Information flow

信息流
  • 文章类型: Journal Article
    工作记忆在认知科学中起着重要的作用,是学习的基本过程。虽然工作记忆在容量和持续时间方面受到限制,不同的认知任务旨在克服这些困难。这项研究调查了一项新颖的视觉工作记忆任务中的信息流,在该任务中,参与者对夸张和正常的图片做出反应。十名健康男性(平均年龄28.5±4.57岁)参加了编码和检索任务的两个阶段。记录脑电图(EEG)信号。此外,自适应定向传递函数(ADTF)方法用作计算工具,以研究从EEG信号中提取的事件相关电位(ERP)的视觉工作记忆检索的动态过程。网络连接和P300子组件(P3a、P3b,和LPC)也在视觉工作记忆检索过程中提取。然后,将非参数Wilcoxon检验和五个分类器应用于网络属性,以在夸大的旧图片和正常的旧图片之间进行特征选择和分类。Ge的Z值比其他网络性质更独特。在机器学习方面,准确性,F1分数,和k最近邻(KNN)的特异性,分类器为81%,77%,81%,分别。与其他分类器相比,KNN分类器排名第一。此外,入度/出度矩阵的结果表明,在检索夸张图片时,信息在右半球不断流动,从P3a到P3b。在视觉工作记忆的检索过程中,与正常图片相比,与注意力过程相关的网络对夸大的图片显示出更大的激活。这表明,夸张的图片可能吸引了更多的注意力,因此需要更多的认知资源进行检索。
    Working memory plays an important role in cognitive science and is a basic process for learning. While working memory is limited in regard to capacity and duration, different cognitive tasks are designed to overcome these difficulties. This study investigated information flow during a novel visual working memory task in which participants respond to exaggerated and normal pictures. Ten healthy men (mean age 28.5 ± 4.57 years) participated in two stages of the encoding and retrieval tasks. The electroencephalogram (EEG) signals are recorded. Moreover, the adaptive directed transfer function (ADTF) method is used as a computational tool to investigate the dynamic process of visual working memory retrieval on the extracted event-related potentials (ERPs) from the EEG signal. Network connectivity and P300 sub-components (P3a, P3b, and LPC) are also extracted during visual working memory retrieval. Then, the nonparametric Wilcoxon test and five classifiers are applied to network properties for features selection and classification between exaggerated-old and normal-old pictures. The Z-values of Ge is more distinctive rather than other network properties. In terms of the machine learning approach, the accuracy, F1-score, and specificity of the k-nearest neighbors (KNN), classifiers are 81%, 77%, and 81%, respectively. KNN classifier ranked first compared with other classifiers. Furthermore, the results of in-degree/out-degree matrices show that the information flows continuously in the right hemisphere during the retrieval of exaggerated pictures, from P3a to P3b. During the retrieval of visual working memory, the networks associated with attentional processes show greater activation for exaggerated pictures compared to normal pictures. This suggests that the exaggerated pictures may have captured more attention and thus required greater cognitive resources for retrieval.
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  • 文章类型: Journal Article
    类比用于使抽象主题有意义,并且更容易被学习者理解。将简单的类比纳入STEM教室是一种相当普遍的做法,但是类比通常是由讲师为学习者生成和解释的。我们假设挑战学习者创造复杂的,扩展类比本身可以促进内容知识的整合和批判性思维技能的发展,这对深度学习至关重要,但对教学具有挑战性。在这项定性研究中,大学生物学学生(n=30)被要求使用熟悉的项目构建一个关于基因信息流的复杂类比。一周后,参与者对同一主题进行了第二个类比,但这一次使用更具挑战性的项目。二十名参与者成对进行了具有挑战性的类比,而其他10人独自工作。对50次访谈的分析得出了一个新颖的评分方案,它测量了内容知识(对生物学术语的理解)和批判性思维(类比元素之间关系的对齐)。大多数参与者由于练习而略有改善,但是与合作伙伴一起工作时,它们得到了显着改善。最大的收获是批判性思维,不是内容知识。让学生构建复杂的,成对复杂的类比是一种高影响力的实践,可以帮助学生发展他们的批判性思维能力,在学术和专业环境中至关重要。合作伙伴之间的讨论可能要求学生证明他们的解释和批评他们的合作伙伴的解释,这是批判性思维的特征。
    Analogies are used to make abstract topics meaningful and more easily comprehensible to learners. Incorporating simple analogies into STEM classrooms is a fairly common practice, but the analogies are typically generated and explained by the instructor for the learners. We hypothesize that challenging learners to create complex, extended analogies themselves can promote integration of content knowledge and development of critical thinking skills, which are essential for deep learning, but are challenging to teach. In this qualitative study, college biology students (n = 30) were asked to construct a complex analogy about the flow of genetic information using a familiar item. One week later, participants constructed a second analogy about the same topic, but this time using a more challenging item. Twenty participants worked on the challenging analogy in pairs, while the other 10 worked alone. Analysis of the 50 interviews resulted in a novel-scoring scheme, which measured both content knowledge (understanding of biology terms) and critical thinking (alignment of relationships between elements of the analogy). Most participants improved slightly due to practice, but they improved dramatically when working with a partner. The biggest gains were seen in critical thinking, not content knowledge. Having students construct complex, sophisticated analogies in pairs is a high-impact practice that can help students develop their critical thinking skills, which are crucial in academic and professional settings. The discussion between partners likely requires students to justify their explanations and critique their partner\'s explanations, which are characteristics of critical thinking.
