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911.
It is known that electromyostimulation (EMS) alone or superimposed over voluntary contraction (EV) can effectively improve muscle strength. However, the effect of this type of training on the ability to control force production at submaximal levels is unknown. The authors examined the effects of EV training on steadiness in force production of knee extensors and flexors in older adults. Forty participants, including 20 men and 20 women, 60-77 years of age, were randomly allocated into a control group (CG) and an electromyostimulation superimposed over voluntary contraction (EVG) group. The EVG performed 30 bilateral isometric knee extension and flexion contractions per session, 3 training sessions per week, for 6 weeks. The variations in force production, expressed in absolute (standard deviation [SD]) and relative (coefficient of variation [CV]) terms, were assessed in isometric contractions at 5%, 15% and 25% maximal voluntary contraction (MVC) levels. Results indicated that MVC increased in knee extension and flexion in EVG (p < .05) after the training; steadiness CV also improved at 15% MVC in knee flexion (p < .05) but no significant changes were found in knee extension and steadiness SD. The training-induced changes in MVC were not correlated to steadiness CV that might indicate different mechanisms underlying these adaptations. 相似文献
912.
913.
Daily activity levels were investigated as related to sleep quality in young adult college students aged 18 to 30 years. 85 participants (20 men, 65 women) completed the Young Adult Daily Activity Scale (YADAS). This 37-item checklist has 34 items based on focus group discussion points of college students' typical daily activities and three blank items for students to include their daily activities if not in the listing. The tabulation of type and amount of waking daily activities represents a unique measurement of factors that may affect sleep quality. The participants also rated their typical sleep quality using a standard 5-point scale (low indicating poor sleep). Correlations of sleep ratings and activities were not significant. 相似文献
914.
This commentary considers the paper by Furley and Memmert (2010) who sought to test the respective validities of the specific processing and cognitive adaptation hypotheses. That they found no evidence of a difference between experienced basketball players and nonathletes on the Corsi block task, a measure of spatial memory, led them to infer support for the specific processing hypothesis, namely that differences between experts and novices manifest themselves only in processes related specifically to the domain of expertise. An alternative interpretation is offered, indicating possible confounds and referring to recent research that suggests Corsi block and dynamic spatial tasks depend upon different neuronal networks. 相似文献
915.
A quantum probability model is introduced and used to explain human probability judgment errors including the conjunction and disjunction fallacies, averaging effects, unpacking effects, and order effects on inference. On the one hand, quantum theory is similar to other categorization and memory models of cognition in that it relies on vector spaces defined by features and similarities between vectors to determine probability judgments. On the other hand, quantum probability theory is a generalization of Bayesian probability theory because it is based on a set of (von Neumann) axioms that relax some of the classic (Kolmogorov) axioms. The quantum model is compared and contrasted with other competing explanations for these judgment errors, including the anchoring and adjustment model for probability judgments. In the quantum model, a new fundamental concept in cognition is advanced--the compatibility versus incompatibility of questions and the effect this can have on the sequential order of judgments. We conclude that quantum information-processing principles provide a viable and promising new way to understand human judgment and reasoning. 相似文献
916.
Reniers RL Corcoran R Drake R Shryane NM Völlm BA 《Journal of personality assessment》2011,93(1):84-95
Empathy has been inconsistently defined and inadequately measured. This research aimed to produce a new and rigorously developed questionnaire. Exploratory (n? = 640) and confirmatory (n? = 318) factor analyses were employed to develop the Questionnaire of Cognitive and Affective Empathy (QCAE). Principal components analysis revealed 5 factors (31 items). Confirmatory factor analysis confirmed this structure in an independent sample. The hypothesized 2-factor structure (cognitive and affective empathy) was tested and provided the best and most parsimonious fit to the data. Gender differences, convergent validity, and construct validity were examined. The QCAE is a valid tool for assessing cognitive and affective empathy. 相似文献
917.
918.
Since its establishment, psychology has struggled to find valid methods for studying thoughts and subjective experiences. Thirty years ago, Ericsson and Simon (1980) proposed that participants can give concurrent verbal expression to their thoughts (think aloud) while completing tasks without changing objectively measurable performance (accuracy). In contrast, directed requests for concurrent verbal reports, such as explanations or directions to describe particular kinds of information, were predicted to change thought processes as a consequence of the need to generate this information, thus altering performance. By comparing performance of concurrent verbal reporting conditions with their matching silent control condition, Ericsson and Simon found several studies demonstrating that directed verbalization was associated with changes in performance. In contrast, the lack of effects of thinking aloud was merely suggested by a handful of experimental studies. In this article, Ericsson and Simon's model is tested by a meta-analysis of 94 studies comparing performance while giving concurrent verbalizations to a matching condition without verbalization. Findings based on nearly 3,500 participants show that the "think-aloud" effect size is indistinguishable from zero (r = -.03) and that this procedure remains nonreactive even after statistically controlling additional factors such as task type (primarily visual or nonvisual). In contrast, procedures that entail describing or explaining thoughts and actions are significantly reactive, leading to higher performance than silent control conditions. All verbal reporting procedures tend to increase times to complete tasks. These results suggest that think-aloud should be distinguished from other methods in future studies. Theoretical and practical implications are discussed. 相似文献
919.
920.
Derdikman-Eiron R Indredavik MS Bratberg GH Taraldsen G Bakken IJ Colton M 《Scandinavian journal of psychology》2011,52(3):261-267
Derdikman‐Eiron, R., Indredavik, M. S., Bratberg, G. H., Taraldsen, G., Bakken, I. J. & Colton, M. (2011). Gender differences in subjective well‐being, self‐esteem and psychosocial functioning in adolescents with symptoms of anxiety and depression: Findings from the Nord‐Trøndelag health study. Scandinavian Journal of Psychology52, 261–267. Gender differences in the prevalence of symptoms of anxiety and depression during adolescence are well documented. However, little attention has been given to differences in subjective well‐being, self‐esteem and psychosocial functioning between boys and girls with symptoms of anxiety and depression. The aim of this study was to investigate gender differences in the associations between such symptoms and subjective well‐being, self‐esteem, school functioning and social relations in adolescents. Data were taken from a major population‐based Norwegian study, the Nord‐Trøndelag Health study (HUNT), in which 8984 (91% of all invited) adolescents, aged 13–19 years, completed an extensive self‐report questionnaire. Although prevalence rates of symptoms of anxiety and depression were higher in girls than in boys, a significant interaction between gender and symptoms of anxiety and depression was found in respect of each of the following outcome variables: subjective well‐being, self‐esteem, academic problems, frequency of meeting friends and the feeling of not having enough friends. These interactions indicate that the associations between symptoms of anxiety and depression and lower subjective well‐being and self‐esteem, more academic problems in school and lower social functioning were stronger for boys than for girls. Our findings may contribute to an earlier assessment and more efficient treatment of male adolescent anxiety and depression. 相似文献