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71.
72.
The perception of control may be established if an individual is provided with an opportunity to choose and if the outcome of the choice is moderately uncertain. In turn, perceived control has been shown to enhance motivation and performance. In the present experiment, the effects of uncertainty about environmental control were examined by measuring the speed with which choices were made. When control was implicitly provided, decision latencies were shorter than when control was either explicitly available or not available at all. Paradoxically, providing information about control may reduce uncertainty and thereby diminish the perception of control. The contribution of control and choice to the development of perceived control is discussed.This research is based on a thesis by the first author submitted in partial fulfillment of the master of science degree at Virginia Polytechnic Institute and State University and was supported by a grant from the U.S. Army Research Office to the second author.  相似文献   
73.
The Ramey and Haskins intervention experiment succeeded in producing IQ gains at three years of age averaging about one standard deviation in young children who were selected for being at risk for subnormal intellectual development. The study is examined in terms of its consistency with other findings, the heritability of IQ, the g aspect of IQ, the simplex pattern of longitudinal interage mental test score correlations, mother-child IQ correlations, and criteria for establishing educationally and socially significant gains in intelligence defined as g rather than as a score on a particular test. Narrow transfer of training from cognitive intervention techniques to IQ test performance in early childhood, rather than enhancement of the g factor itself, is hypothesized as a cause of the typical fadeout of early IQ gains in later childhood.  相似文献   
74.
Duplex perception, a phenomenon previously demonstrated for speech stimuli, is demonstrated here for musical stimuli. In the first experiment, major and minor chords are produced by dichotic fusion of two simultaneous piano notes presented to one ear (perfect fifth) with a “natural” or “flat” single note presented to the opposite ear. Musically trained subjects perceive simultaneously both the single tone and a fused (major or minor) chord. The chords are labeled more consistently than the single notes, even though the fused chords differ solely in terms of the contralateral notes. In a second experiment, using pure tones in place of piano notes, other musically trained subjects individually exhibited categorical perception for either the fused chord or the single tones, but never for both types of stimuli. The duplex phenomenon is discussed in terms of its implications for its specific component modes of perception.  相似文献   
75.
A questionnaire was constructed to measure individual differences in pretrial bias among jurors. The final Likert scale, called the Juror Bias Scale (JBS), contains 17 items—8 that reflect pretrial expectancies that defendants, in general, commit the crimes with which they are charged and 9 that reflect the value attached to conviction and punishment. The scale is internally consistent and test-retest reliable. Scores are uncorrelated with social desirability, moderately correlated with I-E control and belief in a just world, and more highly correlated with authoritarianism. In one validation experiment, student jurors were exposed to three trial presentations in a laboratory setting. Overall, subjects classified as prosecution biased were more conviction prone and adopted a less stringent standard of reasonable doubt. In a second study, community jurors watched one of two videotaped mock trials in a courtroom. Prosecution-biased subjects asserted a higher probability that the defendent committed the crime and rendered a higher percentage of guilty verdicts than defense-biased subjects for one of the two trials. JBS scores were unrelated to all demographic variables, but were significantly correlated with political views. The potential uses and limitations of the JBS are discussed.  相似文献   
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Evoked-potential measurements can readily be implemented on a microcomputer. We present as an example a system for obtaining an evoked-potential augmenting/reducing measure using the Apple II microcomputer. Specialized features of the PASCAL program and peripheral equipment are described.  相似文献   
78.
It has been proposed that control over the environment increases the perception of control, thereby enhancing motivation. Revesman and Perlmuter (1981) found that when subjects were permitted to choose response terms to be learned on a paired-associate task, decision latencies were faster if the announcement of the desired option caused the screen upon which materials were printed to go blank. On the basis of the results of the present experiment, it was concluded that control of the environment does result in faster decision latencies, but that this effect occurs despite a decrease in the perception of control.  相似文献   
79.
In order to characterize more completely the nature of the frontal lobe-type cognitive changes in patients with dominantly inherited olivopontocerebellar atrophy (OPCA) we administered two tasks sensitive to frontal system dysfunction, delayed alternation (DA) and delayed response (DR), to 12 patients from one OPCA family. Affected members from this family have previously been shown to have a marked and widespread cerebral (including frontal) cortical cholinergic reduction as severe as that observed in Alzheimer's disease. Performance on DA, but not on DR, was significantly impaired in the OPCA patients compared to that in the controls. We suggest that the DA deficits in OPCA could be a consequence of a loss of cholinergic innervation to orbitofrontal or possibly temporal cortical areas and/or damage to the integrity of the cerebello-frontal neuronal connections.  相似文献   
80.
Changes in depressive-symptom experiences over a 5-year period were investigated in a community sample of 251 women between the ages of 51 and 92 years. Findings from a confirmatory factor analysis of the SCL-90-R Depression and Additional Symptoms scales (Derogatis, 1983) indicate that two phenomenally different syndromes underlie symptom-reporting patterns. A depressive syndrome, more classic in form, shows decreasing levels with increasing age, although a depletion syndrome, marked by feelings of enervation and a loss of interest in things, shows increasing levels with advancing age. The relative independence of the two syndromes, as well as their differing relations to four more delimited forms of distress that were identified in the analyses, have important implications for future research on the age-depression relation.  相似文献   
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