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991.
Each year, a large number of children change residence and school. This paper examines the social experience of being a newcomer at secondary school, with special reference to the process of adjustment. It is based on a detailed longitudinal case study of 45 newcomers. Each was followed for 12 months, with the main source of data being seven in-depth interviews with each student, backed up by unscheduled interviews, school reports, teacher and peer-group comments and observations. Because the data show extensive similarity in newcomers' experiences-all must deal with a different curriculum, new teachers and the social world of other students-it is possible to construct a general three-stage map of the process of adjustment. This map has important implications for the guidance and counselling of such students.  相似文献   
992.
This paper explores how discoveries and inventions in nine scientific disciplines cluster over time in Western culture. The transhistorical sample consisted of 12,761 major scientific contributions tabulated into 44 time-units (full, half, and quarter centuries) extending from 800 B.C. to 1900 A.D. A factor analysis was executed on the correlations among the nine measures after partialing out third-order polynomial time trends. Three orthogonal factors appeared: concrete (chemistry, physics, and biology), abstract (astronomy and mathematics), and applied (technology, geography, and geology) clusters. Medicine loaded moderately on the concrete and abstract clusters. Three types of explanations were discussed-personological, interpersonal, and sociocultural-with suggestions for how they might be tested.  相似文献   
993.
Two experiments on the role of neophobia in poison-induced aversions to exteroceptive stimuli are reported. In Experiment 1, rats were given either 10 or 25 days of habituation to the test situation prior to conditioning. Those animals with the longer habituation period avoided a complex of novel exteroceptive stimuli while those with the shorter habituation period did not. In Experiment 2 rats initially avoided the more novel of two containers, but gradually came to eat equal amounts from both. A single pairing of toxicosis with consumption from either the novel or the familiar container reinstated the avoidance of the novel container in both cases. The results were discussed in terms of an interaction between habituation and conditioning procedures. It was suggested that previously reported differences between interoceptive and exteroceptive conditioning effects may have been influenced by the differential novelty of the two classes of stimuli in the test situation. It was further suggested that non-contingently poisoned control groups should routinely be included in poison avoidance conditioning studies.  相似文献   
994.
Available evidence seems to indicate that illusion decrement represents reorganization of cognitive components involved in visual-geometric illusions. Observers viewed one of the two forms of the Mueller-Lyer illusion, containing differential opportunities for peripheral structural interactions, for a 10-min test session on each of 5 successive days. The magnitude of the distortion decreased to a different asymptotic level in each of the two configurations with the form, with more opportunity for structural interactions showing the higher asymptote. Thus, this asymptote probably represents the structural or physiological contribution to the illusory distortion.  相似文献   
995.
996.
Three experiments which tested the attention decrement explanation of the primacy effect in impression formation are reported. A memory-crowding interpretation of attention decrement would predict a decrease in primacy as the interval between traits is increased. Mild support was obtained in Experiment I but not in II or III. Overall. the magnitude of the primacy effect was independent of intertrait temporal variation. Decrement in attention is the most attractive theoretical explanation for the commonly obtained primacy effect. However, the results of the present series of studies suggest that this explanation is not tenable and that other theoretical mechanisms will be required to account for primacy effects.  相似文献   
997.
The block-design subtest of the WISC was presented in two forms, the standard red/white and an alternative blue/yellow, to two groups of fourth- and fifth-grade children. Twenty black children and 20 white children performed the red/white task with no significant differences between their scores. Another 20 black and 20 white children performed the blue/yellow task showing a significant interracial difference. Within the group of black children there was also a significant difference between the red/white design scores and the blue/yellow design scores. It is proposed that genetically determined differences in the pigmentation of the fundus oculi account for these results.  相似文献   
998.
The generalization of newly learned behaviors to different settings on the part of an autistic child and his parents was investigated by means of a multiple baseline design. Contingency management techniques were taught to the parents while they interacted with their child in a training apartment equipped with observation facilities. In order to assess whether the parents generalized the use of these techniques, data were gathered at their own home. Data were also gathered in the child's school in order to ascertain whether changes brought about in the child's behavior in the training apartment generalized to the school situation. It was concluded that the child's behavior was responsive to the contingencies of each particular environment. Generalization did not occur until the contingencies and stimulus cues were specifically designed to promote a change in behavior in each setting.  相似文献   
999.
We have used a null method to measure the orientation-contingent aftereffects of color first described by McCollough. After alternately inspecting, for example, a green horizontal line grating and a magenta vertical line grating, the Os report that in achromatic test gratings the horizontal lines appear pinkish and the vertical lines appear greenish. We have used a special color-mixing projector to add variable amounts of green and magenta light to the test gratings until they appear matched and nearly achromatic. The colorimetric purity needed to achieve this null setting is a quantitative measure of the strength of the colored aftereffect. Following inspections of the colored patterns ranging from 15 sec to 150 min, six Os showed aftereffects lasting from a few minutes to 7 or more days. The indices of colorimetric purity increase with inspection time and decline with time after inspection. The decay function is not quite linear either on semilog or on log-log coordinates. The rate of decay is mainly dependent on the magnitude of the effect built up during inspection. We conclude that the buildup and decay of these aftereffects show some of the time characteristics usually associated with central adaptability rather than sensory adaptation.  相似文献   
1000.
According to Sperling's (1967) model of short-term memory briefly presented masked stimuli are rapidly read into a non-visual Recognition Buffer (the RB model). An alternative interpretation of the data is that the stimulus information is coded into a non-iconic Visual Buffer where it is held while a much slower recognition process takes place (the VB model). The high frequency of errors in experiments with sequentially presented stimuli appears to refute the possibility that recognition is as rapid as suggested by the RB model. However these data may be attributed to variations in effective stimulus duration and stimulus quality rather than to slow recognition time. In an experiment to control for these effects, normal, laterally inverted and spaced digits were presented in a rapid sequence (1-10 items/s) with intervening pattern masks to keep the stimulus/mask interval constant. The recall data showed that order errors increased with rate of presentation but that item errors remained invariant. At the fastest rates of presentation there were fewer order errors for spaced than for coincident digits. It was argued that the results, as a whole, were more consistent with the VB than the RB model and that there is no evidence for identification times as fast as 10-40 ms/item.  相似文献   
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