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121.
The Children's Depression Index (CDI) was administered to a group of 304 regular school students in Grades 3–12. It was found that 21% of the students reported mild to moderate levels and 7% reported severe levels of depression. Females reported more overall depression than did males. Specific CDI items selected more frequently by females than by males supports previous work suggesting that females tend to internalize difficulties whereas males are more likely to externalize problems. There were no age differences associated with overall depression; however, there were some developmental differences in specific items cited. Finally, “red flags” were identified that may be helpful in spotting children suffering from severe levels of depression. 相似文献
122.
The present study investigated effects of age and instructions on temporal regulations of behavior in children. In the first experiment 4 1/2-year-old and 7-year-old subjects were trained with a DRL (differential reinforcement of low rates) 5-s and a DRL 10-s schedule. Results demonstrate that age and timing performance are related. Seven-year-olds are more efficient than the 4 1/2-year-olds. A striking decline in the 4 1/2-year-old children's capacity to space responses was observed in the DRL 10-s schedule as compared to the DRL 5-s schedule. Analysis of individual performances suggests that the evolution of DRL performance between 4 and 7 years of age depends not only on the development of the capacity to delay responding but also on the acquisition of the ability to represent the reinforcement contingencies, that is, the temporal parameters of the task to oneself. In order to test this hypothesis a second experiment was conducted where instructions to wait between operant responses were given to a group of 4 1/2-year-old subjects at the beginning of a DRL 5-s and a DRL 10-s schedule. The results show that these instructions enhance DRL performance. By directing the 4 1/2-year-old subjects' attention to the temporal requirements of the task, instructions led to efficient performance and accurate timing of responses to the DRL schedule. 相似文献
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