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911.
Three-, four-, and five-year-old children's categorical and comparative understanding of high and low were examined in two experiments. Categorical knowledge was assessed by presenting subjects with a single object at varying heights (from 0 to five feet above the ground), and asking if the object was high or low. Comparative understanding of the terms was assessed by showing children two objects at a time and asking which was higher or lower. We observed two patterns of performance in children's categorical treatments: younger children in particular defined disjoint categories for high and low such that they only labelled the extreme heights as high or low, and maintained that middle heights were neither high nor low. Older children defined either-or categories such that all heights were labelled either high or low. We also found that children who defined either-or categories made correct comparative judgments across the entire range of variation whereas children who defined disjoint categories could only judge which of two objects was higher if the objects were not low (at 0 and 1 feet) and which of the objects was lower if the objects were not high (at 4 and 5 feet). The results were interpreted as reflecting a lack of appreciation that the terms are interdefined as negations of each other, and were discussed in terms of the similar semantic-congruity effects found in adults. 相似文献
912.
This study reports the case of a 42-year-old man who suffered a ruptured aneurysm of the anterior communicating artery. His memory capabilities were assessed after a considerable recovery period during which many of his memory deficits ameliorated. His scan revealed a left frontal lesion and many of his deficits were characteristic of frontal impairment. He was impaired on temporal discrimination, and he showed marked source forgetting. He also performed badly on the Brown-Peterson task, and we suggest that this is another task that may be characteristic of frontal impairment. In contrast, the patient showed normal or near normal performance on some memory tasks but not on others. It is concluded that the patient's frontal signs are similar to those found in Korsakoff's Syndrome, but that his memory impairment is qualitatively different from that encountered in patients with the amnesic syndrome. 相似文献
913.
914.
915.
This study examined differences in K-ABC performance between at-risk (n = 44) and normal (n = 49) preschool children. For the group at-risk, all of the mean global scores on the K-ABC clustered around a standard score of approximately 90. The normal group's mean scores were 15 to 21 standard-score points higher and clustered near 110. The results of t tests for independent samples indicated that the normal group's scores on both the global scales and K-ABC subtests were significantly higher than the at-risk group's scores in nearly every instance. Correlations among scores were consistent with previous findings for preschoolers on the K-ABC. For the normal group, correlations obtained among the global scales were nearly identical to those reported for the standardization sample. For the at-risk group, however, the correlation of .75 between Sequential processing and Achievement was higher than that (.58) between Simultaneous processing and Achievement. 相似文献
916.
917.
DOES CONTINGENT REINFORCEMENT STRENGTHEN OPERANT BEHAVIOR? 总被引:6,自引:5,他引:1
In Experiment 1, pigeons were trained to peck keys with equal food-reinforcement schedules in components that ended with either noncontingent or contingent transitions to a third component with a five-fold richer schedule. Response rates were higher in the initial component with contingent transitions, but resistance to prefeeding or extinction was not consistently greater. Experiment 2 also included noncontingent or contingent transitions to a signaled period of nonreinforcement. There was no effect of the contingency on transitions to nonreinforcement, but the difference in response rates maintained by contingent versus noncontingent transitions to the richer schedule was replicated. In addition, response rates were higher in components that preceded nonreinforcement than in components that preceded the richer schedule. However, resistance to extinction was greater for noncontingent transitions to the richer schedule than to nonreinforcement, implicating stimulus–reinforcer relations in the determination of resistance to change. Resistance to change was also somewhat greater for noncontingent than for contingent transitions to the richer schedule. The latter result, together with the results of Experiment 1 and related research, suggests that response-contingent reinforcement does not increase resistance to change. 相似文献
918.
R. B. Zajonc Pamela K. Adelmann Sheila T. Murphy Paula M. Niedenthal 《Motivation and emotion》1987,11(4):335-346
This study attempted to determine whether people who live with each other for a long period of time grow physically similar in their facial features. Photographs of couples when they were first married and 25 years later were judged for physical similarity and for the likelihood that they were married. The results showed that there is indeed an increase in apparent similarity after 25 years of cohabitation. Moreover, increase in resemblance was associated with greater reported marital happiness. Among the explanations of this phenomenon that were examined, one based on a theory of emotional efference emerged as promising. This theory proposes that emotional processes produce vascular changes that are, in part, regulated by facial musculature. The facial muscles are said to act as ligatures on veins and arteries, and they thereby are able to divert blood from, or direct blood to, the brain. An implication of the vascular theory of emotional efference is that habitual use of facial musculature may permanently affect the physical features of the face. The implication holds further that two people who live with each other for a longer period of time, by virtue of repeated empathic mimicry, would grow physically similar in their facial features. Kin resemblance, therefore, may not be simply a matter of common genes but also a matter of prolonged social contact.A. L.Dear A. L.: As far as physical appearance is concerned, likes seem to attract. Some experts feel that this resemblance may partly be explained by the fact that couples who've lived together for some time usually eat the same diet and share the same habits.
The Joyce Brothers Column
April 1985
This work was supported by Grant BNS-8505981 from the National Science Foundation. We wish to thank all those who offered their photographs for the purposes of this study, and Joseph R. Zajonc for his helpful suggestions. 相似文献
919.
920.
Stanton Newman Peter Smith Tom Treasure Philip Joseph Peter Ell Michael Harrison 《Current Psychology》1987,6(2):115-124
This study examines a series of coronary artery bypass patients (CABS) for neuropsychological and regional cerebral blood
flow (RCBF) changes at 8 days and 8 weeks post surgery. Seventy-three percent were found to have moderate or severe neuropsychological
deficits at 8 days post operation and 37% at 8 weeks post surgery. A comparison group of major vascular and thoracic surgery
patients was also found to have a significant proportion of neuropsychological deficit following surgery. The RCBF assessments
indicated a significant drop in mean RCBF at 8 days post surgery in the coronary artery bypass group which did not persist
to 8 weeks. The comparison group showed no changes in RCBF following surgery. The findings suggest different patterns of recovery
and origins of the neuropsychological deficit in the two groups and emphasize the need for appropriate control groups in studies
examining the cortical effects of extracorporeal circulation.
In addition, the project received generous support from the special trustees of the Middlesex Hospital. 相似文献