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971.
Data about the lack of synchronism of flexor carpi ulnaris peak EMG values of bimanual reactions during a semantic and during a visuospatial discrimination reaction time task are reported. The effects of type of task as well as the presence or absence of an unexpected stimulus preceding the reaction stimulus on lack of synchronism clearly depend upon the locus of control of the subjects, as measured on Rotter's I-E scale. On the basis of several arguments it is proposed that the measure of lack of synchronism reflects in an opposite sense the amount of dopaminergic activation or motor readiness in the sense in which Pribram and McGuinness in 1975 and Tucker and Williamson in 1984 have defined these concepts. The results for 15 women and 18 men show that more internally oriented subjects are more activated by a semantic task and by an unexpected preparatory stimulus in this type of task than more externally oriented subjects. The opposite appears to hold on the visuospatial task and unexpected preparatory stimuli therein. Together with earlier findings about reaction times and a number of relevant findings in the literature, the results are interpreted as indicative of basic differences in asymmetric tonic activation of the cerebral hemispheres between more internally and more externally oriented subjects. A model is proposed to explain phasic activating effects which ensue when tonically more left- or right-activated subjects perform left- or right-hemisphere tasks and when supplementary irrelevant stimuli are received. 相似文献
972.
We have examined the human ability to determine the direction of movement of a variety of plaid patterns. The plaids were composed of two orthogonal sine-wave gratings. When the plaid components are of unequal spatial frequency or sometimes of unequal contrast, observers judge the direction of movement incorrectly. In terms of the two-stage model of Adelson and Movshon (1982), these errors may result from either a misjudgment in the perceived speeds of each of the components or a failure in the combination of one-dimensional component movements into a coherent direction of motion of the two-dimensional plaid pattern, or both. A comparison of the perceived direction of motion of plaids with the relative perceived speeds of the plaid component gratings suggest that both failures occur, but in different circumstances. The relative perceived speed of the plaid components was measured with a spatial and a temporal forced-choice technique, the former leading to larger differences. Our results support the notion that the visual system decomposes a moving plaid into oriented components and subsequently recombines the component motions. 相似文献
973.
974.
Monique Lortie-Lussier Suzanne Simond Natalie Rinfret Joseph De Koninck 《Sex roles》1992,26(3-4):79-96
The question addressed is: do recent changes in the occupational roles of women, with their indirect influence on men's lives, have an impact on the dreams of women and men? Three groups of parents (N=96) including in equal numbers, mothers at home, wage-earning mothers and fathers, kept a dream diary from which two dreams per dreamer were content analyzed. Assuming continuity between daytime and dream experiences, it was hypothesized that differences in manifest dream content would be a function of single versus dual role enactment, rather than sex. Contrary to predictions, statistical analyses performed on selected dream variables did not yield significant differences between groups for pleasant and unpleasant emotions, friendly interactions and aggression. Dream characters, and the concerns they reflect, were found to vary, though, according to social roles. Commitment to their family was reflected above all in the mothers' at home dreams, while commitment to their profession took precedence in those of the wage-earning mothers. Comparable commitment to work and family was found among the fathers. Findings suggest that as gender differences in waking life decrease, so may differences in dreams. 相似文献
975.
Self-regulation and Computer-aided Instruction 总被引:1,自引:0,他引:1
976.
Abstract –How often should one check on a system that is at risk for some malfunction? The optimal interval between inspections depends on the likelihood of malfunction, the cost of inspection, and the cost of treatment We develop a mathematical expression for the optimal inspection interval as a function of these parameters and then an approximation for that expression The approximation indicates that as the risk increases or the ratio of inspection to disease cost decreases by a factor of n, the inspection interval should be reduced by n1/2 We also report an experiment indicating that subjects who generate optimal inspection intervals use examples as anchors and then perform adjustments for variations in risk and cost factors However, they do not approximate the appropriate square-root adjustment rule The observed anchor-and-adjust process suggests that normative recommendations may serve as influential benchmarks, even if they are not adhered to directly. 相似文献
977.
Twelve married obsessive-compulsive patients were randomly allocated to either selfcontrolled exposure or partner-assisted exposure. Treatment in both conditions consisted of homepactice.The results at the Post-test showed that both versions of exposure in vivo resulted in significant improvements but the partner-assisted group improved more. After a 1-month treatment-free period no significant differences between conditions were found due to a continuing improvement in the selfcontrolled exposure condition. Results were maintained at a 6-month follow-up.It was concluded that home-practice is a cost-effective treatment procedure for obsessive-compulsives and that couple training may be useful with selected patients. 相似文献
978.
In most of the effective techniques for reducing fear, exposure to the fear-provoking stimulus is a prominent feature. It is argued that in many circumstances, engaged exposure to the fear stimuli is a sufficient condition for fear-reduction, but there is no good reason for supposing that such exposure is a necessary condition for fear-reduction. Seven examples of fear-reduction apparently taking place in the absence of exposure are used to illustrate the argument. Some theoretical and practical consequences of the argument are introduced. 相似文献
979.
980.
We have analyzed the verbal and spatial performances of 141 left-handed and 130 right-handed patients having unilateral hemispheric lesions and that have been grouped according to whether familial sinistrality (FS) is present or not. The present results confirm those of previous studies establishing a relation between FS on one hand and the ambilaterality of the functional representations of language and the lesser intrahemispheric focalization on the other. Such a relation has not only been found with left-handers but, to a lesser extent, with right-handers as well. On the contrary, this type of hemispheric organization does not prevail with respect to spatial functions. These results also allow for the exclusion of any relation between the strength of left-handedness and the pattern of cerebral organization. One finds, nevertheless, some indications that favor the influence of sex on cerebral organization, although it is impossible to specify the interference of this factor. 相似文献