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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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The effects of unavoidable shocks on a multiple schedule having an avoidance component 总被引:1,自引:1,他引:0
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Marcus B. Waller Patricia F. Waller 《Journal of the experimental analysis of behavior》1963,6(1):29-37
Two dogs were maintained on a multiple schedule having both a food reinforced and an avoidance component (Mult VI 1′ SΔ AvoidSS20 RS20 SΔ). The effects of superimposing an Estes-Skinner procedure for delivering unavoidable shocks on all components of the multiple schedule were observed. The buzzer-shock pairing of the Estes-Skinner procedure produced an increased rate of responding on the avoidance component of the schedule and also on the SΔ components. No persistent change in rate was observed on the food component during the pre-shock stimulus. Control performances on all components could be regained by either extinguishing or eliminating the buzzer-shock pairing. Extinction of the avoidance responding had little effect on the increased rates of responding produced by the Estes-Skinner procedure on the SΔ and avoidance extinction components and did not lead to a conditioned suppression of the food reinforced responding. Rate of responding during the pre-shock stimulus was observed to be relatively independent of changes in the maintaining schedules. Responding during the pre-shock stimulus could be conditioned and maintained after an extensive history of avoidance extinction. 相似文献
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Two recent experiments (Moray, 1959; Oswald, Taylor and Treisman, 1960) have shown that in dichotic listening, and in sleep one's own name seems to be responded to selectively. We have shown for 10 subjects, each listening binaurally to the same recording of a list of their names repeated at random 10 times, and masked by noise, that the subject's own name had a significantly lower threshold than other names. The effect we found was not significantly different from the one found by Oswald et al. during sleep and by Moray for the dichotic situation.
These three experiments taken together suggest that the same pattern-analysing mechanism is involved in normal listening, dichotic listening to the rejected message, and in discrimination during sleep. 相似文献
These three experiments taken together suggest that the same pattern-analysing mechanism is involved in normal listening, dichotic listening to the rejected message, and in discrimination during sleep. 相似文献
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Patricia M. Barbetta Ph.D. William L. Heward Ed.D. 《Journal of Behavioral Education》1993,3(3):217-233
An alternating treatments design was used to compare the effects of Active Student Response (ASR) error correction and No Response (NR) error correction during instruction of the capitals of states and countries. Three students with learning disabilities were provided one-to-one daily instruction on four sets of 14 unknown capitals (7 ASR capitals and 7 NR capitals). Student errors during instruction on ASR capitals were immediately followed by the teacher stating the capital and the student repeating it (an active student response). Errors on NR capitals were immediately followed by the teacher stating the capital while the student visually attended to a geography card with the correct capital handwritten on it (an on-task response). During instruction each of the three students correctly stated more capitals taught with ASR instruction than he or she stated with NR error correction. Results of same-day and next-day tests show that all three students learned more capitals with ASR error correction than with NR error correction The students also correctly stated more ASR error correction capitals on 1-week maintenance tests. 相似文献
50.
Three experiments establish the size-weight illusion as a primarily haptic phenomenon, despite its having been more traditionally considered an example of vision influencing haptic processing. Experiment 1 documents, across a broad range of stimulus weights and volumes, the existence of a purely haptic size-weight illusion, equal in strength to the traditional illusion. Experiment 2 demonstrates that haptic volume cues are both sufficient and necessary-for a full-strength illusion. In contrast, visual volume cues are merely sufficient, and produce a relatively weaker effect. Experiment 3 establishes that congenitally blind subjects experience an effect as powerful as that Of blindfolded sighted observers, thus demonstrating that visual imagery is also unnecessary for a robust size-weight illusion. The results are discussed in terms of their implications for both sensory and cognitive theories of the size-weight illusion. Applications of this work to a human factors design and to sensor-based systems for robotic manipulation are also briefly considered. 相似文献