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31.
How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
32.
教育因素对认知功能年老化过程的影响   总被引:11,自引:3,他引:8  
应用言语-操作和人机对话两种方式共12项作业,完成年龄和教育因素对认知功能影响的研究,被试共734人,46-75岁.结果表明:(1)年龄和教育因素对认知成绩的影响因作业而异,分别为年龄影响明显(图象自由回忆和无意义图形再认)、教育因素影响明显(卡片分类、图象分类和矩阵填图)、年龄和教育因素影响均明显(符号数字、词对联想学习、听觉和视觉数字广度)或均不明显(心算).(2)四项非词语性作业速度明显受年龄和教育因素的双重影响.  相似文献   
33.
Investigated ethnicity and parental alcoholism as factors that might influence the stress vulnerability of adolescents. It extended an initial cross-sectional study of this same sample by adding two annual assessments which allowed for additional cross-sectional analyses and longitudinal tests. Hispanic and Caucasian adolescents (N=306 at Time 1) completed measures of their own life stress, family conflict, and alcohol use. Their parents reported on adolescents' internalizing and externalizing symptoms. Cross-sectional analyses at Time 2, and prospective analyses involving Time 1 and Time 2 measures were, for the most part, consistent with the original study's results. Caucasian adolescents and children of alcoholic parents appeared to be more vulnerable to stress than Hispanic adolescents and children of nonalcoholic parents. Family conflict was a partial explanation for this increased vulnerability. This research was supported by National Institute on Drug Abuse Grant DA05227 to Laurie Chassin (pricipal investigator) and Manuel Barrera, Jr. (coprincipal investigator). Susan Li was supported by an American Psychological Association Minority Fellowship Award. Portions of this research were presented at the conference, “Resiliency in Families: Racial and Ethnic Minority Families in America” that was held at the University of Wisconsin, May 31–June 2, 1994.  相似文献   
34.
临床经验对诊断的双重作用及改造   总被引:1,自引:0,他引:1  
文中用辩证唯物主义的观点,阐述了临床经验的定义、来源及指导实践过程中的意义,指出其具有促进诊断和引起误诊的双重作用,并用临床病历例子详细说明其双重作用的形式、导致结果及产生的原因。指出临床经验的双重作用在临床工作中的重要性及局限性,提出对经验的改造完善途径,以能充分表现出其促进诊断的作用,而最大限度降低其导致误诊的程度,发挥在临床工作中的良性作用。  相似文献   
35.
Li FP 《Ethics & behavior》1995,5(2):193-196
Case vignette: sharing unanticipated genetic information. The Questor family has experienced an unusual number of malignancies in the past two generations and has been advised by an oncologist that the p53 oncogene known as Li-Fraumeni Syndrome may be present in the family genome. The option of predictive genetic testing has been raised and several branches of the family have chosen to undergo screening to determine whether they are at risk for cancer because of the gene. Roger and Liz Questor have arranged for screening of themselves and their three children, ages 12, 10, and 7. The couple has, by all appearances, been happily married for 14 years. None of the family members are found to carry the oncogene; however, the geneticist conducting the analyses has made an interesting incidental discovery. The 10-year-old child is not the biological progeny of Roger Questor. Although the 12- and 7-year-olds are clearly the biological children of the couple, it is evident that the 10-year-old born to Liz Questor was fathered by a person other than Roger. What are the ethical obligations of the geneticist with respect to any sharing or disclosure of the information that has been discovered incidentally? What course of action, if any, do you recommend?  相似文献   
36.
