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981.
The current studies were designed to investigate the influence of variations in type of school setting on the development of role-taking skills and ethnic identity. We were interested in groups of school children in grades 1 to 5 inclusive from three different types of language programs: (1) instruction in the native language (English in this case); (2) total instruction in a second language (French); and (3) partial instruction in a second language (French). All children were native-English speaking, and came from perdominantly middle class families with monolingual English-speaking parents. The children from each program were equated at each grade level on age, and verbal and non-verbal I.Q. It was expected that (1) children in the second language programs would develop identity with their native language reference group later and less consistently than children in the native language programs; because (2) the second language children would identify more with the second language ethnic group; (3) the second language children would be able to understand at an earlier grade level than the native language group the principle of reciprocity in role-taking; and (4) these difference would be more pronounced for the totally than for the partially immersed second language children. The children were required to rate a number of ethnic dolls on a 20 point rating scale according to (1) how much each would be desired as a personal friend, (2) how much each would be desired as a friend for a member of another specific ethnic group, and (3) how similar each doll was to the child. The results indicated general support for hypotheses (1), (2) and (4), particularly among the primary school samples (1, 2), but a lack of support for hypothesis (3). These results demonstrate the influence of socio-cultural factors on the development of ethnic identity and ethnic role-taking skills. 相似文献
982.
C G Gross 《Journal of comparative psychology (Washington, D.C. : 1983)》1978,92(6):1095-1109
Ablation of inferior temporal cortex in the rhesus monkey produces a visual discrimination learning deficit. The severity of this deficit has often been found to be a function of task difficulty. This report concerns a type of visual discrimination problem that, although difficult, is not sensitive to inferior temporal lesions. Monkeys with anterior, posterior, and complete inferior temporal lesions were repeatedly unimpaired or only slightly impaired in learning to discriminate a pattern from the same pattern rotated 90 degrees or 180 degrees; yet they were very severely impaired in learning equally or more difficult discriminations of two different patterns. This demonstration that discrimination of orientation of patterns is relatively spared after inferior temporal lesions helps specify the pattern-recognition processes that require inferior temporal cortex. 相似文献
983.
The development of children's dimensional coordination was investigated using kindergarten, second, fourth, and sixth grade subjects (Ages 5, 7, 9, and 11 years, respectively), and an adult sample, by means of a perceptual estimation task requiring the subjects to match in total area a stimulus rectangle to an adjustable square stimulus. The problem was formulated using information integration theory, and the procedures and techniques of functional measurement were used in the analysis. Dimensional coordination was found to develop from a stage of total centration on one dimension to a stage of total decentration with equal weighting applied to both dimensions.Contrary to extant hypotheses, the vertical dimension was not the salient dimension for single dimension centerers. Rather, the spatial axis on which the compared-objects were placed determined the displacement of attention. When this frame of reference effect was controlled, the longer of the two dimensions was the salient dimension for centering subjects. 相似文献
984.
Responding maintained under fixed-interval and fixed-time schedules of electric shock presentation 总被引:1,自引:1,他引:0 下载免费PDF全文
Malagodi EF Gardner ML Palermo G 《Journal of the experimental analysis of behavior》1978,30(3):271-279
Following initial histories under a schedule of electric shock postponement, lever pressing in squirrel monkeys was maintained under fixed-interval and fixed-time schedules of electric shock presentation. No difference in either rate or pattern of responding was obtained when these schedules were presented as components of a multiple schedule. When they were presented singly for long periods of time, the fixed-interval schedule consistently maintained a higher response rate than the fixed-time schedule. The pattern of responding under both schedules was similar, typically consisting of a pause at the beginning of each interval followed by either a steady or a positively accelerating rate of responding. The results suggest that the response-shock dependency is of critical importance in the maintenance of high rates of responding under schedules of electric shock presentation, and support the general view that such responding may be conceptualized as operant behavior under control of many of the same variables that control responding under comparable schedules of food or water reinforcement. 相似文献
985.
White KG 《Journal of the experimental analysis of behavior》1978,29(2):151-160
In Experiment I, hooded rats were exposed to multiple variable-interval schedules of reinforcement in which manipulanda and reinforcement magazines at opposite ends of the experimental chamber were associated with the different components. Time allocated to each component was measured by recording the time spent by the subject in the appropriate half of the chamber. Positive behavioral contrast was observed for the comparison between multiple variable-interval 30-second variable-interval 30-second and multiple variable-interval 30-second variable-interval 90-second conditions for both response frequency and time allocation measures, but not for mean local response rate (response frequency per time allocated to a component). In Experiment II, rats were exposed to multiple variable-time schedules in which reinforcement was response independent. Time allocated to each component was measured for two conditions, multiple variable-time 30-second variable-time 30-second and multiple variable-time 30-second variable-time 90-second. Positive behavioral contrast of time allocation was exhibited. The results indicated that time allocation was differentially sensitive to changes in reinforcement probability, and that behavioral contrast may result from the differential allocation of time to the different components of the multiple schedule. 相似文献
986.
Recently a number of studies have concerned the possible function of rapid eye movement (REM) sleep and the mastery of stress. The present study was designed to explore the possibility that REM sleep might play a function in reducing the potency of a stressful physiological stimulus, thirst, as well as the possibility that such a function might be specific to individuals falling at different points along the field-dependence dimension. While there was no difference between REM deprivation and non-REM awakening nights in subsequent morning thirst, there was a significant interaction between field dependence and night on morning thirst measures for 10 college students. These results are discussed in light of previous work on stylistic differences in dreaming and their possible role in adaptation to stress. 相似文献
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In the first experiment rats were given either 16 or 48 nonrewarded or continuously rewarded trials prior to 24 continuously or partially rewarded trials, followed by extinction. Increased resistance to extinction was found for increasing numbers of nonrewarded trials when they were followed by partial reward, but not when followed by continuous reward. Similarly, more continuously rewarded trials followed by partial reward tended to increase resistance to extinction. Because of the theoretical importance of the effect of continuous reward followed by partial, a second experiment was performed where the range of the number of continuously rewarded trials was extended to 0, 48, and 96. Contrary to many theoretical predictions, resistance to extinction increased as a function of increasing amounts of continuous reward. 相似文献