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51.
Two versions of a distributed-memory model, one for associative information and one for serial-order information, leave open the question of whether there are two different modes of operation or only one. An analysis of these two versions showed that differential predictions emerge when one considers the role of item information. To test these predictions, a standard item-recognition task (Sternberg, 1966) was embedded in a paired-associate probe-recognition task, a serial-order probe-recognition task, or both. The item-recognition serial-position curves were quite different in the paired-associate and the serial-order conditions, and followed the paired-associate condition when the two were combined. In general, the results were consistent with the predictions of the distributed-memory models, and supported the idea of different modes of operation rather than a single common mode of operation. 相似文献
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This article presents a series of studies investigating the influence of experimental factors and the personological variables of age and sex upon spatial abilities. It was hypothesized that the overall equivocal findings typical of spatial research may be partially due to the use of different factors across studies. The experimental variables of spatial factor, task demands, spatial information type, information-processing mode, and response mode were systematically manipulated across the eight studies. In each individual analysis of data collected in a specific study, no significant main effect sex differences were detected. However, when a meta-analytic review of the studies was conducted, both spatial information dimensionality and information dimensionality × spatial factor assessed proved to be influential on male and female spatial performances. Female performance was superior when the dimensionality of stimulus and response variables was invariant. Males had the advantage when dimensionality crossing was necessitated. The discrepancy between the sexes was particularly dramatic when the spatial orientation factor was tapped. 相似文献
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Kinetic subjective contours 总被引:2,自引:0,他引:2
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Sarah B. Woods Angela Hiefner Patricia N. E. Roberson Nida Zahra Elizabeth Mayfield Arnold Victoria Udezi 《Family process》2023,62(1):230-253
African Americans are at significantly greater risk of hypertension and worse cardiovascular outcomes than other racialized groups, yet hypertension intervention effects remain limited. Thus, it is necessary to understand the potential mechanisms whereby interventions may be more effectively targeted to improve health. Supported by prior research evidence and guided by the Biobehavioral Family Model, this study examined associations between family relationship quality, psychological wellbeing, and self-management behaviors for African Americans with hypertension. Data were pooled from three Midlife Development in the U.S. projects, resulting in a sample of 317 African Americans (63.4% female, Mage = 53.32) with self-reported high blood pressure in the past 12 months. We tested four cross-sectional multiple mediator models, with depressed mood and environmental mastery mediating associations between family strain and exercise, smoking, problematic alcohol use, and stress-eating. Environmental mastery mediated the association between greater family strain and decreased odds of achieving recommended exercise levels; greater odds of reporting problematic alcohol use; and greater stress-eating. Though family strain was associated with depressed mood in each model, this variable did not serve as an indirect pathway to self-management behaviors. Family strain, and the potential pathway identified via environmental mastery, may be a meaningful predictor of disease self-management for African Americans with hypertension. Longitudinal studies are needed to examine directionality and to support intervention trials for improving self-management and hypertension outcomes. 相似文献
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Patricia M. Blough 《Attention, perception & psychophysics》1972,12(4):342-348
This three-part study describes wavelength generalization gradients around a series of training wavelengths ranging from 480 to 645 om. Luminance was controlled for the pigeon’s spectral sensitivity. The response measure was probability of keypecking during a 2-sec stimulus presentation. Both an extinction procedure, where stimulus wavelengths occurred in 15-nm steps, and a maintained discrimination procedure, where step size was 2 to 4 nm, were used to obtain gradients. During a portion of the maintained discrimination procedure, new luminances were introduced, so that the effect of luminance level on gradient slope could be examined. Comparison of the resulting functions across training wavelengths revealed: (1) consistent differences in gradient slope in different spectral regions and (2) an increase in slope with luminance increase. The findings are related to recent electroretinographic wavelength contrast data and to psychophysical measures of wavelength discriminability. 相似文献
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Bernard P. Cohen 《Synthese》1972,24(3-4):401-409