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71.
72.
Summary This article reports an experimental investigation testing the hypothesis that recall reports are systematically biased by the recaller's knowledge about who is to receive the recall report, while that bias is absent from a recognition test. Subjects listened to one of two versions of a story recounting John's visit to the doctor. After the story was read, subjects were asked to recall the story either with standard-recall instructions or with instructions to recall for peers, for Martians, or for a contest. In a fifth condition, subjects performed a filler activity, viz., the recall of a personal experience. After the recall test subjects were administered a recognition test. Between the groups no systematic differences in memory performance were observed in the recognition test. Recall for peers appeared to be poorer than recall in the other conditions. Subjects in the recall for a contest condition scored higher than the subjects in the other groups. Not only did groups differ with respect to bias, but there were also systematic differences in the memory or discrimination scores. The findings are discussed within the framework of schema theory.  相似文献   
73.
Summary The ability of aphasic patients to comprehend sentences involving the combination of two linguistic operations was tested in a sentence/picture matching task. Sentences included affirmative, negative, uncompared and comparative types. Aphasic patients had significantly greater difficulty in understanding negative-comparative constructions than sentence types involving only a single operation. Comparison of the responses of the aphasic patients with data obtained in a perceptual comparison task revealed that a subgroup of patients had marked difficulty in integrating information in both tasks. The results are interpreted as an indication that some aphasic patients are especially disturbed in their ability to combine several operations in the construction of semantic representations for sentences. It is further argued that this deficit may extend to an inability to integrate information in the perceptual/spatial domain, as suggested by Luria in his discussion of the syndrome of semantic aphasia.The research reported here was supported by NIH research grant 14099 to The Johns Hopkins University. We would like to thank Dr. Annamaria Basili, Chief, Department of Audiology and Speech Pathology, Fort Howard Veterans Administration Medical Center, for permission to test the patients. We are indebted to the entire staff of that department for their continued cooperation, and for their many useful comments on the research reported. We also thank Michael Giordano, Conrad Selnick, and Susan Baisley for their assistance in data analysis. A version of this paper was presented at the annual meeting of B.A.B.B.L.E., Niagara Falls, Canada, March, 1979  相似文献   
74.
75.
Neurogenesis continues to occur throughout life in the dentate gyrus of the hippocampus and may be related to hippocampus-dependent learning. We have recently reported that there is an enhancement of neurogenesis in the hippocampus only when BrdU is administered 6 days prior to starting spatial training but not when training started either 1 day or 11 days following BrdU administration. In that study, all rats were perfused on day 16 after BrdU injection in order to compare cells of the same age (i.e. 16 day old cells) and thus the survival time after learning was different between groups. This study was designed to address whether the amount of time that passed following training could also contribute to the effects of spatial learning on hippocampal neurogenesis and whether there was differential new neuron activation in response to spatial learning that depended on the age of new cells at the time of spatial learning. Here we tested whether a survival period of 5 days following spatial learning at either 1-5, 6-10 or 11-15 days following BrdU administration would alter cell survival and/or activation of new neurons. Our results indicate that 5 days after training in the Morris water task cell survival is unaltered by training on days 1-5, increased by training at days 6-10 and decreased when training occurs on days 11-15. Furthermore spatial learners trained on days 6-10 or 11-15 show greater activation of new neurons compared to cue-trained rats during a probe trial 5 days after training. In addition, rats trained on the spatial task on days 11-15 had a greater number of activated new neurons compared to rats trained on the spatial task on days 6-10. These results suggest there is a gradual removal of older BrdU-labeled new neurons following spatial learning perhaps due to a competitive interaction with a population of younger BrdU-labeled new neurons.  相似文献   
76.
