents on verbal, visuospatial, and visualmotor integration skills. In addition, ADD delinquents scored poorly on memory abilities. Subjects with ADD who had not developed delinquent behavior were not as cognitively impaired as ADD delinquents, suggesting that it is the specific comorbidity of ADD and delinquency that bears neuropsychological study.This work was supported by USPHS Grant 1 R23 MH-42723-01 from the Antisocial and Violent Behavior Branch of the National Institute of Mental Health. The Dunedin Multidisciplinary Health and Development Research Unit is supported by the Medical Research Council of New Zealand. Appreciation is expressed for the methodological advice of Prof. Sarnoff A. Mednick, and for the data collection efforts of Mrs. Pat Brasch, Mrs. Kathleen Campbell, Mr. Rich Poulton, and the psychometrists who administered the WISC-R.  相似文献   
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