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  • 文章类型: Journal Article
    触觉对于我们与外部物体的互动和手部动作的精细控制至关重要。尽管对人体体感加工进行了广泛的研究,在处理触觉信息时,所涉及的大脑区域如何作为动态网络进行交互仍然难以捉摸。很少有研究探讨体感信息流的时间动态,并报告了不一致的结果。这里,我们通过磁源成像和皮质-皮质耦合动力学检查了皮质体感处理。我们记录了单侧气动刺激期间典型发育儿童的脑磁图信号。通过动态统计参数映射来映射体感诱发场的神经活动,用时空激活分析评估,并由格兰杰因果关系建模。单侧气动刺激在对侧主要和次要体感区域引起明显且一致的激活,但在同侧主要和次要体感区域引起较弱且不一致的激活。还一致观察到对侧初级运动皮层和上脑回的激活。时空激活和Granger因果关系分析揭示了从对侧主回到上回的初始序列信息流,对侧初级运动皮层,和对侧次级和后来的动态和并行信息在一致激活的对侧皮质区域之间流动。我们的研究揭示了正常发育大脑中皮层体感加工的时空动力学。
    Sense of touch is essential for our interactions with external objects and fine control of hand actions. Despite extensive research on human somatosensory processing, it is still elusive how involved brain regions interact as a dynamic network in processing tactile information. Few studies probed temporal dynamics of somatosensory information flow and reported inconsistent results. Here, we examined cortical somatosensory processing through magnetic source imaging and cortico-cortical coupling dynamics. We recorded magnetoencephalography signals from typically developing children during unilateral pneumatic stimulation. Neural activities underlying somatosensory evoked fields were mapped with dynamic statistical parametric mapping, assessed with spatiotemporal activation analysis, and modeled by Granger causality. Unilateral pneumatic stimulation evoked prominent and consistent activations in the contralateral primary and secondary somatosensory areas but weaker and less consistent activations in the ipsilateral primary and secondary somatosensory areas. Activations in the contralateral primary motor cortex and supramarginal gyrus were also consistently observed. Spatiotemporal activation and Granger causality analysis revealed initial serial information flow from contralateral primary to supramarginal gyrus, contralateral primary motor cortex, and contralateral secondary and later dynamic and parallel information flows between the consistently activated contralateral cortical areas. Our study reveals the spatiotemporal dynamics of cortical somatosensory processing in the normal developing brain.
