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261.
立体视觉的心理物理和VEP比较研究   总被引:2,自引:0,他引:2  
心理物理试验是研究立体视觉的主要方法。70年代VEP开始用于体视研究,并取得许多结果。由于VEP信号复杂,这些结果不能令人满意。本文使用心理物理试验和VEP对比方法对体视加以研究。我们的结果是:VEP波形中第一个正峰与刺激图形的亮度有关;N_2峰和P_3峰的潜伏期对判断体视存在与否有重要价值;本试验确定N_2峰潜伏期在体视存在时约为240ms—280ms,无体视存在时约为290ms—310ms;P_3峰潜伏期在体视存在时约为280ms—310ms,无体视存在时约为340ms—360ms;体视存在时的VEP与无体视存在时的VEP的互相关系数小于0.1;有体视的VEP其功率谱密度在8Hz附近有一峰;心理物理试验中使用强制选择得到的结果从VEP波形比较中可以确认是可靠的;有体视的VEP其N_2和P_3的潜伏期随视差变化呈现规律性改变。  相似文献   
262.
一般认为,突触传递的长时程增强(Long-term potentiation,LTP)可能是学习和记忆的神经基础。我室的系列工作表明,大鼠在条件性行为的建立中,海马齿状回、CA_3、CA_1区均出现LTP样变化,并将之称为习得性LTP(Learning-de-pendent LTP),而且发现每次训练作业后突触效应的增强,经一段时间(4小时)后就  相似文献   
263.
量词肯定句和否定句的理解   总被引:6,自引:2,他引:4  
缪小春  桑标 《心理学报》1992,25(3):10-17
本研究试图探索人们对舍有“所有”、“每一个”、“有一些”等量词的肯定句、否定句和双重否定句的理解。要求成人被试尽快判断呈现在计算机屏幕上的句子和哪一幅图画的内容相符。结果表明,影响反应时的因素为(1)句子的表层结构和它的底层意义的一致程度;(2)句子的意义和从图画中得出的命题的一致程度;(3)句子中使用的量词。结果还表明,否定句的判断时间不一定全都比肯定句的长。  相似文献   
264.
265.
The construct accessibility model (CAM) holds that constructs are most likely to influence behavior when they are accessible in memory. While the theory of reasoned action sees intention as an important determinant of behavior, the CAM predicts that the intention to act upon a given health behavior is not likely to be acted upon unless the intention is in an accessible state. Therefore, people who frequently talk about or think about using condoms are likely to have condom related constructs available and use them when needed. This paper reports findings from the pilot phase of a project to identify beliefs which influence condom use in Hispanic and African-American youth living in Detroit. 15 male and 15 female Hispanics and 17 male and 17 female African-Americans aged 15-21 years of mean and median age 18.5, were interviewed face-to-face in 1989 with the goal of identifying condom beliefs which may influence their condom use. 80-82% of male participants, 53% of Hispanic females, and 100% of Black females had experienced sexual intercourse, with age at first intercourse ranging between 13.1 and 16.5 years. 88% of Black women and 7% of Hispanic women were pregnant at the interview. Regarding participants' level of preventive knowledge, all but 1 recently immigrated Hispanic female knew HIV was transmitted by needles and sexual intercourse. 87% of Hispanics and 94% of African-Americans responded that condoms protect against AIDS, but only 13% of Hispanics and 47% of African-Americans knew that nonlatex condoms do not. Some participants expressed concern that condoms reduce sensitivity and/or break during intercourse. Controlling for sexual activity, 25% of Hispanic females, 83% of Hispanic males, 71% of African-American females, and 80% of African-American males had ever used a condom; no Hispanic and 14% of Blacks reported using them consistently in the 12 month period preceding the interview. With 100% of African-American males and 97% of Black females reporting thinking about using condoms compared to 80% of Hispanics, the study findings suggest that condom intentions are more accessible in African-Americans than among Hispanics.  相似文献   
266.
