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51.
Aged rats with extensive prior training on the radial maze retain the capacity for accurate spatial working memory (WM) for at least 3 months without practice. To investigate the temporal limits of this influence of prior experience we compared the reacquisition of spatial WM by a group of experienced 21.5-month-old rats to the original acquisition by naive 3-month-old rats. The aged rats had received 225 radial maze tests between 3 and 11 months of age. Despite 10 months without practice the old rats rapidly reacquired critical performance. Their reacquisition was markedly superior to original learning by the young rats, even when delays as long as 5 h were imposed between the rats' fourth and fifth choices during the daily tests in the eight-arm maze. Additional tests showed that neither young nor old rats employed a response strategy to maintain accurate spatial WM performance. Experience clearly confers long-lived protection against the otherwise deleterious effects of aging on spatial WM, but the mechanism by which this influence arises is unknown. 相似文献
52.
Cue depreciation: when word fragment completion is undermined by prior exposure to lesser fragments 总被引:3,自引:0,他引:3
Z F Peynircio?lu M J Watkins 《Journal of experimental psychology. Learning, memory, and cognition》1986,12(3):426-431
The ability to think of a previously studied item has often been shown to be impaired when, in one way or another, the extraitem context is changed from study to test. In a series of five experiments, such impairment is induced in a somewhat different way. A fragment (e.g. r-i--rop) of a just-studied word (raindrop) is shown to be less readily completed if it is presented bit by bit (r------p, r----r-p, r-i--r-p, r-i--rop) rather than all at once (Experiments 1, 3, 4, and 5). No such effect is found if the word has not been studied beforehand (Experiments 2, 3, 4, and 5). This pattern of results occurs even when fragments of studied and nonstudied words occur in the same test and under conditions in which subjects cannot tell whether a given fragment is of a studied or nonstudied word (Experiments 4 and 5). In addition, for words that have been studied beforehand, the impairment is shown to increase systematically with the number of steps involved in the presentation of the word fragment (Experiment 3) and also to persist when the time allowed for completion of the final version of the fragment is increased from 4 s to a full minute (Experiment 5). 相似文献
53.
继《再认性同一判断中汉字信息的提取》一文之后,我们作了《回忆性同一判断中汉字信息的提取》的研究,进一步研究了在同一性判断中汉字信息的提取问题,旨在比较在回忆与再认条件下人们对汉字信息提取的特点。结果表明,在回忆条件下意同判断的反应时最长,音近其次,形似最短。形似与意同判断,音近与意同判断间反应时差异显著,音近与形似之间不显著。 与前次实验相比。在回忆条件下语音的作用提高了,但形的作用仍然很大,说明字形与字音的编码对提取语义信息都有重要作用。同时,在回忆条件下,特征干扰都大于一般分心物的作用,说明单词的各种特征都影响到汉字信息的提取。 相似文献
54.
速示下再认汉字的某些特征 总被引:5,自引:1,他引:4
成人和小学生在速示条件下再认汉字和双字词,结果表明,成人和小学生再认不同结构类型的汉字有共同的规律:结构上属于两边对称的字较易再认,半包围型的字较难再认。成人和小学生在再认过程中抽取汉字的特征也有共同之点:对左右结构型的字往往抽取字的右下角的笔划,对半包围型的字则往往抽取字的左上角的笔划。不同再认的方式(读出和指认)对再认的成绩有明显的差别。在指认条件下由于有视觉反馈,再认成绩大为提高。本实验的结果对识字教学和机器自动识到汉字装置的设计,可能有某些参考意义。 相似文献
55.
不同时相日光下颜色的恒常性 总被引:1,自引:0,他引:1
一、前言 在光源光谱成份改变的条件下,我们周围物体的颜色在眼睛看来保持相对不变,称为颜色恒常性。1807年Thomas Young首先描述了颜色恒常性现象,他指出室内不管是由蜡烛的黄光或火焰的红光来照明的,书页纸仍然看来是白色的。Young认为,外界某一表面的颜色外观,并不完全决定于网膜的红、绿、蓝三种感受器的吸收特性,而也依赖于周围其它物体射入眼睛的光通量。此后,E.Hering对颜色恒常性做了实验表演。一般认为颜色恒常性是对环境照明感受性的降低。视觉通道只传递由物体表面所反射的光谱成 相似文献
56.
57.
本实验采用四种不同显色特性的光源分别作为两种类型视标的照明。在同一照度上对各照明条件下的视觉敏度予以测定和计算。结果表明:增加光源显色指数对于颜色背景上黑色视标的辨认能力有所提高;而对于中灰色背景上颜色视标的辨认能力则有所下降。这种效果主要是由于在不同光源照明下,视标与背景的亮度对比变化所致。结果还表明:使用中灰背景颜色视标在辨认效果上优于颜色背景黑视标。对前一类型视标采用高压钠灯照明有助于提高视觉辨别力。这对推广应用这种显色指数较低,但光效率较高的新光源有实际意义。 相似文献
58.
E Müller A Schapowahl A Seel?nder 《Psychiatrie, Neurologie, und medizinische Psychologie》1984,36(8):480-488
The somatic and psychosocial development of 80 subjects with manifest affective-phasic psychoses is studied retrospectively and compared with that of an identically sized control group consisting of neuropsychiatrically healthy subjects. Statistically significant differences were found particularly in the answers to questions dealing with social situation and social adaptability. Achievement at school and vocational qualifications were lower among the parents of the patients than among those of the healthy subjects. Characteristic features of the patients' childhood and adolescence were transient depression, often for no apparent cause, and maladaption, and vocational wishes were fulfilled less often than among the controls. The patients experienced greater difficulty in settling in to a new group due to their contact difficulties. 相似文献
59.
T Krause W P Pankau A Wagner J L?ssner 《Psychiatrie, Neurologie, und medizinische Psychologie》1984,36(9):545-550
By 48 patients with Wilson's disease the brainstem acoustic evoked potentials were stated. There were 35 pathological findings (73%), 13 were normal (27%). The waves, determined by the middle and upper brainstem (Pons and Mesencephalon) showed most of all pathological changes. Those patients with forms of Wilson's disease called Pseudoskelerose and Pseudoparkinson showed the most pathological findings. But one could watch these findings by about 30% of patients in preclinical stage. This method can possibly be used for early detection of disorders of brainstem functions and in the same way it can be used for control of treatment by patients in preclinical stage. 相似文献
60.
Research has demonstrated that on the path from a creative idea to a creative outcome, high creativity motivation and self-efficacy do not necessarily lead to creative behavior. The present study proposed and examined the notion that daily creativity planning could promote creative behavior and contribute to the cultivation of creativity. A total of 77 middle school students (39 students in the experimental group and 38 in the control group) participated in this study, for which a quasi-experimental design was administered. The experimental group conducted a two-week daily planning for creative activities, while the control group did not conduct any intervention. The results showed that students' creativity motivation and creative self-efficacy were at relatively high levels overall and were positively and moderately correlated with creative behavior. Daily planning could effectively facilitate students' creative behavior. These findings point to a promising and simple creativity enhancement strategy for cultivating students to develop the habit of making creative plans in their daily lives. 相似文献