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981.
982.
Research has demonstrated that sharing with others is rewarding, suggesting a proximal mechanism of humans’ extraordinary tendency to engage in prosocial behavior. The current study explored the cognitive basis of the relation between generosity and happiness early in ontogeny. We demonstrate that preschool children understand the relation between generosity and happiness. Moreover, our results show that children's emotion ratings are predictive for their subsequent sharing behavior. This finding provides evidence for the theoretical claim that prosocial behavior may be related to the anticipation of positive feelings, and that this mechanism may explain early instances of generosity in preschool children.  相似文献   
983.
Leadership behaviour has been identified as an important antecedent of workplace bullying since managers may prevent, permit, or engage in the mistreatment of others. However, the issue of how managers respond when bullying occurs has received limited attention. With this in mind, the aim of this study was to explore how managers behave when bullying occurs in their work group and to elucidate the contextual issues that underlie this behaviour. This was achieved through analysis of in-depth interviews with individuals involved in cases of bullying. The findings revealed a typology of four types of management behaviour in cases of bullying, each underpinned by contextual factors at the individual, group, and organizational levels. The study shows that the role of leadership in workplace bullying is more complex than previously thought and suggests several ways in which managers and organizations could deal with bullying behaviour.  相似文献   
984.
The objective of this study was to examine the effectiveness of a 12 week weight loss intervention within a commercial fitness centre on body weight, moderate to vigorous physical activity (MVPA), dietary intake, and behavioural regulations for exercise and healthy eating. Using a quasi-experimental design, the intervention group received weekly coaching sessions and bi-weekly seminars designed to increase MVPA and improve dietary intake. Outcome variables were assessed at three time points over a six month period. Results showed a significant interaction for body weight (p = .04) and dietary changes (p < .05) following the weight loss challenge but were not maintained across the six month period. Changes in behavioural regulations favoured the intervention condition. Results imply that a 12 week weight loss challenge within a commercial fitness centre may be effective at prompting short-term weight loss and support the internalization of behavioural regulations specific to healthy eating and exercise.  相似文献   
985.
986.
987.
Among adolescents, religiosity has been associated with lower rates of marijuana use, though few studies have examined its impact on the perceived risk of use. There is strong support that perceived risk of using marijuana is negatively correlated with the frequency of use. We examined the relationship among religiosity, perceived risk, and marijuana use from a national survey of adolescents that contained questions about lifetime, weekly, and past month substance use, social support, religious involvement and attitudes, and perceived riskiness of use. We tested a structural equation model of relationships among latent variables of religiosity and perceived risk, and an observed variable of total days of marijuana use in the past 12 months. Results indicated the model was a good fit to the data and described a mediating relationship of perceived risk of use between religiosity and marijuana use. Implications for leveraging religiosity in prevention of substance use are discussed.  相似文献   
988.
Huntington’s disease (HD) patients show reduced flexibility in inhibiting an already-started response. This can be quantified by the stop-signal task. The aim of this study was to develop and validate a sheep version of the stop-signal task that would be suitable for monitoring the progression of cognitive decline in a transgenic sheep model of HD. Using a semi-automated operant system, sheep were trained to perform in a two-choice discrimination task. In 22% of the trials, a stop-signal was presented. Upon the stop-signal presentation, the sheep had to inhibit their already-started response. The stopping behaviour was captured using an accelerometer mounted on the back of the sheep. This set-up provided a direct read-out of the individual stop-signal reaction time (SSRT). We also estimated the SSRT using the conventional approach of subtracting the stop-signal delay (i.e., time after which the stop-signal is presented) from the ranked reaction time during a trial without a stop-signal. We found that all sheep could inhibit an already-started response in 91% of the stop-trials. The directly measured SSRT (0.974 ± 0.04 s) was not significantly different from the estimated SSRT (0.938 ± 0.04 s). The sheep version of the stop-signal task adds to the repertoire of tests suitable for investigating both cognitive dysfunction and efficacy of therapeutic agents in sheep models of neurodegenerative disease such as HD, as well as neurological conditions such as attention deficit hyperactivity disorder.  相似文献   
989.
Social anxiety disorder (SAD) models posit vigilance for external social threat cues and exacerbated self-focused attention as key in disorder development and maintenance. Evidence indicates a modified dot-probe protocol may reduce symptoms of SAD; however, the efficacy when compared to a standard protocol and long-term maintenance of treatment gains remains unclear. Furthermore, the efficacy of such protocols on SAD-related constructs remains relatively unknown. The current investigation clarified these associations using a randomized control trial replicating and extending previous research. Participants with SAD (n = 113; 71% women) were randomized to complete a standard (i.e. control) or modified (i.e. active) dot-probe protocol consisting of 15-min sessions twice weekly for four weeks. Self-reported symptoms were measured at baseline, post-treatment, and 4-month and 8-month follow-ups. Hierarchical linear modeling indicated significant self-reported reductions in symptoms of social anxiety, fear of negative evaluation, trait anxiety, and depression, but no such reductions in fear of positive evaluation. Symptom changes did not differ based on condition and were maintained at 8-month follow-up. Attentional biases during the dot-probe task were not related to symptom change. Overall, our results replicate support for the efficacy of both protocols in reducing symptoms of SAD and specific related constructs, and suggest a role of exposure, expectancy, or practice effects, rather than attention modification, in effecting such reductions. The current results also support distinct relationships between fears of negative and positive evaluation and social anxiety. Further research focused on identifying the mechanisms of change in attention modification protocols appears warranted.  相似文献   
990.
Investigations of neurodegenerative disorders may reveal functional relationships in the cognitive system. C.S. was a 63‐year‐old right‐handed man with post‐mortem confirmed Pick's disease with a range of progressive impairments including non‐fluent aphasia, speech, limb, oculomotor, and buccofacial apraxia, but mostly intact intelligence, perception, orientation, memory, semantics, and phonology. During progression, agrammatism in writing with impairments in syntactic comprehension emerged in parallel with an unusual graphomotor deficit in drawing and writing, with an increasing deterioration of graphic short‐term memory. We investigated C.S.'s graphomotor deficit longitudinally using tests of writing and drawing on letters, words, and sentences and drawing to command and copying. We also tested C.S.'s short‐term graphemic buffer experimentally. Analysis showed deficits on selective aspects of graphomotor implementation of writing and drawing, mainly affecting the production of circles and curves, but not short straight lines in drawing and writing, and graphomotor short‐term memory, which paralleled impairments of written syntax and syntactic comprehension. We believe this to be the first detailed analysis of such an unusual progressive impairment in graphomotor production, which may be related to problems with agrammatic agraphia and impairments affecting shared components of cognition reflecting damage to shared neural networks. Alternatively, they may simply reflect the effects of coincidental damage to separate mechanisms responsible for aspects of writing, drawing, and syntactic processing. Longitudinal investigations of emerging deficits in progressive conditions like C.S.'s provides an opportunity to examine the progressive emergence of symptoms in an individual with multiple progressive impairments as they appear and examine putative relationships between them.  相似文献   
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