Hispanic Americans have one of the highest rates of HIV seroprevalence among all ethnics groups in the US, with high rates being especially noticeable among women and children. Were it known which cultural factors have the most influence on whether Hispanics engage in high-risk behavior for HIV transmission, prevention interventions could be targeted accordingly. To that end, this study was mounted to identify which Hispanic cultural factors relate to condom use. 117 males and 73 females aged 17-56 years of mean age 25.67 were surveyed in Washoe county, Nevada. These mostly young adults had recently immigrated to the western US. It was initially posited that fate orientation, male- female relationships, family relationships, machismo behavior, and religion would have equal influence with respect to condom use. Analysis found that condom use was largely associated with and determined by men who are the principal buyers of condoms. A machismo attitude toward protecting women by using condoms was also associated with condom use. Neither fate orientation with respect to AIDS, nor religion were important determinants of condom use, even though 86.5% of the respondents were Catholic. The degree to which respondents adhered to traditional Hispanic cultural values was influenced by the degree of education and acculturation. On the basis of these findings, the authors suggest targeting AIDS prevention messages to males, while emphasizing the protection of women through condom use. They also suggest that both education and acculturation levels be assessed before implementing prevention programs.  相似文献   
267.
The Australian study investigated condom-specific assertiveness and condom use as a means of prevention infection from sexually transmitted diseases. 211 men participated including 83 homosexual men (aged 19-62 years) and 128 heterosexual men (aged 17-49) who completed a questionnaire that comprised demographic details such as age, monogamy, and sexual activity as well as attitudinal and assertiveness measures. General assertiveness was measured by the Rathus Assertiveness Schedule (RAS) which had been widely used across a wide range of social situations. Assertiveness relating specifically to situations involving condoms was measured by the Condom Assertiveness Scale (CAS). Intention to use condoms was positively related to favorable attitudes, which were related to condom-specific assertiveness for both groups. For the heterosexual men only, general social assertiveness was negatively related to attitudes toward condoms. For both groups, the condom-specific measure of assertiveness was positively correlated with attitudes toward condoms. Condom-specific assertiveness was positively related to general social assertiveness as measured by the Rathus Assertiveness Schedule for the homosexual, but not for the heterosexual men. The negative relationship between general assertiveness and attitude to condoms among the heterosexual men implies that the risk reducing behavior of condom use did not seem to accord with the perceptions of masculinity and social assertiveness among heterosexual men. Thus, female partners of such heterosexual men exhibiting negative attitudes toward condom use combined with assertiveness would have to overcome resistance to insist on the use of condoms. Recently some advertising campaigns have been directed at women. The promotion of condom use among heterosexual men has to deal with the perceptions of condom use as unmasculine behavior.  相似文献   
268.
以发生认识论者自称的皮亚杰不仅把人类认识的发展过程推向了一个新水平,而且给心理学的发展引进了一场范式的革命。皮亚杰认知发展心理学理论的最大优势在于:它能为个体心理发展的共性本质提供一个简洁而一致的解释,而且,以此理论为基础而设计的许多实验得到了大量有关数据,其中大部分支持皮亚杰的理论假设。然而,皮亚杰以结构建构论为基础的能力阶段模式本身,也是发展心理学建构发展过程中的一部分,它本身也是处于不断的同化和顺应、不断的平衡化过程之中的。  相似文献   
269.
一曾经为社会主义建设和社会主义改造,为满足人民生活需要和解决城市就业,为对外开放、出口创汇立下了汗马功劳的城镇集体家具企业,近几年来的日子越来越难过,木制家具企业更甚。据对江苏轻工系统39个城镇集体家具企业调查,1986年工业总产值  相似文献   
270.
交往·主体间性·客观性   总被引:6,自引:0,他引:6  
本文考察了主体问性作为经验现象和哲学范畴在科学认识活动和近现代哲学中是怎样出现的,指出它本质上是一种由生产和交往形成的社会关系和结构的特殊类型,具体表现为实践一认识活动中的相互性、协同性和调节原则。这种社会性是实现认识、知识客观性的一个逻辑上独立的必要条件和根据。由此也可以看到认知和评价的两种理性态度在起源和抽象形式上的一致性。  相似文献   
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