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991.
992.
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   
993.
Duration of visible persistence in relation to range of spatial frequencies   总被引:1,自引:0,他引:1  
Five experiments examined the relationship between range of spatial frequencies contained in a visual display and duration of visible persistence. The high spatial frequency contents of the display were reduced by defocusing the image at the retina. Duration of visible persistence was measured by a task that required perceptual integration of a pattern whose parts were displayed sequentially in time. Experiments 1 and 2 showed that progressive reductions in the high-frequency contents of the display produced corresponding decrements in the duration of visible persistence. Experiments 3, 4, 5 showed that decrements in the duration of visible persistence could not be attributed to changes in the apparent size or in the brightness of the display brought about by defocusing. The results were interpreted in terms of the temporal response properties of perceptual mechanisms attuned to separate ranges of spatial frequencies. Strong parallels were drawn with the multichannel theory of visual information processing proposed by Breitmeyer and Ganz.  相似文献   
994.
Two experiments are reported that tested the effects of crawling-onset age, the amount of crawling experience, and testing age on avoidance of the deep side of a visual cliff apparatus by human infants. In Experiment 1, 49 infants ranging in age from 7 to 13 mo. were tested on the visual cliff after 1 or 2 mo. of crawling experience. Discriminant analysis revealed that crawling-onset age, and not crawling experience, discriminated between those infants who crossed and those infants who avoided the apparent drop-off. Infants who crossed the deep side were infants with an early crawling-onset age. In Experiment 2, 40 infants were tested on a visual cliff apparatus, half at 9 and half at 12 mo. of age. Discriminant analysis again found that crawling-onset age discriminated between infants who crossed the infants who would not cross the deep side, whereas testing age alone did not. These results call into question the idea that experience crawling is critical in inducing visually guided avoidance behavior in infants. It is argued that the crawling-onset age effect occurs because crawling during the tactile phase of infancy interferes with later visual control of locomotion.  相似文献   
995.
While considerable research has investigated the relationship of sex and/or sex role to general or trait anxiety, little is known about their relationship to more specific anxiety types. Based on the postulate that sex and sex-role differences may depend on the extent to which an anxiety-producing situation represents a sex-stereotypic domain, the present study compared their relationships to four measures of anxiety: Math anxiety, test anxiety, and two measures of trait anxiety. Subjects were 180 undergraduate students enrolled in introductory psychology courses. Although females reported higher levels of anxiety on all four scales than did males, a discriminant function analysis indicated that math anxiety was the strongest contributor to the separation of the sexes. Significant score differences as a function of sex role were found using the STAI A-Trait scale, and a significant sex × sex-role interaction was found for scores on the S-R Inventory of Anxiousness. Feminine-typed males and undifferentiated females reported highest anxiety levels in comparison to same-sex individuals. Implications for the understanding and treatment of both general and situationally specific anxiety are discussed.  相似文献   
996.
Analysis of the spontaneous speech of eight stuttering and eight normally fluent children reveals that (a) the location of both stuttering and normal disfluent moments is constrained by sentential constituent structure, and (b) stuttering children experience fluency breakdown with a particular type of constituent (verb phrase) not usually disfluently produced by normals. A view of early stuttering as a sentence planning and integration disorder is present.  相似文献   
997.
The present research studied the relationships between assertive behavior and two personality variables: extroversion and need for approval (nApp). Assertive behavior was measured in two role-play situations: an authority situation and an equal situation. It was found that extroverts behaved more assertively than introverts. nApp was negatively related to assertive behavior for females, while for males no correlation was found between nApp and assertive behavior in the authority situation and a positive correlation was found in the equal situation. It was concluded that extroversion and nApp are contributing factors in assertive behavior and that nApp moderates assertiveness differentially for males and females.  相似文献   
998.
This article examines one approach to helping counselor trainees and clients gain insight into the death and dying process and its stages, and supports the use of literature as a counseling tool for helping clients confronted with the death or dying experience.  相似文献   
999.
This article takes as its point of departure the enrollment in U.S. colleges of many highly skilled athletes who are severely lacking academically, and argues that remedial success could be maximized if practitioners in developmental studies programs better understand the unique psychosocial dimensions of the student athlete.  相似文献   
1000.
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