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951.
Congruency tasks have provided support for an amodal magnitude system for magnitudes that have a "spatial" character, but conflicting results have been obtained for magnitudes that do not (e.g., luminance). In this study, we extricated the factors that underlie these number-luminance congruency effects and tested alternative explanations: (unsigned) luminance contrast and saliency. When luminance had to be compared under specific task conditions, we revealed, for the first time, a true influence of number on luminance judgments: Darker stimuli were consistently associated with numerically larger stimuli. However, when number had to be compared, luminance contrast, not luminance, influenced number judgments. Apparently, associations exist between number and luminance, as well as luminance contrast, of which the latter is probably stronger. Therefore, similar tasks, comprising exactly the same stimuli, can lead to distinct interference effects.  相似文献   
952.
This study aimed to identify the relationship between satisfaction with transitional care and quality of life of chronically ill adolescents over time. This longitudinal study included adolescents with type I diabetes, juvenile idiopathic arthritis (JIA), and neuromuscular disorders (NMD). At baseline 138 respondents (response rate 31 %) filled in a questionnaire and 188 about 1 year later (response rate 43 %). Analysis of variance showed that adolescents with diabetes reported the highest physical quality of life, followed in order by those with NMD and JIA (p?≤?0.01). Adolescents with diabetes reported the highest social quality of life, followed in order by those with JIA and NMD (both at p?≤?0.001). Univariate analyses showed that satisfaction with transitional care at T0 was significantly related to emotional and physical quality of life at T1 (both at p?≤?0.05). At T1, satisfaction with transitional care was significantly related to the emotional, physical, and social domains of quality of life (all at p?≤?0.001). Multiple regression analyses revealed that satisfaction with transitional care at T1 was related to emotional (β -0.20; p?≤?0.05) and social (β -0.35; p?≤?0.01) quality of life domains over time. This indicates that lower gap scores, which measured differences between ‘best care’ and ‘current care,’ are associated with better social and emotional quality of life in this sample of adolescents. Satisfaction with transitional care and social and emotional quality of life are related over time.  相似文献   
953.
First-letter naming was used to investigate the role of phonology in printed word perception in children with and without dyslexia. In 2 experiments, all children showed faster first-letter-naming times in a congruent condition than in an incongruent condition, which suggests that phonology is a fundamental constraint in the printed word perception of readers of all levels and all skills. An explanation in terms of a recurrent network put forward by G. C. Van Orden and S. D. Goldinger (1996) is discussed to account for the apparent paradox in the reading behavior of readers with dyslexia, that is, that in first-letter naming, dyslexic readers appear to show phonological congruity effects, whereas in pseudoword reading, their phonological knowledge appears to be deficient or absent.  相似文献   
954.
Formal definitions are given of the following intuitive concepts: (a) A model is quantitatively testable if its predictions are highly precise and narrow. (b) A model is identifiable if the values of its parameters can be ascertained from empirical observations. (c) A model is redundant if the values of some parameters can be deduced from others or if the values of some observables can be deduced from others. Various rules of thumb for nonredundant models are examined. The Counting Rule states that a model is quantitatively testable if and only if it has fewer parameters than observables. This rule can be safely applied only to identifiable models. If a model is unidentifiable, one must apply a generalization of the Counting Rule known as the Jacobian Rule. This rule states that a model is quantitatively testable if and only if the maximum rank (i.e., the number of linearly independent columns) of its Jacobian matrix (i.e., the matrix of partial derivatives of the function that maps parameter values to the predicted values of observables) is smaller than the number of observables. The Identifiability Rule states that a model is identifiable if and only if the maximum rank of its Jacobian matrix equals the number of parameters. The conclusions provided by these rules are only presumptive. To reach definitive conclusions, additional analyses must be performed. To illustrate the foregoing, the quantitative testability and identifiability of linear models and of discrete-state models are analyzed. Copyright 2000 Academic Press.  相似文献   
955.
This article focuses on the question of why fairness matters to people. On the basis of fairness heuristic theory, the authors argue that people especially need fairness when they are uncertain about things that are important to them. Following terror management theory, the authors focus on a basic kind of human uncertainty: fear of death. Integrating these two theoretical frameworks, it is proposed that thinking about their mortality should make fairness a more important issue to people. The findings of three experiments support the authors' line of reasoning: Asking participants to think about their mortality led to stronger fair process effects (positive effects of perceived procedural fairness on subsequent reactions) than not asking them to think about mortality. It is argued that these findings suggest that fairness especially matters to people when they are uncertain about fundamental aspects of human life such as human mortality.  相似文献   
956.
