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81.
Neuronal changes in normal human aging and Alzheimer's disease   总被引:8,自引:0,他引:8  
This article discusses age-related changes in brain weight, total number of cortical neurons, cortical dendrites, spine, and synapse density. The conclusion is that the present outlook is less grim than it was 30 years ago. Age-related reduction appears to be specific to brain region and cortical layer rather than a general feature. In addition, we describe a different pattern of changes that occur in Alzheimer's disease patients. This review concludes that the association cortices in particular are affected in aging and Alzheimer's disease and that the primary visual and somatosensory cortices are relatively spared.  相似文献   
82.
We examine the hypothesis that the efficiency of executive control processes is less stable over time in older than younger adults. An age-related decrease in the efficiency of executive control should result in an increase in performance variability in task conditions requiring the recruitment of executive control processes and not in task conditions requiring minimal involvement of executive control. Performance variability was similar for younger and older adults in task conditions requiring minimal executive control and greater for older than younger adults in task conditions requiring executive control. These and other data are consistent with the proposal that aging is associated with a decrease in the stability of executive control over time.  相似文献   
83.
Rejuvenescence has long been a topic of legend and medicine. As the body became the property of medical science, speculative fiction asked how fantastic experiments with bodies would affect the life course. In science fiction, medical breakthroughs promise or threaten to forestall or even reverse the decline from midlife through old age to senility and decrepitude. Responding to debates over evolution, eugenics, and scientific experimentation with human and animal subjects, rejuvenescence novels such as Bruce Sterling's Holy Fire (1996) ask readers whether they desire long life or heightened quality of life; the consolations of age or the hungers of youth; short-lived intensity or perpetual ennui.  相似文献   
84.
The interconnection of social theory to social aspects of aging has grown in recent years. The theoretical movement entitled structured dependency, couched in social class analysis, has tended to ignore an understanding of aging identity, the body, cultural representations of aging, and positive images of aging, all of which are central features of an emerging postmodern paradigm in gerontological theory. This article argues that the concept of gender can form a useful bridge, a continuity, between structured dependency and postmodernism in theoretical gerontology. Unfortunately, the compartmentalization of these two conceptual approaches has made their links difficult to forge. This article attempts to take a first step in this direction by highlighting the way postmodern ideas can be used to understand a modernist issue—gender in a gerontological context. Also, focusing on the aging body as a primary form of analysis generates some novel insights into the importance of both the theoretical understanding and cultural representations of the body.  相似文献   
85.
The film She's Been Away tells the story of an old woman who had been locked in a mental asylum while a teenager, for willfully violating repressive sexual codes. Sixty years later her ward is closed and she moves in with her nephew and his wife. Faced with what appears to be a hopeless situation, she manages to forge a sense of a meaningful closure to a misspent life. Through narrative, story structure, and characterization the film throws into focus coping mechanisms and ego strategies deployed by a triple disadvantaged person (woman, old, and mad) in her ascent to a reconstructed selfhood. As the protagonist ties both ends of her life, and faces the abyss in between she makes genuine adaptive use of so-called regressive, late-life development assets (available to a lesser degree to elderly people in normal life circumstances), primarily the abolition of linear time. Through this abolition she makes reminiscing an actual reality while still maintaining a functional separation between the real and the remembered. Her portrayal is a valuable document for gerontologists as it explores, through artistic imagination and intuition, the workings of an aging mind in search for a meaningful sense of closure.  相似文献   
86.
By applying results from in-depth interviews with older Iranian Sufis residing in Sweden, this article describes the benefits of the value system of Sufism prizing mystical union above self-realization. As persons conceive of themselves as all forming parts of other-than-self rather than as separate selves, the result is tolerance towards other people's opinions and the vanishing of hostile feelings and competition. Compassion and identification with the whole of creation allows Sufis to avoid the sense of loneliness and exclusion felt by so many immigrants.  相似文献   
87.
An age-related decline in memory has been reported in male rats; however, there are few studies that have addressed these changes in aged female rats. In young female rats, hormonal cycles influence behavior. By the age of 22 months most female rats have not had regular hormonal cycles for at least 9 months. In the current study we examined how the hormonal status (persistent estrus and pseudo-pregnant) of the aged (22-24 months) female rat (Long Evans) influenced performance on a spatial version of the Morris water maze and compared this to aged male rats. Aged females in persistent estrus showed better performance on the water maze than both aged females that were pseudopregnant and aged males. Thus, postestropausal hormonal status may influence the course of aging in females.  相似文献   
88.
中小学生认知能力发展水平测验的研究   总被引:4,自引:0,他引:4  
以皮亚杰的认知发展理论为基础,采用皮亚杰及其学生研究认知发展时的任务为测验题目,编制成测量中小学生认知能力发展水平的测验.通过对2240名中小学生施测,结果表明本测验不仅具有很好的信度和效度,而且也具有适中的难度.然后以一所中学特长班学生为被试,通过对他们进行测量,并将测验结果与同年级普通班学生的认知成绩进行比较,结果存在很明显的差异.最后对中小学生认知能力发展水平测量问题进行了探讨.  相似文献   
89.
Needham A  Dueker G  Lockhead G 《Cognition》2005,94(3):215-240
Four- and-a-half-month-old infants' (N = 100) category formation and use was studied in a series of five experiments. For each experiment, the test events featured a display composed of a cylinder and a box. Previous research showed that this display is not clearly parsed as a single unit or as two separate units by infants of this age. Immediately prior to testing, infants were shown a set of category exemplars. Knowledge about this category could help infants disambiguate the test display, which contained a novel exemplar of this category. Clear interpretation of the test display as composed of two separate units (as indicated by infants' longer looking at the move-together than at the move-apart test event) was taken as evidence of category formation and use. In Experiments 1 and 5, infants' prior experience with a set of three different boxes that were similar to the test box facilitated their segregation of the test display. Experiment 2 showed that three different exemplars are necessary: prior experience with any two of the three boxes used in Experiment 1 did not facilitate infants' segregation of the test display. Experiment 3 showed that variability in the exemplar set is necessary: prior experience with three identical boxes did not facilitate infants' segregation of the test display. Experiment 4 showed that under these conditions of very brief prior exposure, similarity between the exemplar set and test box is necessary: prior experience with three different boxes that were not very similar to the test box did not facilitate infants' segregation of the test display. Together, these findings suggest that: (a) number of exemplars, variability, and similarity in the exemplar set are important for infants' category formation, and (b) infants use their category knowledge to determine the boundaries of the objects in a display.  相似文献   
90.
There is a wealth of data indicating the effectiveness of cognitive behavioral therapy in the treatment of bulimia nervosa. However, the best evidence indicates a treatment success rate of 50%. The purpose of this paper is to briefly describe cognitive behavioral treatment of bulimia nervosa and to offer suggestions on how this therapy approach may be tailored to best serve the needs of individual clients. Such tailoring should ultimately lead to even greater treatment success.  相似文献   
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