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931.
Is there a cell-biological alphabet for simple forms of learning?   总被引:5,自引:0,他引:5  
  相似文献   
932.
This paper proposes test statistics based on the likelihood ratio principle for testing equality of proportions in correlated data with additional incomplete samples. Powers of these tests are compared through Monte Carlo simulation with those of tests proposed recently by Ekbohm (based on an unbiased estimator) and Campbell (based on a Pearson-Chi-squared type statistic). Even though tests based on the maximum likelihood principle are theoretically expected to be superior to others, at least asymptotically, results from our simulations show that the gain in power could only be slight.  相似文献   
933.
The effects of tobacco smoking on responses to electrical stimulation were studied according to a Method of Limits (ML) threshold analysis and a Sensory Decision Theory (SDT) analysis. For the ML procedure, Detection Threshold (DT), Pain Threshold (PT) and Tolerance Level (TL) measures were obtained. For the SDT procedure, nonparametric estimates of capacity to discriminate between stimulus intensities (P(A)) and response criterion (B) were calculated. There was no main effect of tobacco smoking on responses to electrical stimulation. Males had consistently higher ML thresholds than females in both the NS and S condition. Males also tended to increase in DT and PT after smoking. From a comparison between the effects of smoking on ML and SDT measures it was suggested that PT is related mainly to sensory factors and TL to response factors.  相似文献   
934.
Asymmetric neural control systems in human self-regulation   总被引:15,自引:0,他引:15  
  相似文献   
935.
The paper contains a detailed study of the St. Pauls' riots of April 1980. Particular attention is paid to the limits of participation in the event and the limits of crowd action. It is argued that these limits show clear social form and cannot be explained in terms of the individualistic theories that dominate crowd psychology. Instead a model of crowd behaviour based on the social identity model is advanced to account for the observations. It is concluded that crowd behaviour is more sophisticated and creative than hitherto allowed and that the neglect of this field should be remedied.  相似文献   
936.
937.
This commentary critically examines two facets of Tracy Llanera's recent book Richard Rorty: Outgrowing Modern Nihilism. First, it considers her interpretation of Richard Rorty's redemptive project. It argues that, while Llanera succeeds in resolving tensions in Rorty's public-private distinction, her account downplays the role of abnormal discourse within projects of self-creation. Second, it raises several questions about Llanera's strategy for situating this redemptive project within debates concerning existential nihilism. On her view, one ought to follow Rorty in addressing the problem of egotism instead of the problem of nihilism, since the former is prior to the latter. But it is not clear who counts as an egotist, or why egotists are especially prone to becoming nihilists. Moreover, there are reasons to think that egotism and nihilism are fundamentally different kinds of problems.  相似文献   
938.
The reinforcer pathology model posits that core behavioral economic mechanisms, including delay discounting and behavioral economic demand, underlie adverse health decisions and related clinical disorders. Extensions beyond substance use disorder and obesity, however, are limited. Using a reinforcer pathology framework, this study evaluates medical adherence decisions in patients with multiple sclerosis. Participants completed behavioral economic measures, including delay discounting, probability discounting, and a medication purchase task. A medical decision-making task was also used to evaluate how sensitivity to mild side effect risk and efficacy contributed to the likelihood of taking a hypothetical disease-modifying therapy. Less steep delay discounting and more intense (greater) medication demand were independently associated with greater adherence to the medication decision-making procedure. More generally, the pattern of interrelations between the medication-specific and general behavioral economic metrics was consistent with and contributes to the reinforcer pathology model. Additional research is warranted to expand these models to different populations and health behaviors, including those of a positive health orientation (i.e., medication adherence).  相似文献   
939.
Previous research has evaluated the effects of prompt rates on the rate of communicative behavior. More recent research has suggested that dense prompting can result in communicative behavior that is more resistant to change. However, existing research has not considered the impact that higher response rates had on reinforcement rate, a variable known to impact response persistence. The current study systematically replicated previous research by evaluating communicative responding in contexts associated with dense- and lean-prompt schedules and extended existing research by (a) holding reinforcement rates similar across the two prompting schedules (lean and dense), and (b) evaluating the persistence of communicative responding in the contexts associated with each prompting schedule. The results for Experiment 1 clearly replicated and extended previous research. The results for Experiment 2 were equivocal and suggested that previous reinforcement history and response class size impacted outcomes.  相似文献   
940.
This review involved a systematic analysis of equivalence-based instruction (EBI) that aimed to improve food-size interventions in diverse populations. Systematic searches identified seven studies published since 2010 that met inclusion criteria. These studies were analyzed according to their participants, design, setting, content taught, training structures, training protocol, testing format, treatment integrity, and outcomes. Results showed EBI procedures for teaching food estimation skills have been mostly implemented with adults. The type of content taught in the identified studies included carbohydrate ranges, portion size with food and non-food items, measuring cups and nutritional content of calories. Majority of included studies used one-to-many training structure and simultaneous protocols for teaching stimulus relations. Five studies completed a generalization probe and three studies reported treatment integrity data. Overall, all participants demonstrated skill acquisition of novel relations between food and portion measurement aides. Recommendations for future research and clinical applications of EBI in teaching food portion estimation are presented.  相似文献   
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