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181.
Three experiments are reported that examine whether fast finger-tapping sequences are entirely planned before execution starts (advance planning), or if they can be started while planning is still under way (distributed planning). Subjects performed finger tapping sequences of three to eight taps at a high rate, under both simple and 2-choice reaction time (RT) conditions. The sequences differed in the location of an accentuated element within them. The RT to choose between sequences with different accent locations progressively decreased as an inverse function of the time-distance between the initial tap and the first point at which the alternative sequences differed. The shortening in choice reaction time (CRT) was never accompanied by noticeable changes in the inter-response times or force patterns of the tapping sequences. The RT to initiate sequences with accent location known beforehand (SRT condition) showed, in two of three experiments, a weak decreasing trend as the accentuated tap shifted away from the beginning of the sequence. The SRT results suggest a possible predominance of advance planning when the same sequence is repeated over a series of trials. The CRT results are taken as evidence that planning of the sequence beyond the unpredictable tap could be distributed before and after sequence initiation. Several factors are discussed that may influence the balance between planning in advance of, and planning in parallel with, sequence execution.  相似文献   
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This research tested the hypothesis that children's perceptions of academic competence and their personal control over school-related performance affects subsequent intrinsic interest and preference for challenge in an evaluative setting. In a correlational study, children's self-reported perceptions of academic competence and personal control were found to relate positively to their intrinsic interest in schoolwork and preference for challenging school activities. A subset of this sample was exposed to varying levels of a controlling directive, and preference for challenge was assessed behaviorally during a free-choice period in which subjects were unaware that they were being observed. As predicted, the data indicated that when given the evaluative, controlling directive, children who had high perceptions of academic competence and control preferred a greater challenge than did children whose perceptions were low on these measures. No difference between groups in terms of preference for challenge was evident when no controlling directive was presented. These findings are discussed in terms of theories of intrinsic motivation and potential processes that underly these effects.  相似文献   
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The evolution of human intrasexual competition: tactics of mate attraction   总被引:4,自引:0,他引:4  
Darwin's theory of sexual selection suggests that individuals compete with members of their own sex for reproductively relevant resources held by members of the opposite sex. Four empirical studies were conducted to identify tactics of intrasexual mate competition and to test four evolution-based hypotheses. A preliminary study yielded a taxonomy of tactics. Study 1 used close-friend observers to report performance frequencies of 23 tactics to test the hypotheses. Study 2 replicated Study 1's results by using a different data source and subject population. Study 3 provided an independent test of the hypotheses in assessing the perceived effectiveness of each tactic for male and female actors. Although the basic hypotheses were supported across all three studies, there were several predictive failures and unanticipated findings. Discussion centers on the heuristic as well as predictive role of evolutionary theory, and on implications for other arenas of intrasexual competition.  相似文献   
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Depression and mental control: the resurgence of unwanted negative thoughts   总被引:6,自引:0,他引:6  
In three experiments we examined depressed individuals' mental control abilities and strategies. Experiment 1 revealed that although depressed college students were initially successful in suppressing negative material, they eventually experienced a resurgence of unwanted negative thoughts. Analysis of subjects' stream-of-consciousness reports indicated that this resurgence was associated with the use of negative thoughts as distracters from the unwanted item. In Experiment 2 depressed subjects acknowledged that positive distracters were more effective than negative ones in suppressing negative thoughts. This acknowledgement suggests that depressed subjects in Experiment 1 did not deliberately focus on negative distracters but that those thoughts automatically occurred because they were highly accessible. Experiment 3 demonstrated that depressed subjects' use of positive distracters could be increased somewhat when we provided such distracters and made them easily accessible. Taken together, the findings suggest that depression involves an enhanced accessibility of interconnected negative thoughts that can undermine mental control efforts.  相似文献   
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Subjects (N= 28) performing a complex disjunctive concept-formation task on a microcomputer were given the opportunity to seek help following failure to correctly identify concepts. The proportion of those seeking help was significantly greater when the source of help was the computer itself (86%) rather than another person (36%). Consistent with past research, those who did not ask for help gave reasons other than the potential negative social consequences of doing so. Self-report data and a systematic test for the presence of experimenter-induced demand ruled out several possible sources of confounding. The results have implications for designers of time-sharing and networked computer systems.  相似文献   
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Social status variables have been shown to influence attributional judgments, but their effects have been demonstrated almost entirely in experimental settings. The influence of such statuses in experimental settings may differ from their influence in natural settings. We examined the influence on attributional judgments of the status characteristics of both subjects and actors in conjunction with variations in the degree of “real world” characteristics of both subjects and social context. These comparisons were drawn through a partial replication of earlier research investigating the effects of a social status variable, victim sex, and a situational variable—type of assault—on attributions about an assault victim. The social status characteristic, victim sex, had less influence on attributions in an adult juror sample than in a student sample and testimony-related characteristics were more influential in the adult juror sample than in the student sample. Thus, the categories of variables that influence attributions appear to depend on the context of judgment and on the breadth of subjects' life experience. These findings are discussed and we conclude with the caution that careful identification of the differences produced by context and subject characteristics is necessary to support generalization of laboratory-based research.  相似文献   
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