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  • 文章类型: Journal Article
    神经元集合之间的交流如何塑造功能性大脑动力学是神经科学的基本问题。大脑中的交流可以被视为节点活动与这些活动流动的结构网络相互作用的产物。对这些相互作用的研究是,然而,受限于难以描述大脑的复杂动态。因此,有必要开发一些方法来研究这些网络-动态相互作用以及它们如何影响信息流,而不必先验地确定动力学或诉诸限制性分析方法。这里,我们采用了最近建立的基于扰动的网络分析方法,这是一个神经科学环境,研究大脑中的信息流如何从潜在结构的特性中产生。为了证明概念,我们将该方法应用于计算机全脑模型。我们阐述了捕获网络动态相互作用的度量分布的功能含义,称为净影响和流量。我们还研究了静息状态网络级别的网络动力学相互作用。这种方法的一个吸引人的特点是它的简单,它允许直接转化为实验或临床环境,例如用于确定刺激研究或治疗干预的目标。
    在这项工作中,我们使用计算机模拟中的受控扰动来识别影响和调节活跃大脑网络中信息流的区域。识别此类区域的常规方法需要对描述节点动力学的数学模型进行广泛的分析处理,因此,它的范围仅限于已经定义了这种模型的系统。所提出的形式主义可以通过简单地测量对扰动的响应来识别具有动态和功能重要性的区域,因此可以应用于任何可以扰动区域的尺度,并且没有任何关于节点动态的先决条件信息。此外,度量与区域间通信的关系,功能能力,和结构-功能映射通常为它们提供了相当大的实践重要性,特别是确定治疗干预的目标。
    How communication among neuronal ensembles shapes functional brain dynamics is a question of fundamental importance to neuroscience. Communication in the brain can be viewed as a product of the interaction of node activities with the structural network over which these activities flow. The study of these interactions is, however, restricted by the difficulties in describing the complex dynamics of the brain. There is thus a need to develop methods to study these network-dynamical interactions and how they impact information flow, without having to ascertain dynamics a priori or resort to restrictive analytical approaches. Here, we adapt a recently established network analysis method based on perturbations, it to a neuroscientific setting to study how information flow in the brain can raise from properties of underlying structure. For proof-of-concept, we apply the approach on in silico whole-brain models. We expound on the functional implications of the distributions of metrics that capture network-dynamical interactions, termed net influence and flow. We also study the network-dynamical interactions at the level of resting-state networks. An attractive feature of this method is its simplicity, which allows a direct translation to an experimental or clinical setting, such as for identifying targets for stimulation studies or therapeutic interventions.
    In this work, we use controlled perturbations in silico to identify regions that influence and mediate information flow in active brain networks. Conventional approaches of identifying such regions require the extensive analytical treatment of mathematical models describing node dynamics, thus restricting its scope only to systems where such models have been defined. The presented formalism can identify regions of dynamical and functional importance by simply measuring responses to perturbations, and can thus be applied at any scale where regions can be perturbed, and without any prerequisite information about node dynamics. Furthermore, the relation of metrics to interregional communication, functional capabilities, and structure-function mapping in general affords them considerable practical importance, especially for identifying targets for therapeutic interventions.
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    文章类型: Preprint
    人脑是一个海量的信息产生和处理机器。研究信息流可以提供对脑功能和脑疾病的独特见解。我们在这里提供一种使用fMRI绘制整个大脑中区域信息流的工具。使用该工具,我们可以估计从一个区域到大脑其余部分的信息流,在不同地区之间,在不同的日子之间,或不同个体的大脑之间。
    Human brain is a massive information generation and processing machine. Studying the information flow may provide unique insight into brain function and brain diseases. We present here a tool for mapping the regional information flow in the entire brain using fMRI. Using the tool, we can estimate the information flow from a single region to the rest of the brain, between different regions, between different days, or between different individuals\' brain.
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  • 文章类型: Journal Article
    对于应用于蛋白质的高斯网络模型的Langevin方程,给出了明确的解析解。随机和确定性周期力。推导了时间相关函数的同步和异步分量,并获得了残差对的时间相关性中的相位差表达式。同步组件能够确定蛋白质结构内的动态群落。异步组件揭示了因果关系,其中,残基i和j之间的时间相关函数取决于是否在j之前观察到i或反之亦然,导致定向信息流。亲环蛋白A和人NAD依赖性异柠檬酸脱氢酶的变构过程中的驱动和驱动残基是通过扰动扫描技术确定的。影响残留物波动之间相位差的因素,如网络拓扑,连通性,和残留物中心性,被识别。在各向同性高斯网络模型的约束下,我们的结果表明,异步性随着粘度和残留物之间的距离而增加,随着连接性的增加而减少,并随着特征向量中心性水平的增加而减小。
    An explicit analytic solution is given for the Langevin equation applied to the Gaussian Network Model of a protein subjected to both a random and a deterministic periodic force. Synchronous and asynchronous components of time correlation functions are derived and an expression for phase differences in the time correlations of residue pairs is obtained. The synchronous component enables the determination of dynamic communities within the protein structure. The asynchronous component reveals causality, where the time correlation function between residues i and j differs depending on whether i is observed before j or vice versa, resulting in directional information flow. Driver and driven residues in the allosteric process of cyclophilin A and human NAD-dependent isocitrate dehydrogenase are determined by a perturbation-scanning technique. Factors affecting phase differences between fluctuations of residues, such as network topology, connectivity, and residue centrality, are identified. Within the constraints of the isotropic Gaussian Network Model, our results show that asynchronicity increases with viscosity and distance between residues, decreases with increasing connectivity, and decreases with increasing levels of eigenvector centrality.
