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171.
Tested a preventive intervention in which peer telephone dyads were developed for low-income, community-living, elderly women with low perceived social support. After an initial assessment, respondents were randomly assigned to either an assessment-only control or received 10 weeks of friendly staff telephone contact. After a second assessment, participants receiving the staff contact were randomly assigned to continue that contact or were paired in dyads to continue phone contact with one another. Dependent variables were measures of perceived social support, morale, depression, and loneliness. All groups, particularly the staff contact group, showed some improvement in mental health scores over time, but there were no significant differences between intervention groups, or between intervention and assessment-only control groups. The results suggest that participation in the study and in personal assessment interviews at home were probably morale enhancing, and that additional telephone contact did not significantly add to that effect. Evidence also indicates that, in this sample, low perceived family support was significantly related to poor mental health, so it is possible that a program designed to increase friend support may have been the wrong intervention.  相似文献   
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In the UK, excessive fruit machine playing is the most documented form of pathological gambling amongst adolescents. Although there have been a few retrospective questionnaire studies in adolescent fruit machine gambling, there has been very little systematic observational fieldwork into the behaviour. The studies reported explore the social world of fruit machine playing using data collected via the monitoring of 33 UK amusement arcades employing participant and non-participant observation methodologies. The basic aims were to observe the arcade clientele and their behavioural characteristics, and to examine motivations for machine playing. Results suggest that level of adolescent gambling depends upon both time of day and time of year, and regular players conform to rules of etiquette and display stereotypical behaviours when playing fruit machines. The results also suggest that adolescents play fruit machines for a wide range of reasons including fun, to win money, to socialize, to escape and for excitement, and that inland and coastal arcades are frequented by different clienteles, probably as a function of the amusement machine available.  相似文献   
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A differential conditioning study examined whether an acoustic startle probe, presented during extinction of an aversively conditioned visual stimulus, potentiated the reflex eyeblink response in humans and whether this potentiation varied with the change in affective valence of the conditioned stimulus. Sixty college students were randomly assigned to view a series of two slides, depicting either unpleasant/highly arousing, unpleasant/moderate arousing, neutral/calm, pleasant/moderate arousing or pleasant/highly arousing scenes and objects (duration: 8 sec). During preconditioning (8 trials) and extinction (24 trials) acoustic startle probes (white noise bursts [50 ms; 95 dBA] were administered during and between slide presentation). During acquisition (16 trials) CS+ was reinforced by an electric shock. Startle response magnitudes significantly increased from preconditioning to extinction and were substantially larger to CS+. Conditioned startle reflex augmentation linearly increased with the pleasantness of the slides. Furthermore, subjects showed a greater post-conditioning increase of judged aversiveness to slides that they had previously reported to be more pleasant, exactly paralleling the startle reflex results.

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Experimentally induced failure sometimes produces helplessness and sometimes facilitation on subsequent tasks. A model which accounts for this in terms of variations in perceived task difficulty and importance and variations in the cost of effort is proposed. Predictions from the model were confirmed in two experiments using the finger shuttlebox. When subjects expected the test task to be easy, importance of test outcome did not affect performance. However, when they expected the test task to be difficult, low outcome importance led to debilitation, and high importance to facilitation. If, in this condition, subjects experienced initial failure on the task perceived as difficult and important, helplessness rather than facilitation was observed. The model proposed may account for some of the conflicting results obtained in laboratory studies of human helplessness.  相似文献   
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A within-subject comparison was made of the effects of methylphenidate (Ritalin) and response cost in reducing the off-task behavior of two boys, 7 and 8 years of age, who had been diagnosed as having an attentional deficit disorder with hyperactivity. Several dosages of Ritalin (5 to 20 mg/day) were evaluated with the results indicating varying effects of the drug for both children. Response cost (with free-time as the reinforcer) was superior to Ritalin in raising levels of on-task behavior and in improving academic performance.  相似文献   
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