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881.
In previous studies, it has been demonstrated that visible persistence--the period for which the perceived duration of a stimulus exceeds its physical duration--can be extended by briefly incrementing the luminance of the stimulus immediately prior to offset. Using a two-component pattern integration task, we show that this effect is not an artifact of change in the total luminous flux within the stimulus. Visible persistence was unaffected by overall luminance of the stimulus. It was also time-locked to the luminance increment. Visible persistence is seen to result from a process that is initiated by stimulus onset and that can be either wholly or partially reinitiated by the onset of the luminance increment. The duration of this process (which determines the duration of stimulus visibility) can be modified in a graded fashion by stimulus events that occur after its initiation. We outline a single-process inhibitory feedback model of the persistence mechanism that accounts for the present findings.  相似文献   
882.
A study of 79 female college students examined the reliability and validity of two new size/weight-related measures of body image. The Body-size Appraisal Scale and the Overweight Preoccupation Scale were derived from existing instruments. Analyses supported the internal consistency and 2-wk. test-retest reliability of both new scales. Correlations of scores on each scale with measures of anxiety about being fat, negative body-image affect and avoidance, restrained and bulimic eating, and depression support their concurrent and construct validity. Scores on the Overweight Preoccupation Scale were also related to the extent of investment in physical appearance. Regression analyses indicated that each new scale could be predicted from several other conceptually relevant body-image attitudes, even after actual body weight was controlled.  相似文献   
883.
A group of 39 female and 15 male undergraduate students took part in a study of the relationship between perceived violence of criminal offenders and interpersonal distance preferred by nonoffenders. Preferred interpersonal distance, measured for subjects informed that the person with whom they would be sitting in a room was either a violent offender, nonviolent offender, or nonoffender, was the number of seats subjects chose to sit from the person. Analysis of variance shows subjects preferred significantly less mean distance in the nonoffender condition versus either the nonviolent or violent offender conditions.  相似文献   
884.

Articles

Interview with Dr. Peter Rutter, author ofSex in the Forbidden Zone, July 27, 1990  相似文献   
885.
A resource dependency framework (Pfeffer & Salancik, 1978) is applied to general manager (GM) selection decisions. Hypotheses are developed predicting associations between organizational contextual features (environmental instability, strategy, organizational performance, size) and background characteristics of GMs selected to head business units (organizational familiarity, functional experience, age). Data were collected on 40 recent GM selection decisions. Findings indicate that organizational contextual features influence the type of GM selected. Key results are that industry instability, organizational strategy, and organizational size were associated with GMs'organizational familiarity (i.e., tenure levels), and that organizational strategy was associated with the age of selected GMs. This study provides support for the application of a contingency perspective to human resource management.  相似文献   
886.

Treatment of rats with the potent antiaggressive compound eltoprazine hydrochloride (1.0 & 2.0 mg/kg) slowed both predatory attack and killing of frogs. These results demonstrate a specific predation-inhibiting action of the drug which is not obscured by the elements of conspecific aggression seen during muricide. Unlike the closely related compound fluprazine, eltoprazine increased both attack and kill latencies implying that the effects of the two drugs on predation are mediated by at least somewhat distinct drug actions. It is further suggested that eltoprazine may be more specifically antiaggressive in its actions than related phenylpiperazine compounds.

  相似文献   
887.
319 3rd and 5th grade children were asked to rate their parents' job satisfaction. These ratings were compared to parents' self-reports of job satisfaction. Older children were more accurate in their estimates. Girls were more accurate in rating their mothers, while boys were more accurate in rating fathers. Children who perceived their parents as satisfied with their jobs were more likely to aspire to their parents' occupations than those who rated their parents less satisfied.  相似文献   
888.
Effect of boredom proneness on time perception   总被引:1,自引:0,他引:1  
As part of a larger study examining attribution differences in boredom, the effect of Boredom Proneness on perception of time passage was investigated in 110 undergraduates completing a tedious number-circling task. Highly boredom-prone individuals perceived time as passing more slowly during the task than low boredom-prone persons, but the two groups did not differ in their objective or chronometric time-passage estimates. The findings support the contention that depressed affect produces a subjective slowing of time but does not alter the perception of objective passage of chronometric time.  相似文献   
889.
Considers a preventive intervention effort designed to modify the characteristics and regularities of the school environment so as to enhance the expectations conveyed to high risk students. Employing this case effort (Weinstein et al., 1991) as a base, several issues are highlighted that deserve greater attention in the design, implementation, assessment, and reporting of other preventively-focused social interventions. These issues include: (1) the degree of program implementation fidelity, (2) the impact a lack of attainment of program fidelity may have on arriving at erroneous evaluation conclusions about social programs, (3) the ways in which the theory and basic research employed in the program rationale is appropriate to and reflected in the program as designed, (4) issues of program potency and dosage, (5) the ways in which quantitative and qualitative evaluation data can enhance each other, and (6) the import of evaluability assessments of programs prior to moving to outcome evaluations. In addressing these issues, the importance of developmentally- and ecologically-informed program formulations is underscored. Finally, the critical role that program reports such as the Weinstein paper, with its careful discussion of both the process of implementation and outcome assessments, can play in the development of more effective prevention program implementation efforts is highlighted.  相似文献   
890.
In this study of auditory prestimulation cues, picture naming performances under phonemic and semantic conditions were compared to picture naming performance under a neutral condition. Twenty aphasic subjects named 324 pictures (108 pictures x 3 conditions) each. Responses were scored using a coding system adapted by the investigator from classification systems used by Williams and Canter (1982) and Kohn and Goodglass (1985). Results indicated that naming accuracy was facilitated by phonemic and semantic cues. An examination of the distribution of errors under the three conditions revealed systematic effects of phonemic and semantic cues on the frequency of occurrence of specific error types. Increases in semantic paraphasia proportion scores and decreases in unrelated word error proportion scores were associated with the semantic condition, while increases in phonemic paraphasia proportion scores were associated with the phonemic condition. The finding that naming performance of aphasic adults varies as a function of the type of information provided by the cue is discussed in relation to cascade visual confrontation naming models.  相似文献   
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