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41.
Errors in choice tasks are not only detected fast and reliably, participants often report that they knew that an error occurred already before a response was produced. These early error sensations stand in contrast with evidence suggesting that the earliest neural correlates of error awareness emerge around 300 ms after erroneous responses. The present study aimed to investigate whether anecdotal evidence for early error sensations can be corroborated in a controlled study in which participants provide metacognitive judgments on the subjective timing of error awareness. In Experiment 1, participants had to report whether they became aware of their errors before or after the response. In Experiment 2, we measured confidence in these metacognitive judgments. Our data show that participants report early error sensations with high confidence in the majority of error trials across paradigms and experiments. These results provide first evidence for early error sensations, informing theories of error awareness.  相似文献   
42.
This study aims to comprehend traffic safety competencies in high school students from two specific regions of Peru, as well as to analyze the differences between both groups. For this purpose, a qualitative study was carried out which consisted of eight focus groups in high schools, three of them in the metropolitan area of Lima (Lima region) and five in the province of Rodríguez de Mendoza (the Amazonas region). The focus groups were constituted by 73 students enrolled in the last three years of high school, named 3rd, 4th and 5th grade of secondary education, whose ages ranged from 14 to 18 years. The collected data were analyzed employing elements of Grounded Theory and Axiomatic Set Theory. The main findings reveal that most participants have a general understanding of traffic rules and the proper use of the components of traffic safety. Thus, they understand the traffic rules as road signs that regulate the behavior of drivers and pedestrians. In addition, participants know the proper procedure to follow at traffic lights, pedestrian walkways and how to use seat belts. They also identify the driver’s tiredness/drowsiness, and the consumption of alcohol and drugs as potential factors that cause traffic accidents. No causes that are linked to pedestrian behavior were identified, and only participants from the Amazonas region mentioned speeding as a contributing factor. On the other hand, participants report that in practical situations they engage in risky behavior and fail to comply with transit rules. They justify this behavior by citing poor infrastructure, vehicle malfunctions, and the need get around quickly in order to get things done. Finally, the implications of the results are discussed and compared to the content and implementation of the Peruvian Road Safety Educational Program (PENSV, for its acronym in Spanish), providing recommendations that can aid evidence‐based policy making in Peru.  相似文献   
43.
Artificial intelligent systems often model the solutions of typical machine learning problems, inspired by biological processes, because of the biological system is faster and much adaptive than deep learning. The utility of bio-inspired learning methods lie in its ability to discover unknown patterns, and its less dependence on mathematical modeling or exhaustive training. In this paper, we propose a new bio-inspired learning model for a single-class classifier to detect abnormality in video object trajectories. The method uses a simple but dynamic extreme learning machine (ELM) and hierarchical temporal memory (HTM) together referred to as ELM-HTM in an unsupervised way to learn and classify time series patterns. The method has been tested on trajectory sequences in traffic surveillance to find abnormal behaviors such as high-speed, unusual stops, driving in wrong directions, loitering, etc. Experiments have also been performed with 3D air signatures captured using sensors and used for biometric authentication(forged/genuine). The results indicate a significant gain over training time and classification accuracy. The proposed method outperforms in predicting long-time patterns by observing small steps with an average accuracy gain of 15% as compared to the state-of-the-art HTM. The method has applications in detecting abnormal activities in videos by learning the movement patterns as well as in biometric authentication.  相似文献   
44.
隐藏情绪识别对公共安全防范与预警具有重要的意义。微表情是揭示隐藏情绪的一条重要通道。但目前隐藏情绪研究较少且微表情因其细微幅度与快速出现等特性难以识别, 其研究尚未在实际中广泛应用。因为, 隐藏情绪的认知与表达机理亟需系统的研究,采集实际场景中的微表情数据, 并以脑电信号辅助微表情的精确标注是提高微表情标注效率的有效途径。深入研究微表情识别方法, 并辅以人脸颜色、注视估计和非接触生理信号等多通道数据, 以检测与识别隐藏情绪。社会公共安全是隐藏情绪分析和识别的典型场景。面向精神疾病患者两害行为(即危害自身或他人的危险行为)风险评估和服刑人员会见场景隐藏情绪检测, 可以有效地对相应系统和方法进行验证和修正。  相似文献   
45.
