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21.
The peak procedure was used in two experiments to study pigeons' ability to time multimodal events. In the first experiment, birds were trained to time a single event consisting of a 9-s tone or light followed by a 21-s fixed interval associated with a signal of light or tone (signal of the other modality). On occasional empty trials, different lengths of the first signal were followed by a long period of the second signal. Peak response times as a function of the duration of the first signal were linear and had a slope of close to one in all birds. This indicates that the birds were timing only the second signal. In a second experiment, two complex events were used in training. One consisted of a 9-s tone or light followed by a 21-s fixed interval associated with a light or tone. The other consisted of a 21-s tone or light followed by a 9-s fixed interval associated with a light or tone. Different durations of the first signal were again used on empty trials. Peak response times as a function of the duration of the first signal were again linear in all birds. The slope of the function was less than one but greater than zero for 3 birds. This indicates that these birds were partly timing the entire complex event of 30-s duration and partly timing only the second signal of the event. A model is proposed in which the bird takes as a criterion for timing a weighted average of different target criteria. Comparisons with the performance of rats are made.  相似文献   
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Given that risk beliefs predict engagement in behaviors to prevent disease, it is important to understand the factors associated with risk beliefs. In the present paper, we conducted path analyses to investigate the associations of belief systems (political orientation and cultural worldviews of individualism and hierarchy) with COVID-19 risk beliefs (i.e., perceived likelihood, perceived severity, and worry about disease; Studies 1 and 2), and the indirect effect through trust in information sources in these relationships (Study 1). Two online panels of U.S. adults were surveyed at three timepoints during the COVID-19 pandemic (Study 1: baseline n = 1,667, 1-year follow-up n = 551; Study 2: n = 404). Results of path analyses indicated that, across studies and timepoints, when controlling for political orientation, trust, and demographic factors, greater individualism had consistent significant direct effects on lower perceived severity and worry about COVID-19, whereas greater hierarchy had consistent significant direct effects on lower perceived severity. However, after accounting for cultural worldviews of individualism and hierarchy (and trust and demographic factors), none of the associations among political orientation and any of the three COVID-19 risk beliefs were significant. The test of indirect effects indicated that individualism and hierarchy were indirectly associated with lower perceived severity of and worry about COVID-19 through less trust. The findings suggest that cultural worldviews of individualism and hierarchy play a role in shaping people's risk beliefs.  相似文献   
24.
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
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Conducted a study of behavior change associated with a street-based AIDS education project targeted to intravenous (IV) drug users in San Francisco. Two cross-sections were sampled from drug detoxification clinics and street locations in 1986 (n = 438) and 1987 (n = 623). Significant increases were reported in the percentage of IV drug users who used bleach to decontaminate syringes, who did not share needles in past year, and in condom use. A significant reduction in an index of the number of needle-sharing partners was reported. Respondents ranked treatment program as most important source of AIDS information prior to implementation of the program, and ranked outreach workers as most important after implementation. Findings suggest that this community-based outreach program had at least some impact on knowledge about AIDS and may have led to reductions in behaviors known to transmit HIV.  相似文献   
26.
人格类型对应激反应影响的实验研究(实验室应激源部分)   总被引:7,自引:0,他引:7  
本研究以EPQ为依据选择高神经质和低神经质2组共24名被试,以有时间压力的心算和复杂辨别反应操作为紧张性刺激,在进行作业的同时记录被试的呼吸频率、呼吸流量、脉率、指端血管容积和皮肤电反应等五项生理指标,并检测尿内儿茶酚胺分泌量。通过对人格类型、作业成绩、作业难度主观评价、紧张性情绪体验,以及对尿内儿茶酚胺分泌量和五项生理指标的综合分析,以研究人格类型对应激反应影响的程度和途径。结果表明,在两组被试作业成绩无显著差异的情况下,在对作业难度主观评价和情绪体验的程度上,高神经质组高于低神经质组。在平静状态下,高神经质组去甲肾上腺素分泌量高于低神经质组;应激状态下,高神经质组的儿茶酚胺反应强度和变化幅度均明显高于低神经质组。高神经质组的五项生理指标均比低神经质组有较大的变化幅度。儿茶酚胺分泌量与脉率有明显的正相关。另外,通过与自然应激源部分的实验结果比较,发现实验室与现场应激的效果基本一致。  相似文献   
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本文依据马克思主义的唯物史观和唯物辩证法原理,从儿童的实际社会生活过程出发,运用系统方法论证了儿童心理发展的动力是主客体之间的结构性矛盾,而由“主体──活动──客体”三项格式构成的反馈回路系统则是心理发生发展的动力场。本文还运用儿童心理发展的控制论模型,从活动的机能性方面探讨了同化和顺应之间的平衡化动力机制,揭示了主客体之间矛盾运动的原理和过程;平衡化机制是受社会文化历史的发展规律支配的。  相似文献   
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How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
30.
The present study compared the moderating effect of social support on parental stress variables and mental health among three groups of parents: parents of HBV (Hepatitis B Virus) children who attended the special health kindergarten, parents of HBV children who stayed at home, and parents of healthy children who attended the ordinary kindergarten. These families resided in the city of Guangzhou. A set of questionnaires measuring parental stress and social support were given to the mothers after a one-hour interview. Results showed that parents of HBV children were significantly more stressed and psychologically at risk than parents of healthy children. They also sought help from social resources more often than the parents of healthy children. Parents of healthy children who attended the ordinary kindergarten reported the highest levels of overall social support, i.e. the number of very close friends and relatives with whom they could form close emotional attachments. Although they reported a lower number of acquaintances available, they also reported the most satisfactory relationships with the support provided by their acquaintances, lower levels of stress, fewer somatic problems, more adequate general health, and more perceived meaning in life than did parents of HBV children, and social support is one of the main influences on stress or parental health. The findings call for further research to focus on parents' well-being and social support that is helpful in addressing the needs of the family.  相似文献   
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