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981.
Vera-Villarroel P Zych I Celis-Atenas K Córdova-Rubio N Buela-Casal G 《Psychological reports》2011,109(1):47-58
Posttraumatic stress disorder (PTSD) is an anxiety disorder in which an individual re-experiences a traumatic event, avoids situations related to it, and shows excessive arousal. The disorder appears after experiencing a life-threatening event, such as a war or a natural disaster. Thus, the validation of tests which assess the disorder after the earthquake on February 27, 2010, in Chile is crucial for its evaluation and subsequent intervention. The present study includes psychometric data for the Posttraumatic Stress Disorder Checklist-Civilian version (PCL-C) on a sample of 509 survivors of the disaster. Values indicate good psychometric properties of the questionnaire. 相似文献
982.
When people's health is threatened, they generally develop illness perceptions to make sense of their illness. The Illness Perception Questionnaire (IPQ-R), developed by Moss-Morris et al (2002), has been widely used in many countries to measure such representations. However, since studies in this crucial research area are lacking in Sweden a Swedish version of IPQ-R was validated with a focus on the seven subscales: timeline acute/chronic, timeline cyclical, consequences, personal control, treatment control, illness coherence and emotional representations. Using confirmatory factor analysis, the aim of the present study was to validate the internal structure of the Swedish version in a sample of 202 persons (144 men and 58 women) who had been diagnosed with myocardial infarction four months earlier. Additionally, inter-correlations among the seven subscales and external concurrent validity were also investigated. The results of confirmatory factor analysis revealed that, in line with the English version of the IPQ-R, the specified seven-factor model had a satisfactory fit. One item was however not considered reliable and was therefore excluded from the instrument. The internal consistency (Cronbach's alpha coefficients) and the inter-factor correlations were relatively similar to those reported in the validation study of the original English IPQ-R. In tests of concurrent validity, the seven IPQ-R subscales were, as hypothesized, mainly associated with external variables. To conclude, the Swedish version of the IPQ-R's seven dimensions, with one item removed, (total 37 items) was found to be a reliable and valid measure of illness perception. 相似文献
983.
Individuals display high levels of trust and express feelings of safety when interacting with social ingroup members. Here, we investigated whether cues related to ingroup membership would change perceptions of the safety of alcohol. Participants were exposed to images of beer in either a standard can or a can featuring the colors of their university (i.e., ‘fan cans’). We hypothesized that exposure to fan cans would change perceptions of the risks of beer drinking. Results showed that participants exposed to fan cans rated beer consumption as less dangerous (Experiment 1), were more likely to automatically activate safety-related mental content after unconscious perception of beer cues (Experiment 2), and viewed their ingroup's party practices as less dangerous (Experiment 3). These results provide evidence that ingroup-associated colors can serve as a safety cue for alcohol, which may in theory perpetuate alcohol-related risk-taking, already a cause for concern on college and university campuses. 相似文献
984.
Torres LV Araújo Sda C Sanchez CM Body S Bradshaw CM Szabadi E 《Journal of the experimental analysis of behavior》2011,95(1):57-74
Twelve rats made repeated choices on an adjusting-delay schedule between a smaller reinforcer (A) that was delivered immediately after a response and a larger reinforcer (B) that was delivered after a delay which increased or decreased by 20% depending on the subject's choices in successive blocks of trials. In two phases of the experiment (100 sessions and 40 sessions), reinforcer sizes were selected which enabled theoretical parameters expressing the rate of delay discounting and sensitivity to reinforcer size to be estimated from the ratio of the indifference delays obtained in the two phases. Indifference delays, calculated from adjusting delays in the last 10 sessions of each phase, were shorter when the sizes of A and B were 14 and 25 μl of a 0.6 M sucrose solution than when they were 25 and 100 μl of the same solution. The ratio of the indifference delays was significantly smaller than that predicted on the basis of an assumed linear relation between reinforcer size and instantaneous reinforcer value, consistent with a previous proposal that this relation may be hyperbolic in form. Estimates of the rate of delay discounting based on the ratio of the two indifference delays (mean, 0.08 s(-1)) were similar to values obtained previously using different intertemporal choice protocols. Estimates of the size-sensitivity parameter (mean 113 μl) were similar to estimates recently derived from performance on progressive-ratio schedules. In both phases of the experiment, adjusting delays in successive blocks of trials were analyzed using the Fourier transform. The power spectrum obtained from individual rats had a dominant frequency that corresponded to a period of oscillation of the adjusting delay between 30 and 100 trial blocks (mean, 78). Power in the dominant frequency band was highest in the early sessions of the first phase and declined with extended training. It is suggested that this experimental protocol may have utility in neurobehavioral studies of intertemporal choice. 相似文献
985.
