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981.
982.
Volume contents     

Volume Contents

Volume contents  相似文献   
983.
A common assumption is that expectancies of reward events in instrumental tasks are established on the basis of Pavlovian conditioning. According to the tandem hypothesis, tested in the four runway investigations reported here employing rats, memories of reward events may serve as the conditioned stimuli eliciting expectancies. In Experiments 1–3, rats were trained under a schedule of partial reward (P), which did not produce increased resistance to extinction, and subsequently shifted to consistent reward (C). According to the tandem hypothesis, the shift to the C schedule should result in increased resistance to extinction if, as hypothesized, under the P schedule the memory of reward, SR, came to elicit the expectancy of nonreward,EN. This hypothesis was confirmed under a variety of conditions. It was shown that increased resistance to extinction could not be attributed to the P schedule alone, to the rats receiving two schedules, P and C, to stimuli other than SR eliciting EN, or to the rats forgetting reward-produced memories when expecting nonreward (Experiment 4). It was shown that the tandem hypothesis could explain the divergent findings obtained in prior studies employing a shift from P to C as well as in the present study.  相似文献   
984.
OBJECTIVE: The purpose of this study is to examine processing of facial emotions in a sample of maltreated children showing high rates of post-traumatic stress disorder (PTSD). Maltreatment during childhood has been associated independently with both atypical processing of emotion and the development of PTSD. However, research has provided little evidence indicating how high rates of PTSD might relate to maltreated children's processing of emotions. METHOD: Participants' reaction time and labeling of emotions were measured using a morphed facial emotion identification task. Participants included a diverse sample of maltreated children with and without PTSD and controls ranging in age from 8 to 15 years. Maltreated children had been removed from their homes and placed in state custody following experiences of maltreatment. Diagnoses of PTSD and other disorders were determined through combination of parent, child, and teacher reports. RESULTS: Maltreated children displayed faster reaction times than controls when labeling emotional facial expressions, and this result was most pronounced for fearful faces. Relative to children who were not maltreated, maltreated children both with and without PTSD showed enhanced response times when identifying fearful faces. There was no group difference in labeling of emotions when identifying different facial emotions. CONCLUSIONS: Maltreated children show heightened ability to identify fearful faces, evidenced by faster reaction times relative to controls. This association between maltreatment and atypical processing of emotion is independent of PTSD diagnosis.  相似文献   
985.
82 9-11-year-old girls were seen in order to study the onset of puberty as represented by breast and pubic hair growth. Girls filled out self-report scales, mothers rated their daughters' breast and pubic hair development using schematic representations of the Tanner stages, and height was measured by a nurse practitioner. Breast growth, but not pubic hair growth, was expected to be associated with a positive body image, positive peer relationships, superior adjustment, and the rating of adult roles as important (marriage, children, and careers). These expectations were confirmed for all but the adult role measures. Controlling for pubic hair growth did not alter the findings for breast development. Associations with height also were examined. Height was linked to superior adjustment and career importance. These findings are discussed in terms of possible roles that different pubertal events may play in the self-definitions of young adolescents as well as the meaning of various physical changes to the girl and to others.  相似文献   
986.
Interactive video combines two well‐established media, video cassette and computer‐assisted learning (CAL), in an attempt to combine the advantages and overcome the deficiencies of both. The paper describes a feasibility study of the medium, using a package that includes a video presentation intercut with interactive CAL programs, on the subject of signals in communication technology. The necessary hardware is described, and two ways of authoring the educational software are compared. Finally, the educational implications of the new medium are discussed together with a consideration of the logistic and administrative problems it presents.  相似文献   
987.
988.
The current study examines the association between parental support and adolescent sleep under varying levels of family stress. Participants included 316 adolescents (Mage = 16.40 years, 43% male) and their parents (Mage = 45.67 years, 91% mothers) from diverse ethnic backgrounds. Both adolescents and parents completed questionnaires and adolescents wore wrist actigraphs and completed self‐reports on their sleep for 7 consecutive days. Results indicated that under contexts of family stress, more parental support was linked to longer sleep duration, less sleep variability, and less time spent awake during the night. Findings suggest that under contexts of family stress, cohesive family relationships may provide a sense of stability and security that is necessary for healthful sleep.  相似文献   
989.
This paper explores the perceived parental influence (PPI) on mathematics learning among over 700 students across three year levels (Years 5, 7, 9) in China and Australia. It was found that the PPI of students was less strong as year levels increased in both countries. Students in China had stronger perceived parental encouragement and higher perceived parental educational expectation than students in Australia. The PPI of students from different home language backgrounds was also investigated. Students in China demonstrated stronger perceived parental encouragement and parental expectation than English speaking students and other language speaking students in Australia, and they also demonstrated stronger perceived parental expectation than Chinese speaking students in Australia, and similar perceived parental encouragement. Within the three groups of students in Australia, Chinese speaking students and other language speaking students demonstrated similar levels of perceived parental encouragement and expectation, but they both demonstrated a higher level of perceived parental encouragement and expectation than English speaking students. Possible reasons for the similarities and differences between the different groups of students were discussed.  相似文献   
990.
Increased use of problem-based approaches to medical education has highlighted the challenges of curricular revision and interdisciplinary development. Venturing beyond disciplinary boundaries can be difficult, despite a desire to create interdisciplinary courses and adopt new ways of teaching. Concept mapping is an effective tool for developing an integrated curriculum. This article includes examples of concept maps that represent an entire veterinary curriculum, specific courses, and case-based exercises. The author argues that concept mapping is a valuable tool for curriculum development of any scope or discipline, but is particularly helpful for creating interdisciplinary courses and case-based exercises.  相似文献   
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