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121.
122.
This article examines the theoretical basis of decision-making deficits exhibited by cocaine abusers in a laboratory decision-making
task first described by Bechara, Damasio, Damasio, and Anderson (1994). A total of 12 male cocaine abusers and 14 comparison
subjects performed the task, and the cocaine group performed significantly worse than the comparison group. A cognitive modeling
analysis (Busemeyer & Stout, 2002) was used to estimate three parameters that measure importance of the cognitive, motivational,
and response processes for determining the observed performance deficit. The results of this analysis indicated, for the first
time, that motivational and choice consistency factors, but not learning/ memory were mainly responsible for the decision-making
deficit of the cocaine abusers in this task. 相似文献
123.
The authors explored the temporal mechanism of attention deficit in children with attention-deficit/hyperactivity disorder (ADHD). In rapid serial visual presentation tasks in which two targets (T-sub-1 and T-sub-2) were presented in close temporal proximity among distractors, participants tried to identify T-sub-1 and detect T-sub-2 in one (dual-task) experiment and only to detect T-sub-2 in a second control (single-task) experiment. The sensitivity of T-sub-2 detection was analyzed using signal detection theory. The attentional blink--the impairment in T-sub-2 detection following the identification of T-sub-1--was increased in magnitude and protracted in the patients. Moreover, some ADHD children appeared to have a blink largely normal in magnitude but temporally displaced toward a later time. The authors hypothesize that a slower closing of the attention gate may mediate this specific attention impairment in ADHD children. 相似文献
124.
The purpose of this study was to explore adolescents' perceptions and attitudes regarding the Internet, by gender. Data were collected from 636 high school students in Taiwan. It was found that male adolescents perceived the Internet more as a "toy," while female adolescents perceived the Internet more as a "technology," "tool" or "tour." Results indicated that females held more pragmatic views of the Internet, whereas males believed they could obtain more enjoyment from the Internet. In addition, males expressed significantly more positive attitudes than did females on two aspects of the Internet: usefulness and perceived control. However, no significant gender differences were found in terms of the affection and behavior aspects of using the Internet. More importantly, females tended to show higher Internet self-efficacy than did males. It is suggested that gender differences regarding the Internet might be narrowing because female adolescents are acquiring more experience with it. 相似文献
125.
A problem with interpretations of differences in mathematic achievement between students from Asian countries and those from the United States is the seemingly implicit assumption of the cultural homogeneity of Asian societies. Researchers rarely measure the effects of variables within cultures that are hypothesized to be related to differences across cultures. In the present study, the authors examined the effects of socioeconomic status (SES) and quality of instruction on Chinese students' (1st, 3rd, and 5th grades) understanding of distance, time, and speed. The results indicated that (a) low SES in China can impede the development of children's mathematical cognition and (b) higher SES does not guarantee better performance. The implication is that the gap in mathematical performance between socioeconomically advantaged and disadvantaged children can be narrowed or even eliminated through instructional practices that focus on the systematic training of children's mathematical thinking. 相似文献
126.
Limits on theory of mind use in adults 总被引:10,自引:0,他引:10
127.
128.
分析中国伪生命科学产生的文化原因和背景,指出其致命的谎言、骗术与危害;揭露其理论上的荒谬与科学上的无知。并强调开展对这类伪科学产品进行批判运动的意义;同时重新对科学、非科学、伪科学、宗教、神话、迷信等进行划界和定义。医学研究需要正义、需要哲学的引导;在事实的世界之上,必须由价值和意义的世界来把握;医学理论不允许任意杜撰和加工,从这个意义上,医学科学还需要法律来维护其正义 相似文献
129.
现行《医疗事故处理办法》颁布实施10 年之久,新形势下需要对其进行修改和完善。“办法”的修改应该体现平等保护医患双方合法权益原则,合理界定医疗事故范围,调整医疗事故鉴定委员会的组成,建立完善的证据管理制度,明确医疗事故损失赔偿的范围和额度。 相似文献
130.
汉字词识别过程的形,音,义编码作用的研究 总被引:7,自引:0,他引:7
本文通过两个实验,采用汉字词形、音、义特征匹配任务,探讨了影响汉字词的形、音、义编码与提取方式的有关因素。实验一发现在速示条件下,对汉字词再认的成绩并不受字词的使用度的影响,反应时无明显变化,而主要受编码加工的深度影响。在形、音、义特征加工中,对音码的加工时间最长,再认的正确率最低;义码的加工时间较短,再认正确率最高;形码的反应时及再认成绩介于音码与义码之间。实验二在非速示条件下也获得了相同的结果。研究结果表明,在汉字词的形、音、义特征中,存在着编码加工深度的差异。 相似文献