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211.
212.
Chloee K. Poag Ph.D. Robert Cohen Ph.D. Scott W. Henggeler Ph.D. Mary B. Summerville Ph.D. Glen E. Ray M.S. 《Journal of child and family studies》1992,1(3):287-303
The purpose of this research was to examine the relationship between parents' perceptions of marital satisfaction and family stress and their third grade children's classroom behavior. Twenty-one married couples completed questionnaires during home visits. Behavior observations were made from videotapes of children recorded in their classroom during lunch and group academic periods on each of three days. Frequencies of peer interactions, solitary behaviors, and teacher interactions were coded. Regression analyses showed that mothers' level of marital satisfaction (but not fathers') predicted their children's frequency of peer interactions during lunch. Fathers' level of perceived family stress (but not mothers') predicted their children's frequency of peer interactions during lunch. Neither measure for either parent was related to the frequency of peer interactions, solitary behaviors, or teacher interactions observed during the academic sessions. These findings highlight the importance of assessing the potential differential relation of parent variables to children's trans-situational behaviors, and the examination of these variables in relation to different social-environmental contexts in which children participate outside the home. 相似文献
213.
James E. Skinner Mark Molnar Tomas Vybiral Mirna Mitra 《Integrative psychological & behavioral science》1992,27(1):39-53
The application of “chaos theory” to the physical and chemical sciences has resolved some long-standing problems, such as how to calculate a turbulent event in fluid dynamics or how to quantify the pathway of a molecule during Brownian motion. Biology and medicine also have unresolved problems, such as how to predict the occurrence of lethal arrhythmias or epileptic seizures. The quantification of a chaotic system, such as the nervous system, can occur by calculating the correlation dimension (D2) of a sample of the data that the system generates. For biological systems, the point correlation dimension (PD2) has an advantage in that it does not presume stationarity of the data, as the D2 algorithm must, and thus can track the transient non-stationarities that occur when the systems changes state. Such non-stationarities arise during normal functioning (e.g., during an event-related potential) or in pathology (e.g., in epilepsy or cardiac arrhythmogenesis). When stochastic analyses, such as the standard deviation or power spectrum, are performed on the same data they often have a reduced sensitivity and specifity compared to the dimensional measures. For example, a reduced standard deviation of heartbeat intervals can predict increased mortality in a group of cardiac subjects, each of which has a reduced standard deviation, but it cannot specify which individuals will or will not manifest lethal arrhythmogenesis; in contrast, the PD2 of the very same data can specify which patients will manifest sudden death. The explanation for the greater sensitivity and specificity of the dimensional measures is that they aredeterministic, and thus are moreaccurate in quantifying the time-series. This accuracy appears to be significant in detecting pathology in biological systems, and thus the use of deterministic measures may lead to breakthroughs in the diagnosis and treatment of some medical disorders. 相似文献
214.
Quantification of a chaotic system can be made by calculating the correlation dimension (D2) of the data that the system generates
(Packard et al., 1980). The D2 algorithm, however, requires stationarity of the generator, a feature that biological data
rarely reflect (Mayer-Kress et al., 1988). So we developed the “point correlation dimension” (PD2), an algorithm that accurately
tracks D2 in linked data of different dimensions (Carpeggiani et al., 1991). We now present a mathematical argument that,
for stationary data, individual PD2s converge to D2 and we demonstrate that the algorithm rejects contributions made by bursts
of noise. Data were obtained from the surface of the olfactory bulb of the conscious rabbit (64 electrodes, 640 Hz each, 1.3
sec epochs) before and after presentation of a novel or habituated odor. D2 could be calculated in only 1 of 10 novel-odor
trials, whereas PD2 could be calculated in all. Both algorithms indicated that a novel odor evokes a spatially uniform dimensional
increase. The PD2 uniquely exhibited the dimensional decreases that occur during inspiration and the gradients of mean dimension
present during the nonstimulated control state. These control gradients remained unchanged without odor experience, but showed
spatially specific PD2 increases following odor habituation. It is interpreted that, 1) the PD2 issensitive, accurate, and appropriate for dimensional assessment of biological data, 2) that during analysis of unfamiliar information a singleglobal process is transiently evoked in the neuropil, and 3) after experience multiplespatially specific processes tonically map the sites of learning.
