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81.
This study examined the effects of visual-verbalload (as measured by a visually presented reading-memory task with three levels) on a visual/auditory stimulus-response task. The three levels of load were defined as follows: "No Load" meant no other stimuli were presented concurrently; "Free Load" meant that a letter (A, B, C, or D) appeared at the same time as the visual or auditory stimulus; and "Force Load" was the same as "Free Load," but the participants were also instructed to count how many times the letter A appeared. The stimulus-response task also had three levels: "irrelevant," "compatible," and "incompatible" spatial conditions. These required different key-pressing responses. The visual stimulus was a red ball presented either to the left or to the right of the display screen, and the auditory stimulus was a tone delivered from a position similar to that of the visual stimulus. Participants also processed an irrelevant stimulus. The results indicated that participants perceived auditory stimuli earlier than visual stimuli and reacted faster under stimulus-response compatible conditions. These results held even under a high visual-verbal load. These findings suggest the following guidelines for systems used in driving: an auditory source, appropriately compatible signal and manual-response positions, and a visually simplified background. 相似文献
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83.
The current study manipulated the visual field and the number of senses of the first character in Chinese disyllabic compounds to investigate how the related senses (polysemy) of the constituted character in the compounds were represented and processed in the two hemispheres. The ERP results in experiment 1 revealed crossover patterns in the left hemisphere (LH) and the right hemisphere (RH). The sense facilitation in the LH was in favor of the assumption of single-entry representation for senses. However, the patterns in the RH yielded two possible interpretations: (1) the nature of hemispheric processing in dealing with sublexical sense ambiguity; (2) the semantic activation from the separate-entry representation for senses. To clarify these possibilities, experiment 2 was designed to push participants to a deeper level of lexical processing by the word class judgment. The results revealed the sense facilitation effect in the RH. In sum, the current study was in support of the single-entry account for related senses and demonstrated that two hemispheres processed sublexical sense ambiguity in a complementary way. 相似文献
84.
This study investigated the effect of isoflavone aglycone (IA) on the learning and memory performance of senescence-accelerated mice, and explored its neural protective mechanism. Results showed that SAM-P/8 senescence-accelerated mice treated with IA performed significantly better in the Y-maze cognitive test than the no treatment control (P<0.05). The cortex AchE activity, serum SOD and GSH-Px activities were notably higher (P<0.05). MDA concentration and the β-secretase activity in the hippocampal tissue were both lower (P<0.05). Additionally, the number of hippocampal neurons was increased and cell morphology was significantly improved. Data suggested that IA could indirectly increase concentration of the cholinergic neural transmitter Ach through regulation of AchE, therefore improving the central cholinergic function and enhancing the learning and memory ability. By reducing the β-secretase activity, IA could decrease the formation and deposition of insoluble Adebris, relieve the resulted toxicity and damage to neurons, and thereby effectively protect the nervous system. 相似文献
85.
Consumer ethics is the moral principles and standards that guide consumers to determine the certain consumption behaviors are ethically right or wrong. Whereas cultural and personal dimensions are crucial constructs affecting individual ethical attitudes and behaviors, few studies consider Confucian dynamism and the role of money in consumer ethics. Confucian dynamism, a cultural dimension based on Confucianism, has played a central role in guiding moral obligations and ethics in human relations in several East Asian countries. Thus, this study tested its hypotheses using a sample of 521 respondents obtained via a systematic random sampling technique. The authors find that individuals with a higher tendency to Confucian dynamism are less tolerant of unethical practices. These findings also show that the role of money partially influences consumer ethical beliefs. Finally, we examine the impact of demographic variables and find age and education affect consideration of ethical values. 相似文献
86.
