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791.
Two experiments are reported, which examined the relative contributions of preload (resting force level), change of force, and the time taken to achieve the force in determining isometric force variability. The findings showed that change of force is the strongest determiner of peak force variability but that preload and time to peak force have smaller though systematic effects. A formula that predicts peak force variability is proposed, with preload as an additive effect to the ratio between the change of force level and the square root of time to peak force. These findings confirm that these three impulse variables are significant in predicting force variability and that the impact of rate of force on peak force variability is nonlinear. 相似文献
792.
The present study examined relationships between young children's memory knowledge and their use of taxonomic and color memory organization. Forty-eight 5-, 6-, and 7-year-olds were administered metamemory tests of organization-strategy knowledge and general memory knowledge, and were tested on two study-recall tasks before, and two study-recall tasks after, training in the use of color or taxonomic organization. Study organization (grouping) scores were low before training, but improved significantly in post-training tasks. Training effects were less pronounced for retrieval organization (clustering) and did not occur for item recall. Relationships between taxonomic study and retrieval organization were apparent only for the 7-year-olds, while relationships between color organization at study and retrieval were not apparent at any age level. Relationships between metamemory, strategy-use, and recall proficiency were evident on some tasks for 7-year-olds, but not for younger children. Although teacher ratings of the children's mastery orientations were also found to be related to recall proficiency for the older subjects, specific strategy knowledge was a more consistent correlate of strategy use and amount recalled. 相似文献
793.
G Chastain 《The Journal of general psychology》1990,117(3):295-301
The present study was conducted to determine whether sensitivity to a member of a pair of stimulus letters projecting to the parafovae would be improved by presenting that member at fixation. The effect was examined for the pair member appearing at a constant distance from fixation, which always was flanked to its inner or outer side. Contrary to expectations based upon results reported by Geiger and Lettvin (1986), observed accuracy changes were found to be due to response bias rather than to sensitivity enhancement. 相似文献
794.
When cognitive exertion does not yield cognitive gain: toward an informational explanation of learned helplessness 总被引:4,自引:0,他引:4
This study tested a new information-processing explanation of learned helplessness that proposes that an uncontrollable situation produces helplessness symptoms because it is a source of inconsistent, self-contradictory task information during problem-solving attempts. The flow of such information makes hypothesis-testing activity futile. Prolonged and inefficient activity of this kind leads in turn to the emergence of a state of cognitive exhaustion, with accompanying performance deficits. In 3 experiments, Ss underwent informational helplessness training (IHT): They were sequentially exposed to inconsistent task information during discrimination problems. As predicted, IHT was associated with subjective symptoms of irreducible uncertainty and resulted in (a) performance deterioration on subsequent avoidance learning, (b) heightened negative mood, and (c) subjective symptoms of cognitive exhaustion. 相似文献
795.
Depressive self-presentation: beyond self-handicapping 总被引:1,自引:0,他引:1
An experiment was conducted to examine the notion that depressives' responses would reflect a protective self-presentation style (Hill, Weary, & Williams, 1986), the underlying goal of which would be the avoidance of future performance demands and potential losses in self-esteem. In this study, depressed and nondepressed Ss were asked to perform a relatively simple visual-motor task. Half of the depressed and half of the nondepressed Ss were told that if they were successful at the task, they would be asked to perform a 2nd, similar task. The remaining Ss were given no such expectation of future performance. We predicted and found that depressed compared with nondepressed Ss strategically failed at the task when presented with the possibility of future performance and further losses in esteem. Moreover, this strategic failure was associated with some costs; depressed-future performance expectancy Ss experienced more discomfort or negative affect as a result of their performance. The relationship between this depressive self-presentation and self-handicapping strategies is discussed. 相似文献
796.