近期发现,采用目标探测任务作为二级任务时,目标探测条件不仅不会削弱,甚至会提高记忆成绩,产生注意促进效应(ABE)。为进一步探究目标探测的作用机制,研究采用事件相关电位(ERP)技术,对比目标与分心条件在编码和提取过程中所诱发的ERP差异。结果表明,两类条件在再认过程中所诱发的ERP差异不仅表现在早期与知觉加工相关的ERP成份上,并且一直持续到了后期与细节提取相关的ERP成分上。由此推测,ABE不仅体现在编码早期的知觉加工阶段,更会延续到后期的复述与精加工。  相似文献   
46.
变化盲视是指在某些条件下人们往往觉察不到视觉场景中实质性的改变。最近研究表明,变化盲视发生时个体虽然不能有意识地报告变化,但却能无意识地对变化刺激进行加工和反应,也就是产生了内隐觉察。内隐觉察能够引导注意、影响反应速度。与觉察和无觉察相比,内隐觉察的眼动模式具有鲜明的特征。与无变化试次相比,盲视试次可以观察到显著的脑电活动变化以及不同的脑区激活。内隐觉察的研究虽然取得了丰富的成果,但也还存在着一些需要明确和解决的问题,如左侧前额叶在内隐觉察中的作用,以及如何将没有视觉干扰的范式应用到变化觉察的神经活动测量中等。  相似文献   
47.
Background/Objective: This study aims to characterize the differences on the short-term temporal network dynamics of the undirected and weighted whole-brain functional connectivity between healthy aging individuals and people with mild cognitive impairment (MCI). The Network Change Point Detection algorithm was applied to identify the significant change points in the resting-state fMRI register, and we analyzed the fluctuations in the topological properties of the sub-networks between significant change points. Method: Ten MCI patients matched by gender and age in 1:1 ratio to healthy controls screened during patient recruitment. A neuropsychological evaluation was done to both groups as well as functional magnetic images were obtained with a Philips 3.0T. All the images were preprocessed and statistically analyzed through dynamic point estimation tools. Results: No statistically significant differences were found between groups in the number of significant change points in the functional connectivity networks. However, an interaction effect of age and state was detected on the intra-participant variability of the network strength. Conclusions: The progression of states was associated to higher variability in the patient's group. Additionally, higher performance in the prospective and retrospective memory scale was associated with higher median network strength.  相似文献   
48.
49.
For scientific knowledge to be trustworthy, it needs to be dissociated from material interests. Disinterested research also performs other important non-instrumental roles. In particular, academic science has traditionally provided society with reliable, imaginative public knowledge and independent, self-critical expertise. But this type of science is not compatible with the practice of instrumental research, which is typically proprietary, prosaic, pragmatic and partisan. With ever-increasing dependence on commercial or state funding, all modes of knowledge production are merging into a new, ‘post-academic’ research culture which is dominated by utilitarian goals. Growing concern about conflicts of interest is thus a symptom of deep-seated malaise in science and medicine. An expanded version of this paper was presented at an International Conference on “Conflict of Interest and its Significance in Science and Medicine” held in Warsaw, Poland on 5–6 April, 2002.  相似文献   
50.
Professional autonomy is often described as a claim of professionalsthat has to serve primarily their own interests. However, it can also beseen as an element of a professional ideal that can function as astandard for professional, i.e. medical practice. This normativeunderstanding of the medical profession and professional autonomy facesthree threats today. 1) Internal erosion of professional autonomy due toa lack of internal quality control by the medical profession; 2)the increasing upward pressure on health care expenses that calls for ahealth care policy that could imply limitations for the professionalautonomy of physicians; 3) a distorted understanding of theprofession as being based on a formal type of knowledge and relatedtechnology, in which other normative dimensions of medical practice areneglected and which frustrates meaningful communication betweenphysicians and patients. To answer these threats a normative structureanalysis of medical practice is presented, that indicates whichprinciples and norms are constitutive for medical practice. It isconcluded that professional autonomy, normatively understood, should bemaintained to avoid the lure of the technological imperative and toprotect patients against third parties' pressure to undertreatment.However, this professional autonomy can only be maintained if members ofthe profession subject their activities and decisions to a criticalevaluation by other members of the profession and by patients and ifthey continue to critically reflect on the values that regulate today'smedicine.  相似文献   
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