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991.
Two versions of a distributed-memory model, one for associative information and one for serial-order information, leave open the question of whether there are two different modes of operation or only one. An analysis of these two versions showed that differential predictions emerge when one considers the role of item information. To test these predictions, a standard item-recognition task (Sternberg, 1966) was embedded in a paired-associate probe-recognition task, a serial-order probe-recognition task, or both. The item-recognition serial-position curves were quite different in the paired-associate and the serial-order conditions, and followed the paired-associate condition when the two were combined. In general, the results were consistent with the predictions of the distributed-memory models, and supported the idea of different modes of operation rather than a single common mode of operation.  相似文献   
992.
993.
The performance of poor and normal sixth-grade readers was compared on an auditory short-term memory task in two studies. In the first study, the effects of distraction, list length, and speed of stimulus presentation were investigated to test the hypothesis that the performance of the poor readers is affected by deficits in selective attention. Group differences in performance, however, were obtained for both distraction and no-distraction conditions. The second experiment examined the hypothesis that group differences may reflect differences in the use of rehearsal. In the second experiment, half the reading-disabled children and half the controls were provided with rehearsal training prior to completing the same short-term memory task a second time. Rehearsal training resulted in improved performance relative to children who were not trained; however, there was no rehearsal training x reading group interaction. The poor readers continued to show deficits in performance relative to the performance of control children. The results of these two studies suggest that deficits observed for poor readers on short-term memory tasks may reflect processing difficulties in some area that precedes rehearsal and affects performance under both distraction and no-distraction conditions.The authors wish to express their thanks to the Sachem School District and Betty Gould, Nicholas Opinanate, and Guy Barber for their unlimited cooperation, and to John Neale for very helpful discussions of a number of issues in this paper.  相似文献   
994.
The Family Adaptability and Cohesion Evaluation Scales (FACES), a measure of family functioning, contains three scales: cohesion, adaptability, and social desirability. These were slightly modified (FACES- R) on the basis of pilot data and were administered to 42 clinic families (families seeking or receiving psychological services) and 206 nonclinic families. Support for the scales was found in high coefficient alpha reliabilities and similarity of the sample means and standard deviations to those of the standardization sample. However, there was little agreement among family members' scale scores. Therapists' ratings of cohesion and adaptability did not correlate with scale scores among clinic families. There was no difference between clinic and nonclinic samples on the cohesion or adaptability scales, although the social desirability scale did discriminate between groups. Factor analysis suggested that cohesion, adaptability, and social desirability cannot be clearly differentiated using this measure.This work was supported by the American Association of University Women and by Grant R01HD13820 from the National Institute of Child Health and Human Development.  相似文献   
995.
The relationship of self-concept (self-esteem and mastery) and social support to psychological distress was studied among 68 Israeli women immediately prior to undergoing biopsy for suspected cancer (acute stress) and 3 months later for the noncancer group (everyday stress). It was predicted that women with stronger self-concepts and more social support would experience less state depression and state anxiety during the acute crisis than women with weaker self-concepts and less social support. It was further predicted that self-concept would be more critical than social support due to the acute nature of the event. Finally, self-concept was predicted to be related to psychological distress both during the acute and everyday stress situations (a direct effect), while social support was predicted to be related to psychological distress only during the acute stress situation (a buffering effect). The hypotheses were generally confirmed. However, self-concept and social support were seen as complexly related to psychological distress during the acute phase, one not necessarily being more critical than the other. The selective employment of available resistance resources to fit the situation and implications for preventive intervention were discussed.  相似文献   
996.
997.
998.
Periadolescent rats exhibit a number of behavioral differences in comparison with younger or older animals. For instance, periadolescents tend to show enhanced acquisition of simple active avoidance tasks, but impaired acquisition of more complex appetitive and aversive discriminations. In this experiment, rats were trained on a simple passive avoidance task at one of three ages, as weanlings (25 days), periadolescents (35 days), or young adults (45 days). Training occurred in the presence of both a redundant discriminative stimulus and a specified, redundant contextual stimulus. The periadolescents did not differ from either younger or older rats in rate of learning the passive avoidance task. The retention performance of these animals was then tested following a change in either, neither, or both of the redundant cues. When a measure of performance that controls for baseline activity was used, it was observed that periadolescents were not disrupted by a change in the redundant discriminative stimulus, a cue change that clearly disrupted performance in 25- and 45-day-old animals, and tended to be more disrupted by the contextual change than younger or older rats. It is hypothesized that the alterations in performance exhibited by periadolescents may be related to an ontogenetic alteration in stimulus selection modulated by the catecholaminergic systems.  相似文献   
999.
The effect of environmental enrichment on normal rats, rats that received hemidecortication at birth, and rats that received hemidecortication when adult was studied in the Morris water task, which is a spatial navigation task requiring the use of distal cues for successful performance. Enrichment was achieved by housing the rats for 90 days in a large outdoor compound that was designed to model a natural environment. Adult hemidecorticated lab-raised rats were severely impaired in the acquisition of the task but neonatally hemidecorticated rats, although also impaired, showed significant sparing. Postsurgical, but not presurgical, enrichment of adult hemidecorticated rats significantly enhanced their recovery. Enrichment had little effect on neonatally decorticated rats or on normal rats. Although there were no gross anatomical changes associated with enrichment, the paradigm provides both a robust phenomena and a cortically dependent task that is ideal for investigating the processes in the remaining intact hemisphere that must support recovery.  相似文献   
1000.
A total of 1505 children (633 boys and 872 girls) completed the I6 Impulsiveness Questionnaire. Reliabilities, scale intercorrelations and means and standard deviations are given after slight modifications were made to the original scoring key on the basis of factor analyses. Age means for both sexes are also given.  相似文献   
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