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981.
OBJECTIVES: This research examines the extent to which people accurately report some of the external influences on their food intake. DESIGN: In two studies, specific factors (the presence and behavior of others) were manipulated in order to influence the amount of food that individuals consumed. MAIN OUTCOME MEASURES: The main outcomes of interest were participants' spontaneously generated explanations for their food intake (Study 1; n = 122), and their ratings of the importance of several potential determinants of food intake (Study 2; n = 75). RESULTS: In Study 1, there was high concordance between the amounts eaten by members of a dyad, but very few participants indicated that they were influenced by their partner's behavior; they instead identified hunger and taste as the primary determinants of intake. Study 2 showed that participants' intake was strongly influenced by the behavior of others, but people rated taste and hunger as much more important influences on their intake. CONCLUSIONS: If external environmental factors influence people's food intake without their awareness or acknowledgment, then maintaining a healthy diet can be a challenge, with long-term consequences for health and well-being.  相似文献   
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983.
This article addresses the ability of Parallel Distributed Processing (PDP) networks to generate stagewise cognitive development in accordance with Piaget's theory of cognitive epigenesis. We carried out a replication study of the simulation experiments by McClelland (1989) and McClelland and Jenkins (1991) in which a PDP network learns to solve balance scale problems. In objective tests motivated from catastrophe theory, a mathematical theory of transitions in epigenetical systems, no evidence for stage transitions in network performance was found. It is concluded that PDP networks lack the ability to recover the positive outcomes of analogous catastrophe analyses of real cognitive developmental data. In an attempt to further characterize the learning behaviour of PDP networks, we carried out a second simulation study using the discrimination-shift paradigm. The results thus obtained indicate that PDP learning is compatible with the learning of stimulus-response relationships, not with the acquisition of mediating rules such as conceived in (neo-)Piagetian theory. In closing, we speculate about the feasibility of simulating stagewise development with alternative network architectures.  相似文献   
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985.
This article challenges Block's ‘overflow argument’ for the conclusion that phenomenal consciousness and access‐consciousness are distinct. It shows that the data can be explained just as well (or better) in terms of a distinction between contents that are made globally accessible through bottom–up sensory stimulation and those that are sustained and made available in working memory through top‐down attention.  相似文献   
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The risk of violent behavior is known to be higher for patients who suffer from a severe mental disorder. However, specific prediction tools for clinical work in prison psychiatry are lacking. In this single-center study, two violence risk assessment tools (Forensic Psychiatry and Violence Tool, “FoVOx,” and Mental Illness and Violence Tool, “OxMIV”) were applied to a prison hospital population with a primary psychotic or bipolar disorder and subsequently compared. The required information on all items of both tools was obtained retrospectively for a total of 339 patients by evaluation of available patient files. We obtained the median and inter-quartile range for both FoVOx and OxMIV, and their rank correlation coefficient along with 95% confidence intervals (CIs)—for the full cohort, as well as for cohort subgroups. The two risk assessment tools were strongly positively correlated (Spearman correlation = 0.83; 95% CI = 0.80–0.86). Such a high correlation was independent of nationality, country of origin, type of detention, schizophrenia-spectrum disorder, previous violent crime and alcohol use disorder, where correlations were above 0.8. A lower correlation was seen with patients who were 30 years old or more, married, with affective disorder and with self-harm behavior, and also in patients without aggressive behavior and without drug use disorder. Both risk assessment tools are applicable as an adjunct to clinical decision making in prison psychiatry.  相似文献   
990.
A prospective design was used to explore the efficacy of 6 factors (e.g., intentions) to predict the number of future blood donations in an initial sample of 630 blood donors. Differential predictions are made for the roles of past behavior and intentions with respect to occasional (4 or fewer previous blood donations) and regular (5 or more previous blood donations) blood donors. Intentions were predictive for occasional donors, and past behavior was predictive for regular donors. Furthermore, for regular donors only, an inverted U-shaped curve explained the relationship between past behavior and future behavior. Finally, it is reported that observing others fainting produces a reduction in the number of future donations for occasional donors. The theoretical and practical implications of these findings are discussed.  相似文献   
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