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991.
In a transfer-of-control experiment with rats, Pavlovian CSs were tested for the specificity of their effects. The instrumental behavior consisted of a discriminative, conditional two-lever choice task in which qualitatively different appetitive reinforcers were contingent upon the two correct choices. In a Pavlovian phase, subjects experienced conditioning to establish either a CS+ or CS? for one reinforcer or a CS+ or CS? for the other reinforcer. Finally, in a test, these CSs were presented when there was the opportunity to make choice responses. The CS+s evoked choices of the lever which had eventuated in the reinforcer that had served as the Pavlovian US, while the CS?s showed only a slight tendency to evoke the other choice responses. When the CSs were compounded with the original SDs, the CS+s had little effect upon the vigor of responding while the CS?s reduced the vigor of responding to the SD for the reinforcer that was the same as the US used in establishing the CS?. The results are discussed in terms of associative mediational theory and the reinforcer specificity of Pavlovian conditioned excitation and inhibition.  相似文献   
992.
993.
The effects of family size on the perception of three abstract rooms that differed in social and spatial density were studied. The rooms were rated on the dimensions, evaluation, spirituality, activity, and aesthetic appeal. Of the 48 subjects half were from large families with six or more members, and half were from smaller families. Family size had no effect on the perception of the rooms. The room low in spatial density was perceived most favorably, and there was no difference in the perception of a room high in social density and one high in spatial density.  相似文献   
994.
Conclusion Although RSDT is a relatively new form of therapy, we believe there is reason for great optimism regarding the efficacy of the RSDT model. Communications from our colleagues using the model in a variety of settings have been very favorable. We believe the experimental studies that have been conducted on the RSDT model demonstrate that it has generated significantly better outcomes when compared with other therapeutic models and those results obtained from no therapy controls. We think the effectiveness of RSDT has been admirably demonstrated through comprehensive research designs In comparison with outcome studies conducted on other forms of therapy. We look toward the future with optimism as more practitioners begin to use the RSDT model and additional evaluation studies are conducted.  相似文献   
995.
996.
Incest is a major mental health problem, in terms of both prevalence and morbidity. Father-daughter incest constitutes the majority of reported cases. The possibility of incest should be considered in a family which includes a violent father, a disabled mother, a child in an adult maternal role, or an acting out adolescent girl. Intervention requires recognition of the criminal and addictive aspects of the father's behavior. Active cooperation between mental health professionals and mandated child protective and law enforcement agencies is necessary for effective treatment. Group therapy and affiliated self-help programs appear to be the treatment modality of choice. Rehabilitation of the family is based upon restoration of the mother-daughter bond as a guarantee of safety for the child.  相似文献   
997.
Many basic psychophysical functions offer promise as clinical tests of vision. Here, we discuss problems that one encounters in the clinical setting, how one identifies a psychophysical test for potential clinical development, and an orderly approach to development of suitable test paradigms. Parameters are selected which are relatively insensitive to variables encountered in the field (clinic) in a normal population, but which are sensitive to changes in the response system being studied. Initial data on two hyperacuity tests are presented. These tests are adaptations of hyperacuity paradigms (Westheimer, 1979) to a clinical environment. This particular test set offers promise because it exhibits a unique threshold which is dependent upon neural data processing and is relatively independent of retinal image degradation.  相似文献   
998.
Choice reaction latencies were measured at three different a priori probabilities for two stimulus alternatives. Unlike the results of some other studies, the mean latency of a given response was nearly the same whether the response was correct or incorrect. The discriminable stimuli were a 1000- or a 1700-Hz tone presented at 70 dB SPL. Latencies and standard deviations, based on about 17,000 observations, are reported for three observers. The data are compared with predictions of the optimum sequential model of Wald and Stone and two modifications of that random-walk model, one proposed by Link and Heath and the other proposed by Laming. Fast-guess analyses were also carried out. The three-parameter version of either the sequential or the modified random-walk models provided reasonably accurate predictions of the mean data for each observer. The parameters estimated by the fast-guess analysis were unrealistic. There are three obvious differences between this experiment and most previous choice reaction-time experiments. First is stimulus modality#x2014;we used an auditory signal, whereas most of the previous studies used a visual signal. Second, the observers practiced more in this experiment than in most previous experiments. Finally, there was a random foreperiod with a heavy penalty for anticipations. One or more of these factors is the probable reason for the discrepancy between our results and those of previous studies.  相似文献   
999.
1000.
Interpretations regarding the effects of exogenous and endogenous variables on endogenous variables in linear structural equation systems depend upon the convergence of a matrix power series. Convergence depends upon the eigenvalues of the structural coefficient matrix. The test for convergence developed by Jöreskog and Sörbom is shown to be only sufficient, not necessary and sufficient.  相似文献   
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