Saccadic endpoint variability is often viewed as the outcome of neural noise occurring during sensorimotor processing. However, part of this variability might result from operant learning. We tested this hypothesis by reinforcing dispersions of saccadic amplitude distributions, while maintaining constant their medians. In a first experiment we reinforced the least frequent saccadic amplitudes to increase variability, and then reinforced the central part of the amplitude distributions to reduce variability. The target was placed at a constant distance from the fovea after the saccade to maintain the postsaccadic visual signal constant and an auditory reinforcement was delivered depending on saccadic amplitude. The second experiment tested the effects of the contingency. We reinforced high levels of variability in 4 participants, whereas 4 other participants were assigned to a yoked control group. On average, saccadic amplitude standard deviations were doubled while the medians remained mostly unchanged in the experimental participants in both experiments, and variability returned to baseline level when low variability was reinforced. In the control group no consistent changes in amplitude distributions were observed. These results, showing that variability can be reinforced, challenge the idea of a stochastic neural noise. We instead propose that selection processes constrain saccadic amplitude distributions. 相似文献
986.
The present study focused on the motivational predictors of coping with academic examination through the test of the contribution of self-determination for academic studies and achievement goals. Coping strategies, academic motivation and achievement goals were assessed among 199 undergraduate students. Regression analysis revealed that problem-focused coping is positively predicted by identified regulation and negatively by amotivation, whereas emotion-focused coping is positively predicted by introjected regulation and amotivation. Mastery approach goals contributed positively to problem-focused coping. Identified regulation and mastery approach goals made a unique positive contribution to problem-focused coping, and amotivation was negatively related. Students' coping actions may vary according to both the reasons why they engage in academic studies and the goals they pursue in this setting. 相似文献
987.
Two experiments examined the role of numerical distance in updating numerical information in working memory. In the first
experiment, participants had to memorize a new number only when it was smaller than a previously memorized number. In the
second experiment, updating was based on an external signal, which removed the need to perform any numerical comparison. In
both experiments, distance between the memorized number and the new one was manipulated. The results showed that smaller distances
between the new and the old information led to shorter updating times. This graded facilitation suggests that the process
by which information is substituted in the focus of attention involves maintaining the shared features between the new and
the old number activated and selecting other new features to be activated. Thus, the updating cost may be related to amount
of new features to be activated in the focus of attention. 相似文献
988.
Spoth R Guyll M Redmond C Greenberg M Feinberg M 《American journal of community psychology》2011,48(3-4):412-425
There is a knowledge gap concerning how well community-based teams fare in implementing evidence-based interventions (EBIs) over many years, a gap that is important to fill because sustained high quality EBI implementation is essential to public health impact. The current study addresses this gap by evaluating data from PROSPER, a community-university intervention partnership model, in the context of a randomized-control trial of 28 communities. Specifically, it examines community teams' sustainability of implementation quality on a range of measures, for both family-focused and school-based EBIs. Average adherence ratings approached 90% for family-focused and school-based EBIs, across as many as 6 implementation cohorts. Additional indicators of implementation quality similarly showed consistently positive results. Correlations of the implementation quality outcomes with a number of characteristics of community teams and intervention leaders were calculated to explore their potential relevance to sustained implementation quality. Though several relationships attained statistical significance at particular points in time, none were stable across cohorts. The role of PROSPER's continuous, proactive technical assistance in producing the positive results is discussed. 相似文献
989.
990.