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901.
Schumann S van der Linden N Klein O 《Cyberpsychology, behavior and social networking》2012,15(8):411-416
In line with Allport's contact hypothesis, previous research showed that direct intergroup contact can reduce prejudices. However, establishing face-to-face contact is not always feasible. We postulate that Facebook-groups are a setting where direct and observed intergroup contact can develop, reducing prejudices and increasing mutual acceptance. Analyzing the comments of nine Facebook-groups with the destructive and constructive conflict scale, our results indicated that the expression of prejudices decreased and that of mutual acceptance increased over time, both for in- and outgroup members of the Facebook-groups. Only the expression of less prejudices, but not that of more mutual acceptance was predicted by intergroup contact. The influence of group-based motivations on the engagement in intergroup contact is discussed, and the overall findings are integrated in Steele and Brown's process model of media practices. 相似文献
902.
Do color relations such as similarity or harmony influence the ease with which colored patterns can be perceived and held in mind? We tested the influence of a relation supported in research on color harmony--similarity of hue--on the capacity of visual short-term memory (VSTM) for colors in patterns. Palettes of 4 similar-hue colors were rated as more pleasant (harmonious) than dissimilar-color palettes. The palettes were used in a VSTM color task. Patterns of 9 to 15 colored squares were presented, and accuracy of color change detection was measured. Memory performance was higher overall for similar-color palettes than for dissimilar-color palettes (experiments 1 and 3). Is this due to color similarity per se, or due to the harmony between colors in similar palettes? A final experiment provided strong support for the importance of color similarity as opposed to harmony. Overall, the advantages for color similarity, in terms of number of color squares held in memory (memory capacity) were 26% to 45% over dissimilar colors. The results indicate that color relations can have a strong impact on the capacity for perceiving and retaining color patterns. 相似文献
903.
Young and older adults studied word pairs and later discriminated studied pairs from various types of foils including recombined word-pairs and foil pairs containing one or two previously unstudied words. We manipulated how many times a specific word pair was repeated (1 or 5) and how many different words were associated with a given word (1 or 5) to tease apart the effects of item familiarity from recollection of the association. Rather than making simple old/new judgments, subjects chose one of five responses: (a) Old-Old (original), (b) Old-Old (rearranged), (c) Old-New, (d) New-Old, (e) New-New. Veridical recollection was impaired in old age in all memory conditions. There was evidence for a higher rate of false recollection of rearranged pairs following exact repetition of study pairs in older but not younger adults. In contrast, older adults were not more susceptible to interference than young adults when one or both words of the pair had multiple competing associates. Older adults were just as able as young adults to use item familiarity to recognize which word of a foil was old. This pattern suggests that recollection problems in advanced age are because of a deficit in older adults' formation or retrieval of new associations in memory. A modeling simulation provided good fits to these data and offers a mechanistic explanation based on an age-related reduction of working memory. 相似文献
904.
Self-determination theory (Deci & Ryan, 2000, Intrinsic motivation and self-determination in human behaviour. New York: Plenum Publishing) highlights the impact autonomy supportive environments can have on exercise motivation and positive health outcomes. Yet little is known about whether differential effects occur as a function of which significant other is providing this support. Further, no research has examined the relationship between motivation and the social environment with participants' mental health and intentions to be physically active before entering an exercise intervention. Study participants were 347 British adults who were about to start an exercise referral scheme. Regression analyses revealed that the effects of autonomy support on mental health and physical activity intentions differed as a function of who provided the support (offspring, partner or physician), with the offspring having the weakest effects. A structural model was supported, indicating that autonomy support and more autonomous regulations led to more positive mental health outcomes and stronger intentions to be physically active. Knowledge of the social environmental and personal motivation of those about to commence an exercise programme can provide important insights for professionals supporting such efforts. 相似文献
905.