This article studies convergence across Italian regions by means of two composite indicators of socio-economic progress reflecting the multidimensional nature of human well-being. The first composite indicator includes, other than household disposable income in Italy, two sub-indicators regarding health and education; the second composite indicator considers, in addition to those considered by the former, three further sub-indicators relating to the quality of the socio-institutional context, age and gender disparities in the labor market and regional competitiveness. The data base of the 17 variables or indexes used to construct the six abovementioned sub-indicators cover the period from 1998 to 2008. We assess the existence of both σ and γ- convergence; the latter computed by means of Kendall′s index. Consistent with the findings in other European countries that also use composite economic and quality of life indicators we find evidence of regional σ-convergence in well-being, but do not observe significant processes of intra-distributional mobility. In other words, while dispersion across Italian regions in terms of well-being levels declined in the period, the regional ranking remained substantially unchanged.  相似文献   
77.
The influence of estradiol on learning and memory is dependent on a number of factors. The effects of physiological levels of estradiol on the acquisition of a spatial working memory task mediated by the prefrontal cortex (PFC) and the hippocampus were examined in Experiment 1. Ovariectomized Long-Evans rats received daily injections of estradiol or vehicle were tested on the win-shift version of the radial arm maze. A high dose of estradiol benzoate (5 microg) enhanced acquisition of the task, whereas a low dose of estradiol (0.3 microg) increased the number of errors committed over 17 days of testing. Experiment 2 was conducted to examine site-specific influences of estradiol on spatial working memory in well-trained rats. Saline and estradiol cyclodextrin (0.1 and 0.9 microg) were infused into the prelimbic region of the PFC or dorsal hippocampus 40 min prior to testing on the win-shift task. Infusions of estradiol into both brain areas attenuated saline-infusion disruptions in working memory. Specifically, the higher dose of estradiol facilitated working memory when infused into the PFC, whereas the lower dose of estradiol facilitated performance when infused into the dorsal hippocampus. Moreover, working memory was significantly impaired 24 h after infusions of estradiol into the dorsal hippocampus but not the PFC. These data provide further evidence for the notion that estradiol can dose-dependently alter memory processes and suggest that facilitation or disruptions of working memory by estradiol are site- and time-specific.  相似文献   
78.
The present study provides a preliminary validation of the Lithuanian version of the Strategy and Attribution Questionnaire (SAQ, Nurmi, et al., 1995), a self-reported measure of social and cognitive behavioral strategies. An attempt to validate SAQ subscales was made by correlating them with the Youth Self-Report (Achenbach, 1991) and school grades. This was done with a sample of 14- to 17-year-old adolescents (N= 734). The results showed that although internal consistency reliabilities were good, they were lower when compared with the original version of SAQ. The SAQ subscales were moderately associated with various validity criteria, such as anxiety/depression, withdrawal, social problems and somatic complaints and school grades. Results also showed moderate correlations between similar strategic components across achievement and affiliative situations. The results provide preliminary evidence for concurrent validity of the Lithuanian version of SAQ.  相似文献   
79.
The Ten-point Clock Test can be used to identify early forms of Alzheimer's disease because it is reliable, well accepted, and easily administered at the bedside. Nevertheless, its clinical role in the detection of early dementia and its correlations with other cognitive processes is still under investigation. Vascular dementia is an uncertain nosological entity, in which unevenly distributed patterns of cognitive deficits comprising slowing of cognitive processing and impairment of executive function occur. The present study assessed how the Clock Test scores correlated with a number of other neuropsychological and functional tests in a sample of 144 patients with vascular dementia, who were followed for a period of 24 mo. At baseline, at 12 mo. and at 24 mo. subjects were administered a battery of tests, including the Mini-Mental State Examination, word fluency, visuospatial skills, an evaluation of hetero- and autotopognosia (knowledge of self), the Proverbs Test, and the Ten-point Clock Test. For these patients scores on the Clock Test correlated significantly with semantic abilities, with abstract reasoning capacities, visuospatial perception, and with right and left recognition.  相似文献   
80.
Evidence on the relationship between income inequality and suicide is inconsistent. Data from the New York City Office of the Chief Medical Examiner for all fatal injuries was collected to conduct a multilevel case-control study. In multilevel models, suicide decedents (n=374) were more likely than accident controls (n=453) to reside in neighborhoods with greater income inequality even after controlling for individual characteristics; this relation was modified by age with an effect overall and among decedents aged 15-34 but not among decedents 35-64. These data suggest that income inequality may contribute to the risk of suicide in younger adults.  相似文献   
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