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91.
从信息加工视角探究个体对医疗信息的风险感知过程, 通过医疗信息来源、医疗信息内容与呈现形式和信息加工主体三个方面归纳其影响因素, 并基于经验-分析式加工理论和字面-要义加工理论探讨医疗信息风险感知的认知机制。今后研究可更注重医疗信息风险感知的通用研究与特殊主题研究的平衡、风险感知测量工具的规范性与特异性的结合, 并立足于中国医疗体系建立具有循证依据的预防措施和配套政策。  相似文献   
92.
现代社会生活的生产实践表明,分工是交换的前提,交换是分工的实现,这就是现代社会活动的全部内容和过程。在此事实基础上构建的市场经济体制,其管理理念内含着丰富的伦理意蕴[1]。本文首先分析阐述了市场经济信用体系的建立是市场经济体制内在规律的必然要求,揭示了“信用”是承诺者之间能量均衡与博弈的结果,既具有丰富的道德理性又具有明显的功利要求。文章进而通过对信用体系维护的动力因素及其与市场主体行为的相关性进行比较研究后指出:政府在参与市场经济活动中要坚持“有所为,有所不为”,应把政府置于经济利益之外,使之具有超脱于市场各成员的地位;同时,信用体系的创立和维护并不必然由政府主导,而是市场经济环境中公共合意选择的必然结果。  相似文献   
93.
All languages rely to some extent on word order to signal relational information. Why? We address this question by exploring communicative and cognitive factors that could lead to a reliance on word order. In Study 1, adults were asked to describe scenes to another using their hands and not their mouths. The question was whether this home-made "language" would contain gesture sentences with consistent order. In addition, we asked whether reliance on order would be influenced by three communicative factors (whether the communication partner is permitted to give feedback; whether the information to be communicated is present in the context that recipient and gesturer share; whether the gesturer assumes the role of gesture receiver as well as gesture producer). We found that, not only was consistent ordering of semantic elements robust across the range of communication situations, but the same non-English order appeared in all contexts. Study 2 explored whether this non-English order is found only when a person attempts to share information with another. Adults were asked to reconstruct scenes in a non-communicative context using pictures drawn on transparencies. The adults picked up the pictures for their reconstructions in a consistent order, and that order was the same non-English order found in Study 1. Finding consistent ordering patterns in a non-communicative context suggests that word order is not driven solely by the demands of communicating information to another, but may reflect a more general property of human thought.  相似文献   
94.
The purpose of this study was to determine the effects of teacher feedback delivered via a public address system on the off-task behavior of elementary-school physical education students. A multiple baseline design across three classes was used in this investigation. Results indicated a consistent decline in off-task behavior when the public address feedback system was used.  相似文献   
95.
Pigeons were trained to discriminate 5 mg/kg pentobarbital from saline under concurrent variable-ratio (VR) VR schedules, in which responses on the pentobarbital-biased lever were reinforced under the VR schedule with the smaller response requirements when pentobarbital was given before the session, and responses on the saline-biased key were reinforced under the VR schedule with the larger response requirements. When saline was administered before the session, the reinforcement contingencies associated with the two response keys were reversed. When responding stabilized under concurrent VR 20 VR 30, concurrent VR 10 VR 40, or concurrent VR 5 VR 50 schedules, pigeons responded almost exclusively on the key on which fewer responses were required to produce the reinforcer. When other doses of pentobarbital and other drugs were substituted for the training dose, low doses of all drugs produced responding on the saline-biased key. Higher doses of pentobarbital and chlordiazepoxide produced responding only on the pentobarbital-biased key, whereas higher doses of ethanol and phencyclidine produced responding only on this key less often. d-Amphetamine produced responding primarily on the saline-biased key. When drugs generalized to pentobarbital, the shape of the generalization curve under concurrent VR VR schedules was more often graded than quantal in shape. Thus, drug discrimination can be established under concurrent VR VR schedules, but the shapes of drug-discrimination dose-response curves under concurrent VR VR schedules more closely resemble those seen under interval schedules than those seen under fixed-ratio schedules. Graded dose-response curves under concurrent VR VR schedules may relate to probability matching and difficulty in discriminating differences in reinforcement frequency.  相似文献   
96.