Although research has demonstrated that social interactions influence psychological well-being, little is known about what specific actions victims of stressful life events experience as helpful or unhelpful. Wortman and Dunkel-Schetter (1979) previously suggested that victims frequently experience rejection, withdrawal, and communication problems with those close to them. To address these issues, 55 cancer patients were interviewed concerning the specific actions they found to be helpful or unhelpful from several potential support providers: spouse, other family members, friends, acquaintances, others with cancer, physicians, and nurses. The data indicated that the Wortman and Dunkel-Schetter victimization model applied better to interactions with friends and acquaintances than to interactions with close family members. In addition, support was found to be partially dependent on the source: Particular actions were perceived to be helpful from some but not other network members. Implications for theory and research on social support are discussed. 相似文献
797.
Experiments investigated the impact of message elaboration on attitude change-message recall correspondence when attitude change occurs in an on-line (as attitude-relevant information is received), or memory-based (on the basis of retrieved attitude-relevant information) fashion. In 2 experiments, Ss' processing goals were manipulated to increase or inhibit on-line change and message elaboration. As predicted, Ss reported postexposure attitudes more rapidly in on-line vs memory-based conditions. Decreased message elaboration increased attitude-recall correspondence, regardless of when attitude change occurred. Increased elaboration produced elaboration-attitude judgment correspondence. Results suggest that recall of message content will best predict persuasion when message content is encoded free of elaborations, regardless of when attitude change occurs. 相似文献
798.
Expectancy models of alcohol use 总被引:4,自引:0,他引:4
The primary goal of the present article is to compare expectancy models with competing attitude models of alcohol use. First, several methodological issues in expectancy research were addressed, to more adequately compare the theoretical models. Study 1 examined the effect of possible self-report biases on associations among expectancy constructs and alcohol use. In Studies 2 and 3, the basic distinction between general factors of positive and negative alcohol expectancies was investigated in both cross-sectional and prospective models. Alternative predictions that were based on competing expectancy and attitude theories were evaluated primarily in Study 3. Results from these studies supported the validity of the expectancy constructs and the proposed distinctions among expectancy and attitude constructs-in terms of strong discriminant validity, absence of self-report bias, and differential prediction of alcohol use. Furthermore, the findings favored certain expectancy models over alternative attitude models of alcohol use, reaffirming the usefulness of the expectancy framework. 相似文献
799.
The fleeting gleam of praise: cognitive processes underlying behavioral reactions to self-relevant feedback 总被引:1,自引:0,他引:1
W B Swann J G Hixon A Stein-Seroussi D T Gilbert 《Journal of personality and social psychology》1990,59(1):17-26
We propose that a preference for favorable social feedback (i.e., self-enhancement) requires only that feedback be characterized as favorable or unfavorable but that a preference for self-confirming feedback (i.e., self-verification) is based on a more elaborate set of cognitive operations that requires both the characterization of feedback and a subsequent comparison of that feedback to a representation of self stored in memory. Study 1 set the stage for testing this hypothesis by showing that depriving people of processing resources interfered with their tendency to access their self-conceptions. In Studies 2 and 3, participants who were deprived of resources preferred the favorable, self-enhancing evaluator, whereas control participants displayed a preference for the self-verifying evaluator, even if that evaluator was relatively unfavorable. 相似文献
800.
Processing of persuasive in-group messages 总被引:3,自引:0,他引:3
Two studies investigated the processes mediating the persuasive impact of messages representing in-group opinions. In the 1st study, subjects read either a strong or a weak message attributed to either an in-group member or to another group. Subjects were more persuaded by a strong message from the in-group than a weak one, suggesting content-focused processing of the in-group message. Subjects were equally unpersuaded by either a strong or a weak message from the other group, and showed little sign of message processing. In the 2nd study, Ss listened to in-group or other-group messages about issues that varied in their relevance to in-group membership. When the issue was relevant to the in-group, subjects were persuaded by a strong message from the in-group, unpersuaded by a weak message from the in-group, and equally unimpressed by strong and weak messages from the other group. When the issue was irrelevant to the in-group, subjects accepted the position advocated by the in-group regardless of message quality, and again ignored messages from the other group. These results suggest that increased message processing, and not merely the impact of source persuasion cues, can underlie in-group-mediated attitude change. 相似文献