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931.
Past studies have shown that disruptive behavior can be eliminated and attending behavior accelerated in an academic setting. The relationship between these behaviors and academic performance is not well understood. The effects of behavioral and performance contingencies on classroom behavior and on academic performance were investigated. The subjects, third-grade students from an inner city elementary school, were exposed to a series of conditions including baseline, behavior contingencies, performance contingencies, and a mix of behavior and performance contingencies using a reversal design. The students worked 100 randomly selected mathematics problems for 20 minutes each day during each period. Behavioral contingencies improved attending and decreased disruptions but did not improve performance. Performance contingencies increased per cent correct problems but attending declined and disruptions increased. The combined contingencies increased both performance and attending. The experiment was replicated with another class of children varying the sequence of conditions and the amount of token reinforcement that could be earned. The findings emphasized the importance of designing specific contingencies for specific target behaviors. Behavioral contingencies did not have the positive effect on performance often implied, nor were performance contingencies alone able to maintain acceptable classroom behavior.  相似文献   
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Adaptation to spectacles that alter in equivalent amounts the accommodation and the convergence with which objects are viewed was produced under two conditions. In one, S alternately pushed away or pulled toward him a screen that exhibited only a single vertical contour while wearing glaaaes that caused decreases in accommodation and convergence equivalent to 1.5 lens diopters. Here kinesthesis for these arm movements provided the only veridical distance cues, A small, but highly significant, adaptation effect was obtained with a teat in which S, before and after the adaptation period, pointed to the location of a test line in the distance dimension. Corresponding tests consisting in size and in depth estimates did not show an adaptation effect. In the other condition of adaptation, S moved objects by hand toward and away from himself while wearing spectacles that increased accommodation and convergence by the equivalent of 1.5 lens diopters. In addition to the altered oculomotor cues, some veridical visual cues for distance such as are caused by perspective were present. This condition yielded changes in size and depth estimates indicative of an adaptation in visual distance perception and a larger effect of adaptation measured by the pointing test. We concluded that the excess of the adaptation effect measured by pointing over that measured by size estimation represents an adaptation in proprioception, as did the pointing effect produced by our first adaptation condition.  相似文献   
935.
In five experiments, Sa were presented with a variety of sour and bitter compounds after the tongue was rinsed with distilled H20, QHCl, urea, or citric acid. All the acids tested were significantly less sour following adaptation to citric acid than after adaptation to distilled H2O. The taste of these acids was not affected by rinsing the tongue with QHCl or urea. QHCl adaptation markedly reduced the bitterness of some compounds, while having little effect on others, including urea and citric acid. Both urea and citric acid had smaller but reliable effects on the bitterness of QHCI. These apparently incompatible results do not seem to be the result of a simple verbal confusion between sourness and bitterness. Some compounds were not affected by any of the adapting conditions. The coding mechanisms for the sourness of acids appears to be relatively simple, while that for bitterness is more complex.  相似文献   
936.
Rats were trained in a six-choice jumping stand apparatus to enter the dark door, and avoid the five bright doors. Rats with bilateral superior collicular lesions were found to be severely impaired in this task, although further experiments showed that they were able to discriminate bright from dark stimuli and could perform correctly if allowed to approach each door in turn. It is suggested that the superior colliculus is important in orientation to visual cues, and there is some evidence that it is involved in orientation to brightness but not visual form cues.  相似文献   
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In two separate studies underclassmen on academic probation (N = 27, N = 22) were individually matched for aptitude with academically satisfactory students to investigate (a) nonaptitudinal factors differentiating probation students from matched students and (b) how probation students who eventually have to withdraw differ from those who improve. Results based on interviews, questionnaires, and self-report measures indicate that probation students have unrealistically optimistic expectations concerning grades, attribute their difficulties to academic factors rather than personal concerns, and tend to be defensive, lacking in positive motivation for academic work, and relatively dependent on their parents. Students most likely to get off probation estimated their grades most accurately and had lowest test anxiety  相似文献   
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