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  • 文章类型: Journal Article
    在特定行为期间跨大脑区域的神经活动的协调通常被解释为参与控制行为的神经沟通。然而,与行为相关的信息是否实际上在区域之间传输通常是未经测试的。这里,我们使用信息理论工具来量化运动皮层和纹状体如何编码和交换有关大鼠技能学习过程中特定的达到掌握运动特征的行为相关信息.我们发现在技能学习过程中,行为相关信息的编码发生了时间偏移,以及行为相关信息流的主要方向的逆转,从幼稚运动期间的皮层到纹状体到熟练运动期间的纹状体到皮层。量化学习过程中整体神经活动的演变的标准分析方法-例如神经信号幅度的变化或区域之间的整体信息交换-未能捕获这些行为相关的信息动态。使用这些标准方法,相反,我们发现在运动产生过程中整体神经信号的一致共激活,并且在学习过程中区域之间的整体信息传播双向增加.我们的结果表明,技能学习是通过行为相关信息如何在皮质和皮质下脑区域传递的转变来实现的,并且隔离与行为相关的神经活动成分和有关行为的信息对于发现协同和协调网络中的定向相互作用至关重要。
    The coordination of neural activity across brain areas during a specific behavior is often interpreted as neural communication involved in controlling the behavior. However, whether information relevant to the behavior is actually transferred between areas is often untested. Here, we used information-theoretic tools to quantify how motor cortex and striatum encode and exchange behaviorally relevant information about specific reach-to-grasp movement features during skill learning in rats. We found a temporal shift in the encoding of behaviorally relevant information during skill learning, as well as a reversal in the primary direction of behaviorally relevant information flow, from cortex-to-striatum during naive movements to striatum-to-cortex during skilled movements. Standard analytical methods that quantify the evolution of overall neural activity during learning-such as changes in neural signal amplitude or the overall exchange of information between areas-failed to capture these behaviorally relevant information dynamics. Using these standard methods, we instead found a consistent coactivation of overall neural signals during movement production and a bidirectional increase in overall information propagation between areas during learning. Our results show that skill learning is achieved through a transformation in how behaviorally relevant information is routed across cortical and subcortical brain areas and that isolating the components of neural activity relevant to and informative about behavior is critical to uncover directional interactions within a coactive and coordinated network.
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  • 文章类型: Journal Article
    具有复杂细胞结构和来自虚拟环境的闭环反馈的人脑类器官可以提供对认知基础神经机制的见解。然而,具有某些认知能力的类器官也可能值得道德考虑。已经提出了一种预防方法来解决这些伦理问题,方法是关注认识论问题,即类器官是否具有与人类大脑相似的道德相关能力的神经结构。评论家挑战这种哲学上的相似性方法,科学,和实际理由,但这样做没有合适的替代方案。这里,我介绍了一种架构方法,该方法根据通过系统的信息流模式来推断大脑类器官中类似认知处理的潜力。然后,由类器官获得的那种计算架构告知了可能的认知能力,理论上,得到支持和实证调查。讨论了这种方法对大脑类器官的道德考虑能力的影响。
    Human brain organoids equipped with complex cytoarchitecture and closed-loop feedback from virtual environments could provide insights into neural mechanisms underlying cognition. Yet organoids with certain cognitive capacities might also merit moral consideration. A precautionary approach has been proposed to address these ethical concerns by focusing on the epistemological question of whether organoids possess neural structures for morally-relevant capacities that bear resemblance to those found in human brains. Critics challenge this similarity approach on philosophical, scientific, and practical grounds but do so without a suitable alternative. Here, I introduce an architectural approach that infers the potential for cognitive-like processing in brain organoids based on the pattern of information flow through the system. The kind of computational architecture acquired by an organoid then informs the kind of cognitive capacities that could, theoretically, be supported and empirically investigated. The implications of this approach for the moral considerability of brain organoids are discussed.
