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51.
Cross-correlation and most other longitudinal analyses assume that the association between 2 variables is stationary. Thus, a sample of occasions of measurement is expected to be representative of the association between variables regardless of the time of onset or number of occasions in the sample. The authors propose a method to analyze the association between 2 variables when the assumption of stationarity may not be warranted. The method results in estimates of both the strength of peak association and the time lag when the peak association occurred for a range of starting values of elapsed time from the beginning of an experiment. 相似文献
52.
Radu Negoescu Oana Istrâtescu Mihaela Dincâ-Panaitescu Şerban Dincâ-Panaitescu Alin Achim 《Integrative psychological & behavioral science》2002,37(2):151-160
Step 1
Preliminary MANOVA/ANOVA showed significant effects on the ensemble of spectral variables of every single factor (status: normal or patient group; intervention; gender) with no significant factor interactions. Significant effects of intervention or status on main RR spectral variables and on a few QT spectral variables were also documented.Step 2
Non-parametric tests showed that diabetics had (mildly to moderately) shorter mean RR, while their RR-LF was always singificantly lower than those found in normals—a difference propagated to QT-LF but not to idioventricular QT-LF. In the intra-group there were similar responses to interventions except stress with respect to mean RR. Consistent reduction in RR-LF under moderate or no change in mean RR suggests vagal down-regulation that, judging by idioventricular QT-LF showing, goes perhaps before a similar process with sympathetic control of ventricles. This phase delay may introduce an early arrhythmic risk worth dealing with in secondary prevention. 相似文献53.
15名被试在摄人酒精BAL≤0.5‰前后的四个时段内接受一套简单的运算操作任务,近2/3被试的认知一操作能力显示受酒精影响发生变异:酒后30分钟操作时间延滞,至60分钟更具显著性;同时,操作错误亦大幅上升,但变化趋势不同于操作时间。酒精干扰呈现认知“近视”与“远视”的迹象。 相似文献
54.
Two experiments with the Stroop paradigm were conducted to investigate the role of phonological codes in access to the meaning of Chinese characters. Subjects named the ink color of viewed characters or color patches. Key items were color characters, their homophones with the same tone, homophones with different tones, and semantic associates. Apart from finding the usual Stroop interference effect, homophones produced significant interference in the incongruent condition, provided that they had the same tone as the color characters. The interference effect from homophones, however, was significantly smaller than that from color characters. Semantic associates generated an interference effect in the incongruent condition, an effect of the same magnitude as the effect from the same-tone homophones. Finally, in the congruent conditions, all the key items yielded facilitations compared to neutral controls, though the facilitation from color characters was larger than the facilitations from other types of characters. These findings suggest that phonological codes in Chinese are activated obligatorily and provide early sources of constraint in access to meaning. 相似文献
55.
Previous studies have found that subjects diagnosed with verbal auditory agnosia (VAA) from bilateral brain lesions may experience difficulties at the prephonemic level of acoustic processing. In this case study, we administered a series of speech and nonspeech discrimination tests to an individual with unilateral VAA as a result of left-temporal-lobe damage. The results indicated that the subject's ability to perceive steady-state acoustic stimuli was relatively intact but his ability to perceive dynamic stimuli was drastically reduced. We conclude that this particular aspect of acoustic processing may be a major contributing factor that disables speech perception in subjects with unilateral VAA. 相似文献
56.
In this paper, we discuss the weakness of current action languages for sensing actions with respect to modeling domains with
multi-valued fluents. To address this problem, we propose a language with sensing actions and multi-valued fluents, called
AMK, provide a transition function based semantics for the language, and demonstrate its use through several examples from the
literature. We then define the entailment relationship between action theories and queries in AMK, denoted by ⊧AMK, and discuss some properties about AMK. 相似文献
57.
The authors examined how individuals adapt their gait and regulate their body configuration before altering direction during walking. Eight young adults were asked to change direction during walking with different turning angles (0 degree, 45 degree, 90 degree), pivot foot (left, right), and walking speeds (normal and fast). The authors used video and force platform systems to determine participants' whole-body center of mass and the center of pressure during the step before they changed direction. The results showed that anticipatory postural adjustments occurred during the prior step and occurred earlier for the fast walking speed. Anticipatory postural adjustments were affected by all 3 variables (turn angle, pivot foot, and speed). Participants leaned backward and sideward on the prior step in anticipation of the turn. Those findings indicate that the motor system uses central control mechanisms to predict the required anticipatory adjustments and organizes the body configuration on the basis of the movement goal. 相似文献
58.
Xu M Bellezza FS 《Journal of experimental psychology. Learning, memory, and cognition》2001,27(5):1197-1210
Know and remember recognition judgments were made in 2 experiments. In Experiment 1 either 3 (new, know, remember) or 4 (new, guess, know, remember) judgment alternatives were used. Also, the recognition test was either immediate, delayed 2 days, or delayed 1 week. In Experiment 2 the proportion of test items that were studied items was either .20, .50, or .80. Predictions were made from 2 multimemory theories regarding how proportions of know and remember judgments would change with these manipulations. Predictions were also made from 2 detection theories regarding the values of memory sensitivity and judgment criteria. The results supported the revised detection theory, which assumes unequal variances for studied and unstudied items, more than the multimemory theories. Furthermore, general processing tree versions of the 2 multimemory models were created including guessing processes. These extended models were shown to be inadequate in accounting for the data from the 2 experiments. 相似文献
59.
60.