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Recent theory and research suggest that perfectionism is a personal factor contributing to athletes’ vulnerability to doping (using banned substances/drugs to enhance sporting performance). So far, however, no study has examined what aspects of perfectionism suggest a vulnerability in junior athletes. Employing a cross-sectional design, this study examined perfectionism and attitudes towards doping in 129 male junior athletes (mean age 17.3 years) differentiating four aspects of perfectionism: perfectionistic strivings, perfectionistic concerns, parental pressure to be perfect, and coach pressure to be perfect. In the bivariate correlations, only parental pressure showed a positive relationship with positive doping attitudes. In a multiple regression analysis controlling for the overlap between the four aspects, perfectionistic strivings additionally showed a negative relationship. Moreover, a structural equation model examining the relationships between all variables suggested that coach pressure had a negative indirect effect on attitudes towards doping via perfectionistic strivings. The findings indicate that perceived parental pressure to be perfect may be a factor contributing to junior athletes’ vulnerability to doping, whereas perfectionistic strivings may be a protective factor. 相似文献
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Louis D. Matzel 《Learning & behavior》1985,13(2):187-193
A series of experiments used food-deprived pigeons to examine several parameters of reinforcement omission in an attempt to control changes of keypeck response measures on a subsequent schedule. In Experiments 1 and 2, the pigeons were tested with a multiple fixed-ratio schedule on which reinforcement was occasionally omitted at the completion of the first component. The duration of the delay occurring in lieu of reinforcement was systematically varied. In Experiment 3, the stimulus that signaled the second component of the schedule was altered to appear either more or less similar to the stimulus that signaled the first component. Two principal results are reported: (1) Response latency decreased and, to a much lesser extent, terminal response rate increased as the delay occurring in lieu of reinforcement decreased; and (2) both latency decrease and response-rate increase were enhanced by a second component stimulus which was similar to the first. The results are evaluated in terms of Amsel’s frustration theory and an analysis by Staddon which suggests that reinforcement inhibits responding. The data appear to support Staddon’s argument that rate increases and latency decreases following reinforcement omission are largely a function of an attenuation of the inhibitory influence of reinforcement, an effect that is enhanced by stimulus generalization. Accordingly, it is proposed that an animal’s response to reinforcement omission is determined by a stimulus complex that minimally includes the omission event and component cues. 相似文献
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Louis M. Herman David S. Matus Elia Y. K. Herman Marina Ivancic Adam A. Pack 《Learning & behavior》2001,29(3):250-264
We assigned gestural symbols to nine body parts of a bottlenosed dolphin (Tursiops truncatus). The dolphin was first trained to touch any floating object it chose with the body part indicated by a gestural symbol. In Experiment 1, we tested the dolphin’s ability to now touchspecific gesturally referenced objects using specific gesturally referenced body parts. In Experiment 2, we tested its ability to either touch or toss gesturally referenced objects with gesturally referenced body parts or to simply display those body parts or shake them back and forth. The acts of touching, tossing, displaying, and shaking were each associated with specific gestures and appeared in random sequences within test sessions. The results demonstrated highly significant levels of performance throughout these tasks, including many successes on the first occasions of new body-part uses. These findings provided strong evidence that the gestural symbols we used for body parts were semantically processed and understood by the dolphin as representing those body parts. 相似文献
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