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961.
This study evaluated the effectiveness of the Primary Mental Project (PMHP), a program for early detection and prevention of school adjustment problems. Pre- and postprogram assessments were done with 215 primary-grade children seen in PMHP, usig teacher ratings of problem behaviors and competencies, and child-aide ratings of problems. School mental health professionals judged educational and behavioral changes in project children during the year. Significant across-the board improvements were found on all criterion measures. Modest intercorrelations among criterion change estimates suggested that the observed changes were due to program, rather than halo, effects. PMHP children also improved significantly more than matched, retrospective controls.  相似文献   
962.
A series of studies investigating the psychometric and conceptual properties of the Survey of Ethical Attitudes (SEA), a paper-and-pencil measure of moral reasoning, is reported. The results of these studies indicate that the scale is clearly susceptible to the influence of response dissimulation in the form of both role-playing and impression management, and is also confounded with sources of stylistic variance in the form of social desirability. Previous proposals concerning the relationships among moral development, moral reasoning, and personality structure are reviewed in light of these findings, and an alternative conceptualization of the measure in terms of political and social attitudes is offered.  相似文献   
963.
This study compared two levels of syntactic encoding with respect to their effect on aphasics' auditory comprehension. The same informational content was presented either as an embedded sentence or as two contiguous simplé propositions. A similar contrast was utilized to compare sentences containing relational terms of time, comparison, instrumentality, as well as sentences involving conjunction reduction, with parallel messages expressed in expanded, simplified form. A picture-verification paradigm was used. Comprehension was significantly enhanced only in the case of embedded sentences, with a tendency for Broca's aphasics to show the maximum effects.  相似文献   
964.
According to logical learning theory, a reinforcement involves the extension of meanings predicated by subjects who are asked to perform in a learning task. Based on this theoretical position, it is predicted that subjects who are administered a reinforcement following their successful anticipation of the second member of a paired-associates unit will acquire their liked trigrams more readily than their disliked trigrams (mixed lists). Conversely, it is predicted that subjects who are reinforced following their incorrect anticipations of the second paired-associates member will acquire their disliked trigrams more readily than their liked. College students (divided equally by sex) were exposed to one of three reinforcement conditions: positive reinforcement, negative reinforcement, and no reinforcement (control). Trigrams reliably rated for likability by each subject were used as learnable materials. Although the control condition did not perform as expected, the remaining experimental conditions support the hypotheses.  相似文献   
965.
Metacontrast masking occurs both at the fovea and in the retinal periphery; foveally, the smallest stimulus elicited the strongest masking, whereas peripherally the reverse was the case. An analysis of variance showed a significant size effect, eccentricity effect, and size-eccentricity interaction. As stimulus size increased, the stimulus onset asynchrony of maximum masking shifted to greater values. Both foveal metacontrast and peak shifts contradicted predictions made by the hypothesis that metacontrast is mediated by an interaction of sustained and transient channels in the visual system. The data are consistent, however, with a lateral inhibitory model of metacontrast masking and stimulus coding.  相似文献   
966.
The subjective intensity of one taste quality can be increased by prior exposure of the tongue to a different taste quality stimulus. This phenomenon, called cross-enhancement, may be the result of interactions among the physiological mechanisms that code taste quality. Another possible explanation is that the water solvent of the second stimulus acquires a taste after exposure of the tongue to the first stimulus. This water taste could add to the taste of the solute in the second stimulus and result in an increase of its subjective intensity. A third possibility is that taste receptors on the tongue may be sensitized by exposure to a taste stimulus. Using a small number of highly trained subjects, we have demonstrated that sucrose can enhance the intensity of an acid taste on the single papilla. Neither water taste nor sweet taste system activation played any role in the mediation of this enhancement. Through a series of experimentally derived inferential steps, we conclude that this phenomenon depends on the removal of protons from the acid receptors. In addition, we have demonstrated in the single papilla, that suppression of the acid taste when in mixture with sucrose can occur without sweet system activity. We conclude that sugars, through their capacity to bind protons, act to reduce the availability of protons to the acid receptors.  相似文献   
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Salt taste detection: an R-index approach to signal-detection measurements   总被引:1,自引:0,他引:1  
The R-index approach to the signal-detection P(A) index of sensitivity was used to measure taste sensitivity to NaCl solutions. The R-index is the predicted probability of the correct choice of a signal, for a given signal-noise pair. For flow-wise and sipwise presentation, R-indices did not fluctuate significantly, provided subjects could not see the stimuli yet to be presented, indicating a lack of systematic sensitivity drift. The simultaneous measurement of more than one signal strength with reference to a common noise stimulus was seen to be a viable and sensitive procedure. Comparison of flow-wise and sipwise presentation of stimuli using R-indices, indicated that the former elicited greater subject sensitivity to NaCl taste.  相似文献   
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