The present paper provides evidence that the processing of verb final clauses proceeds incrementally based on local information that becomes available with each word. The results of three self-paced reading experiments are reported in support of the proposal that NPs in Japanese are associated within clauses before a verb is processed. It is argued that a clause boundary is posited whenever case markers prevent two NPs from being part of the same clause, and slow reading times at the second NP are used as supporting evidence. Moreover, clause boundaries induced by case marking can facilitate processing at later points in the sentence as attested to by faster reading times at relative-clause heads. Contrary to previous findings that argued against a subclass of head-driven parsers, the present results are not easily reconcilable with any type of model that delays parsing decisions until a verb is available in the input sentence.  相似文献   
97.
We investigated crossmodal temporal performance in processing rapid sequential nonlinguistic events in developmentally dyslexic young adults (ages 20-36 years) and an age- and IQ-matched control group in audiotactile, visuotactile, and audiovisual combinations. Two methods were used for estimating 84% correct temporal acuity thresholds: temporal order judgment (TOJ) and temporal processing acuity (TPA). TPA requires phase difference detection: the judgment of simultaneity/nonsimultaneity of brief stimuli in two parallel, spatially separate triplets. The dyslexic readers' average temporal performance was somewhat poorer in all six comparisons; in audiovisual comparisons the group differences were not statistically significant, however. A principal component analysis indicated that temporal acuity and phonological awareness are related in dyslexic readers. The impairment of temporal input processing seems to be a general correlative feature of dyslexia in children and adults, but the overlap in performance between dyslexic and normal readers suggests that it is not a sufficient reason for developmental reading difficulties.  相似文献   
98.
Coney J 《Brain and language》2002,80(3):355-365
Recent neuroimaging studies have revealed neuroanatomical centers of activation that appear to be linked specifically to phonological processes. Furthermore, there is evidence that these centers of activation are more likely to be bilaterally represented in women than in men. However, behavioral evidence of such hemispheric asymmetries or of related sex differences is somewhat inconsistent. Two experiments were carried out to determine whether behavioral correlates of the neuroimaging findings could be demonstrated. The first experiment employed a rhyme-matching task used in a recent neuroimaging study, in which two nonsense words were projected successively to the left or right sides of the visual field. The results indicated that the left hemisphere was superior for this task. An analysis of gender effects, however, revealed that the asymmetry was restricted to men. The second experiment employed a lateralized pseudohomophone detection task that was designed to determine whether the results of the first experiment could be confirmed in the context of a phonological task with a simpler structure. This experiment broadly supported the findings of the first experiment. The results support the specialization of the left hemisphere for phonological processing, and the existence of gender differences with respect to these processes.  相似文献   
99.
Waite TA 《Animal cognition》2002,5(4):209-214
Under the assumption that selection favors minimization of costly errors, erroneous choice may be common when its fitness cost is low. According to an adaptive-choice model, this cost depends on the rate at which an animal encounters the choice: the higher this rate, the smaller the cost of choosing a less valuable option. Errors should thus be more common when interruptions to foraging are shorter. A previous experiment supported this prediction: gray jays, Perisoreus canadensis, were more error prone when subjected to shorter delays to access to food rewards. This pattern, though, is also predicted by an attentional-constraints model. Because the subjects were able to inspect the rewards during delays, their improved performance when subjected to longer delays could have been a byproduct of the experimentally prolonged opportunity for information processing. To evaluate this possibility, a follow-up experiment manipulated both delay to access and whether rewards could be inspected during delays. Depriving jays of the opportunity to inspect rewards (using opaque lids) induced only a small, nonsignificant increase in error rate. This effect was independent of length of delay and so the jays' improved performance when subjected to longer delays was not simply a byproduct of prolonged information processing. More definitively, even when the jays were prevented from inspecting rewards during delays, their performance improved when subjected to longer delays. The findings are thus consistent with the adaptive-choice model. Electronic Publication  相似文献   
100.
Four rats were studied with variants of a progressive-ratio schedule with a step size of 6 in which different terminal components followed completion of the 20th ratio: (a) a reversal of the progression, (b) a fixed-ratio 6 schedule, or (c) extinction. Responding in the progressive-ratio components of these schedules was compared to performances under conventional progressive-ratio baselines. Under baseline conditions, postreinforcement pauses increased exponentially as a function of increasing ratio size, whereas running rates showed modest declines. The procedure of linking the progressive-ratio schedule to the reversed progression or to the fixed-ratio component resulted in decreased pausing. Linking the progressive-ratio schedule to the extinction component had the opposite effect, that of producing weakened progressive-ratio performances as evidenced by increased pausing. Subjects whose responses were reinforced on half of the ratios also showed exponential increases; however, pauses were substantially shorter following ratios on which the reinforcer was omitted. The results suggested that progressive-ratio pausing reflects the influence of remote as well as local contingencies.  相似文献   
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