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61.
The validity of maternal self-reports about their parenting behaviour is evaluated with two studies. In both studies, the mothers were observed shopping in the supermarket with their 2-year-old children. One week later they responded to multiple choice questions on a computer that simulated the experience of shopping with their children. The exact agreement between the two types of data was then assessed. The results from the first study involving 28 mothers revealed some agreement, although it was generally low. In an effort to increase the level of agreement, the computer simulation was revised to allow multiple responses and to clarify some of the simulation vigenettes. A replication study resulted in a considerably higher level of agreement for 22 mothers. Implications of this method for researchers and practitioners are discussed. 相似文献
62.
A structural analysis of the problem behaviors of 32 adults with mental retardation living together in a residential facility showed that a disproportionate number of these behaviors were associated with a period of time scheduled for leisure activities. A staff management program was implemented during this time which included activity and staff scheduling, staff inservice training, and staff performance monitoring and feedback. The results showed an 83% decrease in problem behaviors when the program was implemented during the leisure period and no decrease in problem behaviors during adjacent time periods where the program was not utilized. Follow-up assessments indicated maintenance of these decreased levels of behavior at 3 and 6 months. It was concluded that this approach of combining a structural analysis with staff management procedures was effective in reducing a high level of problem behavior in a residential setting. The results are discussed with regard to pragmatic strategies for the pretreatment analysis of problem behaviors in residential settings, and the role of organizational behavior management techniques in habilitative programing for individuals with behavior disorders. 相似文献
63.
64.
As part of a program to improve maternal and infant health in New Jersey, the Robert Wood Johnson Foundation has funded seven regional consortia throughout the State. One of the goals of the Northern New Jersey Regional Consortium is to provide a comprehensive educational program for ambulatory care staff. An outreach education team was established that includes a perinatal nurse educator, a neonatal nurse educator, a nutritional counselor and a genetic counselor. Many issues in genetics can be initially addressed by the ambulatory care provider. A good understanding and awareness of the impact of genetic issues in patient care is needed to enhance the ability to recognize patients needing special services. Early assessment of possible risk for developmental disabilities can lead to appropriate comprehensive care and improved pregnancy outcome. Regular in-service programs, addressing the way heredity contributes to developmental disorders, the latest techniques used in genetics and the available management programs, can be provided. The present study is an evaluation of the effectiveness of the program. 相似文献
65.
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
66.
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
67.
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
68.
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
69.
Anthony Spirito James Overholser Lori J. Stark 《Journal of abnormal child psychology》1989,17(2):213-221
This study investigated the most common precipitants of adolescent suicide attempts and the strategies used to cope with such problems. Adolescent suicide attempters were compared with both distressed and nondistressed nonsuicidal adolescents on problems reported and coping strategies utilized. All three groups reported four problems as occurring most frequently: school, parents, friends, or boyfriend/girlfriend. The suicide attempters and distressed controls reported problems with parents more frequently than did nondistressed controls, while this latter group reported problems at school more frequently than did suicide attempters or distressed controls. Suicide attempters used social withdrawal, problem solving, and emotional regulation more than did nondistressed controls, but not more frequently than distressed controls. Distressed controls used wishful thinking and resignation more than did suicide atempters. Results are discussed in terms of the similarities between suicide attempters and nonsuicidal distressed adolescents and the need to more closely investigate specific subgroups of suicide attempters. 相似文献
70.