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102.
    
A hurdle-jump escape response was employed to assess the laboratory rat’s aversion or attraction to different types of conspecific odor. Odorant donor subjects received 112 runway acquisition trials on a continuous reward schedule followed by 32 extinction trials, 112 acquisition trials on a 50% schedule of reward and nonreward followed by 32 extinction trials, or 144 “neutral” trials with no reward in the alley. Different groups of test subjects escaped from odor excreted by odorant subjects on (a) nonrewarded acquisition and extinction trials, (b) rewarded trials during continuous reinforcement, (c) rewarded trials during partial reinforcement, or (d) neutral trials; others escaped from a clean box. The principal findings were: (1) significant aversion to “odor of nonreward” appeared after the donor odorants had received 12 exposures to reward; (2) production of odor of nonreward by odorant subjects changed as a function of training experience with reward; (3) after repeated exposure to odor of nonreward, the escape response habituated; (4) greater or different odor excretion in extinction resulted from subjects trained on a continuous reward schedule than on a partial reward schedule. Relationships of the data to frustration theory were discussed, assuming that inferred differences in production of odor reflect differences in frustration reaction.  相似文献   
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To investigate the role of early regulatory problems (RP), such as problems in feeding, sleeping, and calming down during later development, the association between parent-reported RP at 3 months (no-RP, n = 110; RP, n = 66) and attention to emotional faces at 8 months was studied. Eight-month-old infants had a strong tendency to look at faces and to specifically fearful faces, and the individual variance in this tendency was assessed with eye tracking using a face-distractor paradigm. The early RPs were related to a lower attention bias to fearful faces compared to happy and neutral faces after controlling for temperamental negative affectivity. This suggests that early RPs are related to the processing of emotional information later during infancy.  相似文献   
104.
This longitudinal study evaluated the extent to which maternal responsiveness across early childhood and children's cognitive skills predicted children's 8-year decoding and reading comprehension skills for children who varied in biological risk (term, n = 83; preterm, n = 155). Patterns of maternal responsiveness during infancy (6, 12, and 24 months) and preschool (3 and 4 years) revealed 4 maternal clusters that varied in consistency and level of maternal responsiveness. Although not predictive of decoding skills, the interaction between children's 4-year cognitive ability and maternal responsiveness cluster predicted children's reading comprehension skills at 8 years of age, regardless of risk. Although consistently high levels of maternal responsive parenting across early childhood related to literacy outcomes for all children in the study, responsive parenting had a stronger relation to later reading comprehension skills for children with lower cognitive abilities, particularly when mothers demonstrated high responsiveness in children's infancy.  相似文献   
105.
Reading and Writing - The purpose of this study was to investigate the concurrent relationships between selected teacher-rated executive function (EF) and a comprehensive array of emergent literacy...  相似文献   
106.
OBJECTIVES: To examine the effects of different forms of family violence at two developmental stages by assessing a sample of 110 Israeli children, drawn from the case files of Israeli family service agencies, studied longitudinally in both middle childhood and adolescence. METHODS: Information about the children's adjustment was obtained from parents, teachers, and the children themselves when the children averaged 10.6 and 15.9 years of age using the Child Behavior Checklist (CBCL), Teacher Report Form (TRF), Youth Self-Report (YSR), and Children's Depression Inventory (CDI). Information about the history of family violence was obtained from the mothers, fathers, children, and social workers. RESULTS: The results paint a mixed picture of the effects of family violence on children and adolescents. The relationship between concurrent behavior problems and abuse group varied by informant and study phase, although they were strongest when children were the informants. Predictions regarding the relationship between early abuse and later adjustment were only partially confirmed. Different informants did not agree about which groups of children were most adversely affected, there was little stability over time in the pattern of reported effects, and children were more likely than other informants to report levels of maladjustment that varied depending on recent or concurrent exposure to family violence. Many families changed their abuse status over time, and children who were new victims at follow-up had the most internalizing problems. Girls were found to be at more risk for internalizing and externalizing behavior problems than boys. CONCLUSIONS: Multiple informants are necessary to evaluate and assess the effects of family violence on children's behavior. Younger children may be more susceptible to the effects of family violence than older children, but problems manifest by some children may not carry over to adolescence. Changes in family and parenting practices, as well as in children's capacity to appraise and cope with family violence may help mitigate the adverse effects of family violence.  相似文献   
107.
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   
108.
    
Two experiments investigated kindergarten through fourth-grade children's and adults' (N = 128) ability to (1) evaluate the certainty of deductive inferences, inductive inferences, and guesses; and (2) explain the origins of inferential knowledge. When judging their own cognitive state, children in first grade and older rated deductive inferences as more certain than guesses; but when judging another person's knowledge, children did not distinguish valid inferences from invalid inferences and guesses until fourth grade. By third grade, children differentiated their own deductive inferences from inductive inferences and guesses, but only adults both differentiated deductive inferences from inductive inferences and differentiated inductive inferences from guesses. Children's recognition of their own inferences may contribute to the development of knowledge about cognitive processes, scientific reasoning, and a constructivist epistemology.  相似文献   
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This study was designed to learn if students perceived an interactive computer/videodisc learning system to represent a viable alternative to (or extension of) the conventional laboratory for learning biology skills and concepts normally taught under classroom laboratory conditions. Data were collected by questionnaire for introductory biology classes at a large midwestern university where students were randomly assigned to two interactive videodisc/computer lessons titled Respiration and Climate and Life or traditional laboratory investigation with the same titles and concepts. The interactive videodisc system consisted of a TRS-80 Model III microcomputer interfaced to a Pioneer laser-disc player and a color TV monitor. Students indicated an overall level satisfaction with this strategy very similar to that of conventional laboratory instruction. Students frequently remarked that videodisc instruction gave them more experimental and procedural options and more efficient use of instructional time than did the conventional laboratory mode. These two results are consistent with past CAI research. Students also had a strong perception that the images on the videodisc “were not real” and this factor was perceived as having both advantages and disadvantages. Students found the two approaches to be equivalent to conventional laboratory instruction in the areas of general interest, understanding of basic principles, help on examinations, and attitude toward science. The student-opinion data in this study do not suggest that interactive videodisc technology serve as a substitute to the “wet” laboratory experience, but that this medium may enrich the spectrum of educational experiences usually not possible in typical classroom settings.  相似文献   
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