合作学习对小学生同伴关系、成就动机和成就影响的研究   总被引:12,自引:0,他引:12  
旨在探讨在我国开展合作学习教学的可行性,以及合作学习对小学生同伴关系、成就动机和成就水平的影响,运用自然实验和测量相结合的方法,选择了北京师范大学实验小学三年级两个班进行实验研究,其中一个班为实验班(n=35),另一个班为控制班(n=37).实验为期三个月。结果表明:合作学习在小学教学中不但是可行的,而且效果较为显著;合作学习对同伴关系的改善有着积极的影响,学生间的接纳度和被接纳度都有普遍的提高;合作学习在较大程度上激发了学生的成就动机水平,学生对合作学习的课程兴趣明显提高.成绩较差的学生表现得更为明显;合作学习对提高学生的学习成绩有一定的促进作用。  相似文献   
37.
The visual field exerts powerful effects on egocentric spatial localization along both horizontal and vertical dimensions. Thus, (1) prism-produced visual pitch and visual slant generate similar mislocalizations of visually perceived eye level (VPEL) and visually perceived straight ahead (VPSA) and (2) in darkness curare-produced extraocular muscle paresis under eccentric gaze generates similar mislocalizations in VPEL and VPSA that are essentially eliminated by introducing a normal visual field. In the present experiments, however, a search for influences of real visual slant on VPSA to correspond to the influences of visual pitch on VPEL failed to find one. Although the elevation corresponding to VPEL changes linearly with the pitch of a visual field consisting of two isolated 66.5°-long pitched-from-vertical lines, the corresponding manipulation of change in the slant of either a horizontal two-line or a horizontal four-line visual field on VPSA did not occur. The average slope of the VPEL-versus-pitch function across 5 subjects was +0.40 over a ±30° pitch range, but was indistinguishable from 0.00 for the VPSA-versus-slant function over a ±30° slant range. Possible contributions to the difference between susceptibility of VPEL and VPSA to visual influence from extraretinal eye position information, gravity, and several retinal gradients are discussed.  相似文献   
38.
与年龄相关的认知速度减慢及学习改善过程   总被引:3,自引:0,他引:3  
该工作应用人机对话方式完成心算、符号数字、数字鉴别和计数四项作业认知速度年老减慢及学习改善过程的研究,被试350人,46—75岁。研究结果表明:四项认知作业速度随年老进行性减慢;然而,老年人经学习训练认知作业速度可明显改善。上述变化程度与作业所需时间有密切关系,提示年老过程中枢信息加工过程速度的减慢快于外周感觉─运动过程速度的减慢,学习改善作用也可能主要是中枢过程速度的提高。  相似文献   
39.
成人脑涨落图年龄变化特点的研究   总被引:13,自引:0,他引:13  
刘昌  李德明  梅磊 《心理学报》1996,29(3):307-314
该工作研究了120名20-79岁正常成人脑涨落图的年龄变化特点。结果表明:(1)从20岁到50岁,S系谱线活动向低频方向集中,60岁后谱线又向高频方向有所移动;(2)部分谐振系的随龄变化表现明显,其中以S17系变化最为敏感;(3)脑区间相干活动和各脑区的连频活动随年龄增强,脑能量分布的有序性逐渐破坏;(4)增龄性变化主要反映在优势脑区(左前脑)和优势脑轴(左前/右后脑)上,与脑高级机能活动密切相关的左前脑的退行性变化最为明显。上述结果反映了脑功能的减退是一个非线性的多层次的复杂过程。  相似文献   
40.
时序信息提取机制的探索   总被引:1,自引:1,他引:0  
李宏翰  黄希庭 《心理学报》1996,29(2):180-191
对时序信息加工的经典研究是采用新近性判断范型,结果发现其提取机制是以新近性为基础的逆向串行搜索过程。本研究采用新近性判断范型和早远性判断范型对时序信息的提取机制进行了深入的考察,结果表明:(l)提取时序信息既存在逆向串行搜索,又存在顺向串行搜索;(2)早远性判断和新近性判断任务对不同部分时序信息恢复的效应不同,其中早远性判断易化早远部分,新近性判断易化新近部分──表现为对相应部分辨别力的提高和正确反应潜伏期的缩短;(3)在不同的时序信息提取任务中,被试会根据具体条件进行反转反应。  相似文献   
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