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201.
GoalTo apply signal processing and machine learning skills and knowledge in processing the EEG and MEG signal and further localize and evaluate the source of the finger stimulation.MethodsCognitive control is usually applied in information processing and behavioral response. In the preprocessing, baseline correction is implemented to analyze the pre-stimuli, combining ERP to mark the event related potential, studying the time-locked only behavior. Z-score transform, coherence and spec trum are calculated and analyzed in the functional connectivity analysis.In addition to the functional analysis, Bayes Optimizer evaluates the neuro imaging according to the hierarchical Bayes. The introduction of the application is described from both user and developer’s prospects. Results: Introduction of both user and developers aspects, on its modules from pre-processing, functional analysis and results visualization and evaluation is conducted with one specific clinical data case, including the correlation is higher especially on gamma band and the MVAR coherence on the whole source space depicting the relation between different regions, especially on somatosensory (compared by thalamus) when stimulated by finger activity, phase-lock property of the E/MEG signal and etc. Compared to a manual selection, the scaling parameter prediction can be improved with support vector machine (SVM). The evaluation results with Bayes Optimization, location prediction is superior in the somatosensory area and in the thalamus, the total reconstructed source space is larger, one of the realization of cognitive system comparing different kernels and classifiers. The SVM and discriminant classifier gives similar results evaluating the dipole localization and the parameter choice related as well to the shape parameter, noise level, hyperprior and etc.ConclusionApproaches of Brain Q are found to be suitable for pre-processing for the EEG and MEG data. The system is capable of functional analysis including coherence and spectral related computation. Machine learning techniques are conducted as well to analyze and evaluate the result of the dipole reconstruction and help to predict the better model parameters and the localization of the origin dipoles. A case on finger stimulation clinical data is conducted and the results of the analysis temporarily and spatially manifests its functionality for users and potential extensions for developers. 相似文献
202.
发展性阅读障碍者的快速命名缺陷 总被引:1,自引:0,他引:1
快速命名任务是一种需要命名多个高熟悉项目的认知任务,尤其适合用来对成因复杂的发展性阅读障碍进行研究。许多研究者使用不同类型的快速命名任务发现,发展性阅读障碍者的快速命名缺陷在眼动过程表现为中央凹和副中央凹的加工困难,在认知过程中表现为抑制能力较差等。未来的研究中应该注意到快速命名缺陷的复杂性,采用多种方法相结合的方式来探究快速命名缺陷的本质,从而建立系统性的假说。 相似文献
203.
客体运动方向的视觉工作记忆容量 总被引:2,自引:0,他引:2
记忆动态场景中多客体的特征和时空信息是人类重要的认知活动。目前有关视觉工作记忆的研究虽然广泛探讨了对视觉信息的存储容量及机制,然而所采用的刺激材料均呈现于静态场景中,且不包含运动信息。而有关多客体追踪的研究只关注动态场景中多客体信息的实时更新,而不涉及一段时间内对客体信息的保持。本研究结合视觉工作记忆领域的变化觉察范式和多客体追踪范式,以独立运动的客体为刺激材料,探讨多个客体的运动方向信息在工作记忆中的存储容量问题。结果表明,在工作记忆中能够存储大约3个客体的运动方向信息。 相似文献
204.
使用模拟研究方法比较了以往研究中提出的基于观察信息矩阵、三明治矩阵的Wald(分别表示为W_Obs、W_Sw)、似然比(Likelihood Ratio)统计量以及新提出的基于经验交叉相乘信息矩阵的Wald统计量(W_XPD)在模型——数据失拟条件下进行项目水平上模型比较时的表现。结果显示:(1)W_Sw的一类错误控制率有很强的健壮性。(2)W_XPD在Q矩阵错误设定的大多数条件下的表现优于W_Sw。结论:模型—数据拟合良好时可以使用W_Sw进行项目水平上的模型比较,当模型与数据失拟时W_XPD可能是更好的选择。 相似文献
205.
206.
A quick eye to anger: An investigation of a differential effect of facial features in detecting angry and happy expressions 下载免费PDF全文
Detection of angry and happy faces is generally found to be easier and faster than that of faces expressing emotions other than anger or happiness. This can be explained by the threatening account and the feature account. Few empirical studies have explored the interaction between these two accounts which are seemingly, but not necessarily, mutually exclusive. The present studies hypothesised that prominent facial features are important in facilitating the detection process of both angry and happy expressions; yet the detection of happy faces was more facilitated by the prominent features than angry faces. Results confirmed the hypotheses and indicated that participants reacted faster to the emotional expressions with prominent features (in Study 1) and the detection of happy faces was more facilitated by the prominent feature than angry faces (in Study 2). The findings are compatible with evolutionary speculation which suggests that the angry expression is an alarming signal of potential threats to survival. Compared to the angry faces, the happy faces need more salient physical features to obtain a similar level of processing efficiency. 相似文献
207.