Grant Support: National Institutes of Health, HL 31164 and NS27745 相似文献
215.
James A. Bashford Keri R. Riener Richard M. Warren 《Attention, perception & psychophysics》1992,51(3):211-217
Outside of the laboratory, listening conditions are often less than ideal, and when attending to sounds from a particular source, portions are often obliterated by extraneous noises. However, listeners possess rather elegant reconstructive mechanisms. Restoration can be complete, so that missing segments are indistinguishable from those actually present and the listener is unaware that the signal is fragmented. This phenomenon, called temporal induction (TI), has been studied extensively with nonverbal signals and to a lesser extent with speech. Earlier studies have demonstrated that TI can produce illusory continuity spanning gaps of a few hundred milliseconds when portions of a signal are replaced by a louder sound capable of masking the signal were it actually present. The present study employed various types of speech signals with periodic gaps and measured the effects upon intelligibility produced by filling these gaps with noises. Enhancement of intelligibility through multiple phonemic restoration occurred when the acoustic requirements for TI were met and when sufficient contextual information was available in the remaining speech fragments. It appears that phonemic restoration is a specialized form of TI that uses linguistic skills for the reconstruction of obliterated speech. 相似文献
216.
This paper studies a class of infinite-valued predicate logics. A sufficient condition for axiomatizability of logics from that class is given.To the memory of Jerzy Supecki 相似文献
217.
A number of studies have demonstrated stable individual differences in the cues that generate emotions and other feeling states. These differences are assumed to arise from the cues parents use to identify their children's emotional states. As children learn about their own emotional states, they come to rely on these same cues. To test one implication of their view, the facial expressions of children (N=41) were manipulated and their feelings assessed. Some children reported emotions consistent with their expressions, while others reported emotions appropriate to the situation. In a separate procedure, their mothers were asked to identify the emotional states of children whose expressions were inconsistent with an account of their circumstances. Mothers who paid more attention to their children's expressive behavior had children who were more responsive to their own expressive behavior. In contrast, the mothers who were more responsive to situational cues had children whose emotions arose from the situational cues as well.The authors would like to thank numerous teachers and administrators of the Worcester Public School system in Worcester, Massachusetts, for their assistance. 相似文献
218.
Varieties of size-specific visual selection 总被引:1,自引:0,他引:1
Compared time to evaluate stimuli of varying sizes. When Ss expect an upcoming stimulus to be a certain size, response time increases with the disparity between expected and actual size. There are, however, 2 size adjustment processes, and they reflect 2 types of visual selection. In the first, a shape-specific image representation is used to separate a visual object from a superimposed distractor. These representations require the type of slow size scaling demonstrated in imagery experiments. The second size scaling process is faster and not shape-specific. At any given time the visual system is set to process information at a particular scale, and that scale can be adjusted to match an object's size. Because both selection mechanisms depend on size, they probably occur at a relatively low, spatially organized processing level. These findings lead to a new explanation for results that had been taken as evidence for attentional selection at the level of object representations. 相似文献
219.
220.
K H Pollak 《Psychiatrie, Neurologie, und medizinische Psychologie》1989,41(11):664-679
154 autopsy cases of alcoholics (120 men and 34 women) were investigated from a neuropathological viewpoint. In only 19 cases could typical diseases of the nervous system caused by alcoholism be found (Wernicke's encephalopathy, central pontine myelinolysis, Marchiafava-Bignami's disease and disorders of the peripheral nerves and muscles). In comparison liver diseases occurred almost five times more frequently in our own material. Diseases caused by alcoholism of the nervous system, the question of brain shrinkage and its partial reversibility, the up to now not completely known effects on the neurophil and cortical cytoarchitectonic are discussed according to the literature. 相似文献