Lahaye M Fantini-Hauwel C Van Broeck N Bodart E Luminet O 《Psychology & health》2011,26(12):1678-1695
This study explored the mediating effect of coping strategies on the relationship between emotional competence (EC) and quality of life (QOL) among children with asthma. Participants were 87 children (M age?=?11.72, SD?=?2.58) with controlled and partially controlled asthma, undergoing everyday treatment. They filled in questionnaires assessing EC, coping strategies and QOL. Results showed that the association between some ECs and the QOL of children with asthma was fully mediated by two maladaptive cognitive coping strategies. Among children with asthma, a greater ability to differentiate their emotions, a reduced attention to bodily signals of emotions and a reduced analysis of their current emotional state were related to decreased engagement in two coping strategies ('Ignoring Asthma' and 'Worrying about Asthma'), which in turn increased their QOL. These findings show that EC has an indirect effect on QOL through very specific coping strategies. They also emphasise the importance of screening EC in children with asthma and the importance of developing and using multidisciplinary interventions for them. 相似文献
906.
In recent years, operant discrimination training procedures have been used to teach giant African pouched rats to detect tuberculosis (TB) in human sputum samples. This article summarizes how the rats are trained and used operationally, as well as their performance in studies published to date. Available data suggest that pouched rats, which can evaluate many samples quickly, are sufficiently accurate in detecting TB to merit further investigation as a diagnostic tool. 相似文献
907.
The relationship between ecstasy use and suicidal behavior among adolescents in the United States was examined. Data from the adolescent subsample (ages 12-17, N = 19,301) of the 2000 National Household Survey on Drug Abuse were used in the analyses. Information on adolescent substance use, suicidal behaviors, and related sociodemographic, family, and individual factors was obtained in the survey. The rate of past year suicide attempt among adolescents with lifetime ecstasy use was almost double that of adolescents who had used other drugs only, and nine times that of adolescents with no history of illicit drug use. In multinomial logistic regression analyses controlling for related factors, the effect of ecstasy use remained significant. Adolescent ecstasy users may require enhanced suicide prevention and intervention efforts. 相似文献
908.
Visual pop-out occurs when a unique visual target (e.g., a feature singleton) is present in a set of homogeneous distractors. However, the role of visual awareness in this process remains unclear. In the experiments reported here, we showed that even though subjects were not aware of a suppressed pop-out display, their subsequent performance on an orientation-discrimination task was significantly better at the pop-out location than at a control location. These results indicate that conscious visual awareness of a feature singleton is not necessary for it to attract attention. Furthermore, the subliminal pop-out effect disappeared when subjects diverted their attention toward a rapid sequential visual presentation task while presented with the same subliminal pop-out display. These results suggest that top-down attention is necessary for the subliminal pop-out effect and that the cognitive processes underlying attention and awareness are somewhat independent. 相似文献
909.
The kynurenine (KYN) pathway, which is initiated by indoleamine 2,3-dioxygenase, is the main tryptophan (TRP) metabolic pathway. It shares TRP with the serotonin (5-HT) pathway. We investigated the influence of inescapable-predator (rat) stress on behavior and brain TRP metabolism in mice. Male ICR mice (4W) were exposed to 20-min inescapable-predator stress. Behavior on an elevated plus-maze, and TRP, KYN, and 5-HT levels in the prefrontal cortex, hippocampus, amygdala, and dorsal raphe nuclei were measured 1 and 4 weeks after stress exposure. Predator stress increased the number of open-arm entries (NOA) 4 weeks after stress exposure without altering the number of closed-arm entries (NCA). Thus, the open/closed-arm entry ratio (NOA/NCA) increased after stress exposure. Predator stress increased KYN levels in the prefrontal cortex (until 4 weeks after stress exposure) and dorsal raphe nuclei (for 1 week after stress exposure), decreased 5-HT levels in all brain regions (until 4 weeks after stress exposure). Thus, predator stress increased the KYN/5-HT ratio in all regions, in particular in the prefrontal cortex and hippocampus until 4 weeks after stress exposure. Predator stress shifted the balance between the KYN and 5-HT pathways to the KYN pathway, and induced behavioral disinhibition. 相似文献
910.
Quist N 《The Journal of clinical ethics》2011,22(2):191-193
Social media challenge--or have already redefined--conventional boundaries of public and private, personal and professional, friendship, and social relations generally. Here, I consider how these developments may affect professionalism, the physician-patient relationship, and our cultural experiences in a wholly different and unexpected way. 相似文献