The goal of this review is to synthesize the data of scientific literature on emotional management and its deficits in chronic pain. We used terms referenced in databases and MesH terms (of the United States National Library of Medicine) to perform a literature search in a powerful online search engine (EBSCOhost research databases). Four hundred and forty-nine papers, taken from international reviews and published of 1994 (because it is in the middle of the 1990s that this theme begins to be handle) to the end of January, 2015, are identified by a total 5 electronic databases with predefined keywords about emotions and chronic pain. Forty-six of which met the inclusion criteria, according to their title, their summary and their complete text. The findings suggest that some emotional management strategies and its deficits can maintain a vicious circle of negative emotional states with physiological and psychopathological consequences. Several studies show that alexithymia, emotional ambivalence and emotional suppression have a deleterious impact on pain, emotional distress (depression, anxiety) and disability. In spite of some contradictions concerning the nature of this effect (sensory or affective pain intensity or even duration of pain), it seems that alexithymia is a major variable implied in chronic pain. Inversely, experiential acceptance has a beneficial effect on psychological distress (depression, anxiety and stress). Emotional disclosure (of stressful or traumatic events) can decrease pain intensity but not disability and mental health. Likewise, emotional expression in daily life seems beneficial, but when the expression of the positive and negative feelings are distinguished, emotional expression of negative feelings increases pain, disability and distress. The whole of these findings emphasize the need to further research about emotional management in chronic non-cancer pain. It is necessary to identify and control the source of potential bias. Some hypotheses have been proposed to explain these findings. In the future, it would be interesting to use a multifactorial approach to investigate the interactions between various processes of emotional management in chronic pain patients. 相似文献
208.
在视觉搜索过程中,老年人是否可以在不同情境下调节自上而下和自下而上的加工水平尚不明确。为了探讨老化对认知灵活性的影响,研究采用空间线索范式,通过比较有效线索和无效线索来考察对线索的注意加工水平(注意捕获、注意抑制),通过比较目标相关和目标无关线索的注意加工水平来考察自上而下和自下而上的作用,通过改变分心物一致性来调控不同的目标凸显情境。结果发现,年轻组在目标非凸显时的空间线索效应高于目标凸显时,表明年轻人会依据目标凸显性调整自上而下的加工水平;但老年组却没有产生这种差异,其更依赖自上而下的加工,注意系统会对目标相关的线索进行注意捕获,对目标无关的线索进行注意抑制。结果表明,随着年龄的增长,认知控制的灵活性下降,表现出对自上而下加工较多的依赖;此外,老年人依然保留着注意捕获和注意抑制的能力,这对认知老化中抑制能力受损的观点提出了挑战。 相似文献
209.
BackgroundTouch screen devices are now ubiquitous, and their usage by young children is increasing. However, the effects of these devices on young children are still unknown. Therefore, this study aimed to address the associations of touch screen device exposure with symptomatic emotional and behavioral problems and language development in children between the ages of 18 and 36 months.MethodA total of 161 primary caregivers of children between the ages of 18 and 36 months were recruited from the pediatric ward and outpatient clinic at a medical center in southern Taiwan. All caregivers were asked to fill out the Child Behavior Checklist for Ages 1½–5 (CBCL 1½–5) and a questionnaire on basic personal information and touch screen device usage, and they were also interviewed with the Communication and Language Screening Test for Birth to Three Chinese-Speaking Infant-Toddlers (CLST). Independent t-test and one-way ANOVA were used to examine the differences among the categories in the demographic variables and to characterize the touch screen device usage behaviors. Pearson’s correlation was used to analyze the relationship between language delay and the extent of touch screen device exposure. After primary univariate analysis, we used multiple regression models to examine the relationships among the effects of touch screen device usage behaviors on children's emotional and behavioral problems and language development.ResultThe children’s mean age was 25.63 months (SD = 5.35). Children who spent more time on touch screen devices were more likely to have emotional problems (β = .219, p < .010, 95 % CI: .279–1.518), anxious/depressive symptoms (β = .206, p < .050, 95 % CI: .170–1.244), somatic complaints (β = .291, p < .001, 95% CI: .455–1.462), social withdrawal symptoms (β = .194, p < .050, 95 % CI: 0.133–1.150), attention problems (β = .300, p < .001, 95 % CI: .432–1.267), and aggressive behaviors (β = .247, p < .010, 95 % CI: .967–3.983). The effects were not noted on language development (β = −.136, p < .100, 95 % CI: −2.595–.147).ConclusionYoung children who spent more time on touch screen devices were more likely to have emotional problems, anxious/depressive symptoms, somatic complaints, social withdrawal symptoms, attention problems, and aggressive behaviors, but not language delay. 相似文献
210.