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  • 文章类型: Journal Article
    目的:单光子发射计算机断层扫描(SPECT)和立体脑电图(SEEG)是用于治疗耐药局灶性癫痫患者的诊断技术。虽然发作性SPECT研究中的高灌注模式揭示了癫痫发作的发作和传播途径,ictal低灌注的作用仍然知之甚少。这项研究的目的是使用立体EEG记录系统地表征不同灌注的大脑区域之间的时空信息流动力学。
    方法:我们确定了切除性癫痫手术后无癫痫发作的患者,这些患者之前进行了SPECT和SEEG检查。我们估计了癫痫发生区(EZ)之间的定向连通性,未切除的过度灌注区域,灌注不足,和间期的基线灌注,预先发作,ictal,和后期。
    结果:与背景相比,我们注意到在从EZ到基线和超灌注区域的前期有显著的信息流(1),(2)在从EZ到所有三个区域的发作期间,(3)在癫痫发作从灌注不足区域到所有三个区域的演变期间。
    结论:发现低灌注脑区在发作期与EZ间接相互作用。
    结论:我们独特的研究,结合颅内电生理和灌注成像,提供了令人信服的证据,表明在从发作间期到发作期状态的过渡过程中,大脑区域之间的方向连通性发生了动态变化。
    OBJECTIVE: Ictal Single Photon Emission Computed Tomography (SPECT) and stereo-electroencephalography (SEEG) are diagnostic techniques used for the management of patients with drug-resistant focal epilepsies. While hyperperfusion patterns in ictal SPECT studies reveal seizure onset and propagation pathways, the role of ictal hypoperfusion remains poorly understood. The goal of this study was to systematically characterize the spatio-temporal information flow dynamics between differently perfused brain regions using stereo-EEG recordings.
    METHODS: We identified seizure-free patients after resective epilepsy surgery who had prior ictal SPECT and SEEG investigations. We estimated directional connectivity between the epileptogenic-zone (EZ), non-resected areas of hyperperfusion, hypoperfusion, and baseline perfusion during the interictal, preictal, ictal, and postictal periods.
    RESULTS: Compared to the background, we noted significant information flow (1) during the preictal period from the EZ to the baseline and hyperperfused regions, (2) during the ictal onset from the EZ to all three regions, and (3) during the period of seizure evolution from the area of hypoperfusion to all three regions.
    CONCLUSIONS: Hypoperfused brain regions were found to indirectly interact with the EZ during the ictal period.
    CONCLUSIONS: Our unique study, combining intracranial electrophysiology and perfusion imaging, presents compelling evidence of dynamic changes in directional connectivity between brain regions during the transition from interictal to ictal states.
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  • 文章类型: Journal Article
    (1)背景:在物流部门观察到的当前趋势是使用工业4.0工具来改善和提高货物装卸流程的效率。流行的解决方案之一是增强现实系统,该系统支持操作员的日常任务。本文旨在提出实施增强现实系统以支持仓库中的航空货运处理的设计假设。(2)方法:研究是基于五阶段分析程序进行的,旨在分析当前状态并确定实施AR系统的潜力。以下方法用于收集数据:共同参与者观察,过程分析,直接采访,分析内部文件,和适用的法律法规。(3)结果:所进行的研究允许识别伴随货物流的信息流,并开发一个项目来自动化选定的信息流。所获得的结果使得确定AR系统的实施将提高其有效性和效率的操作成为可能。(4)结论:获得的结果确定需要开发一种混合算法来安排仓库中的货物,并建立一个支持航空货物标记自我验证的系统。
    (1) Background: A current trend observed in the logistics sector is the use of Industry 4.0 tools to improve and enhance the efficiency of cargo handling processes. One of the popular solutions is an augmented reality system that supports operators in everyday tasks. The article aims to present design assumptions for implementing an augmented reality system to support air cargo handling at the warehouse. (2) Methods: Research was carried out based on a five-stage analytical procedure, aiming to analyze the current state and identify the potential for implementing the AR system. The following methods were used to collect data: co-participant observations, process analysis, direct interviews, analysis of internal documentation, and applicable legal regulations. (3) Results: The conducted research allowed for identifying information flows accompanying cargo flows and developing a project to automate selected information flows. The obtained results made it possible to identify operations for which the AR system\'s implementation will increase their effectiveness and efficiency. (4) Conclusions: The obtained results identified the need to develop a hybrid algorithm for arranging cargo in the warehouse and to build a system supporting self-verification of markings on air cargo.
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