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531.
Facial expressions are critical for effective social communication, and as such may be processed by the visual system even when it might be advantageous to ignore them. Previous research has shown that categorising emotional words was impaired when faces of a conflicting valence were simultaneously presented. In the present study, we examined whether emotional word categorisation would also be impaired when faces of the same (negative) valence but different emotional category (either angry, sad or fearful) were simultaneously presented. Behavioural results provided evidence for involuntary processing of basic emotional facial expression category, with slower word categorisation when the face and word categories were incongruent (e.g., angry word and sad face) than congruent (e.g., angry word and angry face). Event-related potentials (ERPs) time-locked to the presentation of the word-face pairs also revealed that emotional category congruency effects were evident from approximately 170 ms after stimulus onset.  相似文献   
532.
Depressive symptoms and cognitive decline are associated in older age, but research is inconsistent about whether one condition influences the development of the other. We examined the directionality of relations between depressive symptoms and perceptual speed using bivariate dual change score models. Assessments of depressive symptoms and perceptual speed were completed by 1,206 nondemented older adults at baseline, and after 2, 8, 11, and 15 years. After controlling for age, education, baseline general cognitive ability, and self-reported health, allowing depressive symptoms to predict subsequent change in perceptual speed provided the best fit. More depressive symptoms predicted subsequently stronger declines in perceptual speed over time lags of 1 year.  相似文献   
533.
The stress associated with providing care for a spouse diagnosed with Alzheimer's disease can have adverse effects on cardiovascular health. One potential explanation is that chronic caregiving stress may contribute to the development of atherosclerosis. The purpose of this study was to determine whether the duration that one has provided care is associated with the degree of atherosclerotic burden, as measured by carotid artery intima-media thickness (IMT). One hundred and ten Alzheimer caregivers [mean age 74?±?8 (SD) years, 69% female] underwent in-home assessment of carotid artery IMT via B-mode ultrasonography. Data regarding medical history, blood pressure, and multiple indicators of caregiving stress were also collected. Multiple regression indicated that duration of care was positively associated with IMT measured in the internal/bifurcation segments of the carotid artery (β?=?0.202, p?=?0.044) independent of risk factors such as age, gender, body mass index, smoking history, sleep quality, hypertension status, and caregiving stressors. Duration of care was positively associated with IMT in the common carotid artery, but the relationship was not significant. These findings provide more evidence of the link between chronic caregiving stress and cardiovascular disease and indicate that enduring the experience of caregiving over a period of years might be associated with atherosclerotic burden.  相似文献   
534.
This study examined the occurrence of problem situations in the peer and school domains and their relation to adjustment among urban adolescents. Students from three urban middle schools (N = 176) serving a predominantly African American population rated 61 problem situations identified in a previous qualitative study and completed measures of adjustment. Ratings of frequency and difficulty confirmed the relevance of these situations for this population. Confirmatory factor analyses suggested that covariation in the frequency and difficulty of problem situations could be represented by separate factors representing peer situations involving friends, other peer situations, and school situations. The number of different problem situations experienced was significantly correlated with physical and relational aggression, delinquency, depression, anxiety, and self-worth. Several of these relations were strongest for peer situations that did not involve friends. There were few gender differences in the strength of these relations.  相似文献   
535.
The present study was designed to assess sex-dimorphic color preferences in children with gender identity disorder (47 boys, 18 girls), clinical controls (65 boys, 35 girls), and community controls (65 boys, 35 girls). The mean age of the children was 7.63 years (range?=?3–12 years). Children were shown a hexagon-shaped display of 144 colors extracted from PowerPoint?. Each child was asked to choose his or her three favorite colors (Trials 1–3) by pointing to them, naming them, and then to provide a justification for each choice. From the entire array, children labeled a total of 11 different colors: black, blue, brown, gray, green, orange, pink, purple, red, white, and yellow. For three of the colors (blue, pink/purple, and red), there was evidence for normative sex differences in color preference, and, for the colors blue and pink/purple, the gender-referred children showed inverted patterns of color preference. For the color blue, luminance values showed that the gender-referred boys and control girls preferred lighter shades, whereas the gender-referred girls and control boys preferred darker shades. Qualitative analysis indicated that gender-specific justifications were uncommon, even for the sex-dimorphic colors. Gender-referred children showed inverted gender-stereotyped color preferences, which are likely related to their more general pattern of cross-gender identification. Principles of gender-differentiated development derived from gender-schema theory are used to explain the group differences in color preferences.  相似文献   
536.
537.
The Community Alcohol Use Scale (CAUS) was developed as a continuous, reliable, valid, and acceptable measure for primary prevention studies. Items were written following a comprehensive review of the literature on alcohol dependence and alcoholism. Based upon the responses of 315 respondents to the 100-item initial version of the scale, the 45-item CAUS was developed. The CAUS was then cross-validated on a local sample (n = 274) and a provincial sample (n = 745). Estimates of internal consistency were .91, .96, and .94, respectively, for the initial and cross-validation samples. Correlations of .48 and .69 were obtained between the CAUS and the Michigan Alcohol Screening Test for the initial and local cross-validation samples. In the provincial cross-validation sample a correlation of .62 was obtained between the CAUS and the Usual Weekly Alcohol Index. Preliminary cutting scores were developed to identify those at risk for alcoholism, and alcoholics. The CAUS has potential use as an evaluative and predictive instrument in a variety of primary prevention programs.  相似文献   
538.
Rats obtained all of their water by licking a metal tube during a series of daily 1-hour sessions. When the tube was freely available throughout, each rat showed the classic temporal pattern of unconstrained drinking: As the session progressed, drinking bouts generally grew shorter and pauses grew longer. In subsequent sessions the tube was opened and closed independently of the rat's behavior, on a schedule that gave the rat a chance to duplicate the exact inverse of its unconstrained baseline pattern. Thus, as the inversion session progressed, the opportunities to drink generally grew longer and the enforced pauses grew shorter. When the rats were forced away from their unconstrained patterns of drinking and pausing, their total time spent drinking consistently fell short of previous values, but total licks and volumetric intake remained at previous levels. The same results occurred under an identity schedule, a series of openings and closings that duplicated the unconstrained pattern of drinking and pausing. The results have implications for theories that assume that instrumental performance under schedule constraint derives from the animal's defense of a measured set-point.  相似文献   
539.
540.
Pigeons' pecks were maintained on concurrent variable-interval 1-min variable-interval 3-min schedules of reinforcement, with a changeover delay of 2 sec. When changeover delay was increased successively to 5.0, 7.5, and 12.5 sec (Exp. I) the actual relative rate of reinforcement for the variable-interval 3-min key decreased progressively for two birds, abruptly for two other birds, and the subjects devoted proportionately less of their time and responding to that key. However, the relative performance measures (relative time and relative responding) approximated the actual relative rate of reinforcement, with a maximum discrepancy of 11%, over all changeover delay values investigated. Experiment II attempted to lengthen response-run durations on the variable-interval 3-min key so that they were long enough to meet the changeover delay requirement at each new changeover delay value, by progressively increasing the changeover delay by 0.5-sec increments. With this procedure the actual relative rate of reinforcement approximated more closely the scheduled relative rate as changeover delay increased. As in Exp. I, relative performance measures approximated the actual relative reinforcement rate (maximum discrepancy 17%).  相似文献   
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