The purpose of this study was to assess consumer preferences for predictive genetic testing for Alzheimer disease in the United States. A rating conjoint analysis was conducted using an anonymous online survey distributed by Qualtrics® to a general population panel in April 2011 in the United States. The study design included three attributes: Accuracy (40 %, 80 %, and 100 %), Treatment Availability (Cure is available/Drug for symptom relief but no cure), and Anonymity (Anonymous/Not anonymous). A total of 12 scenarios were used to elicit people’s preference, assessed by an 11-point scale. The respondents also indicated their highest willingness-to-pay (WTP) for each scenario through open-ended questions. A total of 295 responses were collected over 4 days. The most important attribute for the aggregate model was Accuracy, contributing 64.73 % to the preference rating. Treatment Availability and Anonymity contributed 20.72 % and 14.59 %, respectively, to the preference rating. The median WTP for the highest-rating scenario (Accuracy 100 %, a cure is available, test result is anonymous) was $100 (mean?=?$276). The median WTP for the lowest-rating scenario (40 % accuracy, no cure but drugs for symptom relief, not anonymous) was zero (mean?=?$34). The results of this study highlight attributes people find important when making the hypothetical decision to obtain an AD genetic test. These results should be of interests to policy makers, genetic test developers and health care providers. 相似文献
87.
Cindy Y. Huang Jessica Costeines Joy S. Kaufman Carmen Ayala 《Journal of child and family studies》2014,23(2):255-262
Rates of teenage pregnancies are higher for African American and Latina adolescents compared to their White peers. African American and Latina adolescent mothers also experience more adversities than their White peers, such as higher rates of depression, school dropout, and economic disadvantage. Furthermore, children of adolescent mothers are at higher risk for adverse development. Parenting stress and social support can impact outcomes experienced by adolescent parents and their children. The present study examined the influence of adolescent mothers’ parenting stress and perceived social support on maternal depression at baseline (6 months after birth), and its impact on infant development 1 year later (18 months after birth). Participants were 180 adolescent mothers of African American or Latino/Hispanic descent. Results suggest that higher levels of parenting stress and less perceived social support were associated with higher levels of depression in the adolescent mothers at baseline. Higher levels of maternal depression were also associated with more developmental delays in infants 1 year post-baseline. Additionally, depression mediated the relationship between parenting stress and later child outcomes. These findings highlight the importance of examining parenting factors such as parenting stress, social support, and maternal depression in ethnic minority adolescent parents, and provide valuable information regarding unique risk and protective factors associated with positive maternal outcomes for ethnic minority adolescent parents and healthy development for their children. 相似文献
88.
以345名12~17岁初中阶段流动儿童为被试,采用问卷法考察学校道德氛围感知在流动儿童父母心理控制与道德推脱关系中的中介作用,以及性别的调节作用。结果表明:(1)父母心理控制正向预测流动儿童道德推脱;(2)学校道德氛围感知在父母心理控制和流动儿童道德推脱之间起到部分中介作用。(3)性别在父母心理控制与学校道德氛围感知间起调节作用,性别调节了中介模型的前半路径,具体而言,与男孩相较,女孩的学校道德氛围感知受到父母心理控制的影响作用更加显著。 相似文献
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90.
已有大量研究揭示了近似数量系统与计算流畅性的相关关系, 但缺少对二者关系原因的系统检验与论证。视觉形状知觉假设有别于传统的数量领域特异性解释, 认为对形状的快速知觉是近似数量系统与计算流畅性的共同认知机制, 即视觉形状的快速知觉能力可以解释二者之间的相关关系。近似数量系统和计算流畅性在加工过程中依赖对形状的快速知觉, 二者在加工过程中都涉及了复杂视觉刺激的快速处理。视觉形状知觉假设得到了一系列研究结果的支持, 但局限在视觉形状知觉与二者关系的探讨上, 视觉形状知觉在二者关系中作用的加工机制仍不清楚。未来研究需要结合多种研究方法和技术, 多角度深入探讨视觉形状知觉在二者关系中作用的认知与脑机制, 并将研究结果应用于数学课堂教学和计算困难的干预中。 相似文献