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831.
Relatives (N=121) of adult schizophrenia patients were interviewed to investigate predictors of their level of psychological distress and of rejecting attitudes toward the sufferer. The relatives' total stress, particularly that associated with poor communication skills in the sufferer, predicted several measures of their psychological distress, and the same variables plus turbulence of sufferer behavior (i.e., violence and disruptiveness) predicted rejection of the sufferer by the relative. In each case, adequacy of family support moderated the influence of the stressors, although this effect was more marked for distress outcomes than for rejection. The results have important implications for the sorts of professional and peer support which relatives may need to encourage their performance of this potentially burdensome role. In addition, the results fit a classic stress management model and provide a feasible alternative to the Expressed Emotion Model of the relationship between relatives' rejection and patients' illness severity.  相似文献   
832.
833.
Patients with insufficient financial resources place physicians in a conflict of interest between the patients' needs and the financial interests of the physician, other patients, and society. Not only must physicians act ethically, but they must avoid liability for violating their legal duties to their patients. The traditional rules of contract and malpractice law that govern the patient-physician relationship do not provide satisfactory guidelines. Better answers are found in the rules of fiduciary law, but only with regard to direct conflicts between patients and physicians and only at the risk of reducing patient access to care. Certain types of legislative action can resolve these conflicts by altering the traditional legal rules, but care must be taken to preserve patient-physician trust, which the legal rules were designed to enhance.  相似文献   
834.
Research on risk-taking behavior has shown to yield inconsistent findings. Three studies were conducted using four different analysis techniques. The first study used a phenomenological approach and qualitative analysis to gain an understanding of risk-taking. A model of factors relating to risk-taking was developed and tested in a second study. The third study was conducted to develop scales of risk and used magnitude estimation and multidimensional scaling techniques. Results from the studies confirmed the multidimensionality of the construct of risk-taking. Also indicated was a gender difference in risk-taking behavior and perception. These studies expand our knowledge of risk-taking behavior in that 1) a method of categorizing risks was developed, 2) gender similarities and differences in risk-taking were explored, and 3) perceived magnitude and underlying dimensions of risk were developed.  相似文献   
835.
836.
Over the past two decades, homographs have been used in psychological experiments aimed at testing a variety of theoretical issues concerning memory and language. Often, such research requires prior knowledge of the dominance relations among various meanings of the homographs. Previously available homograph meaning norms are limited because they are now more than 10 years old, and they have typically reported only the two most dominant meanings even though many homographs have three or more common meanings. This paper presents normative data on 120 homographs from a relatively large, heterogeneous sample of subjects (N = 100). Meaning dominance was assessed by having subjects write the first definition that came to mind for each homograph. Definition responses were grouped by similarity, and the resulting meaning categories were verified against dictionary meaning classifications. The number of distinct meanings varied from two to six for the homographs investigated, and frequency of response is reported for all definition categories.  相似文献   
837.
Although the Rescorla-Wagner model is widely taught in learning courses, most textbooks present a simplified version that does not contain all of its parameters. On the basis of Rescorla and Wagner 1972) and the Turbo PASCAL program by Lachnit, Schneider, Lipp, and Kimme! (1988), we created a simulation using STELLA-II, an icon-based program by High Performance Systems, Inc. We argue that this simulation facilitates teaching the complete Rescorla-Wagner model. Using trans-switching (Kimmel & Ray, 1978; Lachnit, 1986; Murrin & Kimmel, 1986) as an example, we demonstrate the effectiveness of the STELLA-II version of the Rescorla-Wagner model as a heuristic tool.  相似文献   
838.
A graphical analysis similar to that used by Hinton and Shallice (1991) was applied to the hair cells of a simulated auditory transducer. The graphical analysis made it apparent that there were hair cells that responded to a narrow range of frequencies, as would be predicted by the tonotopic organization of the real physiology. In short, this study demonstrates the efficacy of using graphic techniques to examine the nature of the autopoetic organization of the hidden layer of back-propagation networks.  相似文献   
839.
The neurons of cerebral cortex are largely autonomous and generate activity that is manifested in trains of microscopic axonal action potentials. The neurons interact by sparse but numerous synaptic connections to generate macroscopic dendritic activity patterns that are observed in electroencephalographic (EEG) waves. The macroscopic patterns are constructed by the populations and they shape the output of cortical neurons in parallel arrays. Sensory cortexes receive sensory information in the form of microscopic action potentials, which induce state transitions in population dynamics. Each state transition transforms sensory information to perceptual meaning. The EEG reflects both kinds of activity. The sensory input is accessed by time ensemble averaging, whereas the perceptual output is found by spatial ensemble averaging. Spatial phase gradients in the EEG are useful for identifying EEG segments in a sequence of state transitions in response to sensory input. The rapidity and flexibility with which they take place give strong reason to postulate that the mechanism for the construction of these sequences of patterns is a dynamical system operating in a chaotic domain.  相似文献   
840.
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