Immediate affective reactions to outcomes are more intense following decisions to act than following decisions not to act. This finding holds for both positive and negative outcomes. We relate this "actor-effect" to attribution theory and argue that decision makers are seen as more responsible for outcomes when these are the result of a decision to act as compared to a decision not to act. Experiment 1 (N = 80) tests the main assumption underlying our reasoning and shows that affective reactions to decision outcomes are indeed more intense when the decision maker is seen as more responsible. Experiment 2 (N = 40) tests whether the actor effect can be predicted on the basis of differential attributions following action and inaction. Participants read vignettes in which active and passive actors obtained a positive or negative outcome. Action resulted in more intense affect than inaction, and positive outcomes resulted in more intense affect than negative outcomes. Experiment 2 further shows that responsibility attributions and affective reactions to outcomes are highly correlated; that is, more extreme affective reactions are associated with more internal attributions. We discuss the implications for research on post-decisional reactions.  相似文献   
957.
Forty-nine adolescents performed the Wisconsin Card Sorting Test (WCST). A main PCA component of WCST performance was identified as 'efficiency of reasoning'. This factor was related to feedback processing. From the WCST, a perseveration score can be derived. Perseveration is the continued application of a rule, after it has been disconfirmed. We compared more and less perseverating subjects in relation to stimulus-response (SR) time, feedback inspection time and cardiac acceleration and deceleration. Less perseverating subjects responded faster, and had longer and more adaptive inspection times of error feedback. We examined the switch from rule application to rule search, and the difference between correct and error responses. A transient cardiac deceleration at the initiation of rule search was interpreted as a change in supervisory attention. An error-related deceleration to negative feedback was interpreted as a disturbance of higher control processing. Previous trial feedback influenced current processing time, feedback inspection time, and the cardiac acceleration and deceleration responses.  相似文献   
958.
Breathlessness and negative emotions during asthma attacks interact in complex patterns. This study tested the influence of emotional imagery on breathlessness during voluntary breath holding. Adolescents with and without asthma (n = 36 + 36) were assigned to positive imagery, negative imagery, or no imagery. There were four trials with close to thresholds for breath holding combined with imagery. Breathlessness and quality of imagery were measured by the end of breath holding. Additional measures were lung function and anxiety. The results showed that positive and negative imagery were only influencing breathlessness in participants with asthma. Although threshold duration for the groups were not significantly different, participants with asthma reported more breathlessness. The intensity of imagery enhanced breathlessness but diminished the accuracy of symptom perception. Positive imagery diminished breathlessness in participants with asthma, but also the difference in breathlessness between 75% and 95% of threshold duration. Breathlessness did not correlate with lung function, anxiety or other variables. It was concluded that emotional imagery during asthma attacks distracts from accurate introspection or enhances breathlessness, irrespective of anxiety.  相似文献   
959.
Computer-driven systems for constructing composite faces of suspects (E-fit; Mac-a-Mug) have largely replaced mechanical systems (Photofit; the Identikit) in police use, yet little is known of their comparative effectiveness in rendering an accurate likeness. Participants (N = 24) constructed 2 of 4 familiar or unfamiliar faces, for one of which they used Photofit and for the other, E-fit. A likeness of each face was made first under target-absent conditions and then with photographs of the target present. The accuracy of the resulting composites was assessed by familiarity ratings, names elicited, and matching accuracy. The computer-driven system showed consistent superiority only when a familiar face was constructed in the presence of photographs; when participants worked from memory, E-fit was no better than Photofit. The implications of these findings for theories of face retrieval and the operational use of composites are discussed.  相似文献   
960.
All writers produce text content and ideally connect it together according to discourse conventions. We investigate whether a particularly strong discourse convention, the need for causal coherence in narratives, can predict the kind of text writers will produce. Causality has been found to be a significant discourse factor in reading comprehension and hence can be expected to determine also what writers produce during composition. In Experiment 1, writers composed short continuations at various points throughout a simple narrative, whereas in Experiment 2, writers composed continuations to complete several narratives. The results indicate that causality indeed plays a major role in composition. Writers tend to produce new text in such a way that it is causally connected to the prior text. Furthermore, writers favored causal relations of necessity or of necessity and sufficiency while largely avoiding relations of sufficiency alone, which suggests a general discourse constraint to be maximally informative (e.g., Grice, 1975).  相似文献   
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