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981.
Based on the hierarchical model of intrinsic and extrinsic motivation (Vallerand, 1997), the purpose of the present research was to propose and test a model that posits that individuals’ perceptions of autonomy support from their supervisor in an activity (e.g., coach, teacher) and their global autonomous motivation jointly promote their autonomous (contextual) motivation toward the activity. In turn, contextual autonomous motivation positively predicts interest in the activity, whereas it negatively predicts intentions to drop out of the activity. In Study 1, the model was tested with a sample of 206 competitive athletes registered in the French Skiing Federation. In Study 2, a short longitudinal design was used, and the sample was composed of 206 French high school students (128 female, 78 male). Results from structural equation modeling analyses supported the hypothesized model. These results provided support for the hierarchical model of intrinsic and extrinsic motivation (Vallerand, 1997). The implications of the findings and future research avenues are discussed in light of the hierarchical model and self-determination theory. 相似文献
982.
Jake J. Klassen Douglas A. Williams Bruce Bolster Robert W. Tait 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》2002,55(1):27-42
Three experiments investigated the conditions under which electrolytic lesions of the dorsolateral periaqueductal grey (dlPAG) facilitate conditioned defensive freezing in the rat ( Rattus norvegicus ). Experiment 1 found that dlPAG lesions placed before context-shock pairings facilitated conditioned defensive freezing with massed but not distributed shock. No such effect was found in Experiment 2, when the lesions were placed after context-shock pairings. Experiment 3 found that dlPAG lesions facilitated subsequent conditioning with massed but not a single shock. In addition, no differences in sensitivity to thermal or shock pain were evident in lesioned and unlesioned rats. Taken together, these results are consistent with the suggestion that dlPAG activation interferes with the processing of contextual cues during association formation. 相似文献
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984.
This paper reports the results of a controlled field experiment in which voice communication was introduced into an existing online community (online gaming guilds within the popular game “World of Warcraft”), comparing a mix of voice and text with text only. Quantitative results suggest increases in liking and trust due to the addition of voice, as well as insulation from unexpected negative impacts of text‐only play. The findings are discussed with respect to social capital, cyberbalkanization, and the general computer‐mediated communication literature, with special attention paid to social information processing theory. 相似文献
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Cheng RK MacDonald CJ Williams CL Meck WH 《Learning & memory (Cold Spring Harbor, N.Y.)》2008,15(3):153-162
Choline availability in the maternal diet has a lasting effect on brain and behavior of the offspring. To further delineate the impact of early nutritional status, we examined effects of prenatal-choline supplementation on timing, emotion, and memory performance of adult male and female rats. Rats that were given sufficient choline (CON: 1.1 g/kg) or supplemental choline (SUP: 5.0 g/kg) during embryonic days (ED) 12-17 were trained with a differential reinforcement of low-rate (DRL) schedule that was gradually transitioned through 5-, 10-, 18-, 36-, and 72-sec criterion times. We observed that SUP-females emitted more reinforced responses than CON-females, which were more efficient than both groups of males. In addition, SUP-males and SUP-females exhibited a reduction in burst responding (response latencies <2 sec) compared with both groups of CON rats. Furthermore, despite a reduced level of burst responding, the SUP-males made more nonreinforced responses prior to the DRL criterion as a result of maintaining the previous DRL criterion following transition to a new criterion. In summary, long-lasting effects of prenatal-choline supplementation were exhibited by reduced frustrative DRL responding in conjunction with the persistence of temporal memory in SUP-males and enhanced temporal exploration and response efficiency in SUP-females. 相似文献
990.
The properties of long-term potentiation (LTP) mirror those of associative memory in a number of interesting ways. Although plasticity at monosynaptic connections is not expected to account for the varied subtle characteristics of distributed memories, nonetheless it is important to establish how far the parallels can be drawn. Here, we briefly address whether properties of LTP such as its duration, reversibility, savings and reconsolidation relate to corresponding memory phenomena. We then address whether LTP stabilization in fact requires protein synthesis, as this has been challenged in recent times much like the necessity for protein synthesis in the consolidation of long-term memory has been queried. We conclude that the case is still very strong for a necessary role of protein synthesis in LTP stabilization, even though the identities of the synthesized proteins and their contributions to the LTP process are not fully understood. However, we highlight areas of research that could be usefully conducted to further our understanding of the properties and protein synthesis-dependence of LTP. 相似文献