scholarly journals Uniform Pooling for Graph Networks

2020 ◽  
Vol 10 (18) ◽  
pp. 6287
Author(s):  
Jian Qin ◽  
Li Liu ◽  
Hui Shen ◽  
Dewen Hu
Keyword(s):  
High Efficiency ◽  
Brain Connectivity ◽  
Graph Embedding ◽  
Point Of View ◽  
Graph Classification ◽  
Improve Performance ◽  
Classification Tasks ◽  
Multiple Graph ◽  
The Brain ◽  
Protein Graphs

The graph convolution network has received a lot of attention because it extends the convolution to non-Euclidean domains. However, the graph pooling method is still less concerned, which can learn coarse graph embedding to facilitate graph classification. Previous pooling methods were based on assigning a score to each node and then pooling only the highest-scoring nodes, which might throw away whole neighbourhoods of nodes and therefore information. Here, we proposed a novel pooling method UGPool with a new point-of-view on selecting nodes. UGPool learns node scores based on node features and uniformly pools neighboring nodes instead of top nodes in the score-space, resulting in a uniformly coarsened graph. In multiple graph classification tasks, including the protein graphs, the biological graphs and the brain connectivity graphs, we demonstrated that UGPool outperforms other graph pooling methods while maintaining high efficiency. Moreover, we also show that UGPool can be integrated with multiple graph convolution networks to effectively improve performance compared to no pooling.

Permutation Disalignment Index as an Indirect, EEG-Based, Measure of Brain Connectivity in MCI and AD Patients

2017 ◽  
Vol 27 (05) ◽  
pp. 1750020 ◽  
Author(s):  
Nadia Mammone ◽  
Lilla Bonanno ◽  
Simona De Salvo ◽  
Silvia Marino ◽  
Placido Bramanti ◽  
...  
Keyword(s):  
Coupling Strength ◽  
Brain Connectivity ◽  
Point Of View ◽  
Eeg Signals ◽  
Dissimilarity Index ◽  
Delta Band ◽  
Prodromal Ad ◽  
The Brain ◽  
Variability Study ◽  
Robust To Noise

Objective: In this work, we introduce Permutation Disalignment Index (PDI) as a novel nonlinear, amplitude independent, robust to noise metric of coupling strength between time series, with the aim of applying it to electroencephalographic (EEG) signals recorded longitudinally from Alzheimer’s Disease (AD) and Mild Cognitive Impaired (MCI) patients. The goal is to indirectly estimate the connectivity between the cortical areas, through the quantification of the coupling strength between the corresponding EEG signals, in order to find a possible matching with the disease’s progression. Method: PDI is first defined and tested on simulated interacting dynamic systems. PDI is then applied to real EEG recorded from 8 amnestic MCI subjects and 7 AD patients, who were longitudinally evaluated at time [Formula: see text]0 and 3 months later (time [Formula: see text]1). At time [Formula: see text]1, 5 out of 8 MCI patients were still diagnosed MCI (stable MCI) whereas the remaining 3 exhibited a conversion from MCI to AD (prodromal AD). PDI was compared to the Spectral Coherence and the Dissimilarity Index. Results: Limited to the size of the analyzed dataset, both Coherence and PDI resulted sensitive to the conversion from MCI to AD, even though only PDI resulted specific. In particular, the intrasubject variability study showed that the three patients who converted to AD exhibited a significantly ([Formula: see text]) increased PDI (reduced coupling strength) in delta and theta bands. As regards Coherence, even though it significantly decreased in the three converted patients, in delta and theta bands, such a behavior was also detectable in one stable MCI patient, in delta band, thus making Coherence not specific. From the Dissimilarity Index point of view, the converted MCI showed no peculiar behavior. Conclusions: PDI significantly increased, in delta and theta bands, specifically in the MCI subjects who converted to AD. The increase of PDI reflects a reduced coupling strength among the brain areas, which is consistent with the expected connectivity reduction associated to AD progression.

DIRECTIONS OF ASSOCIATIVE IDENTIFICATION OF PERSONAL NAMES

2019 ◽  
Vol 18 (28) ◽  
pp. 118-128
Author(s):  
Olena Karpenko ◽  
Tetiana Stoianova
Keyword(s):  
Proper Names ◽  
Mental Lexicon ◽  
Point Of View ◽  
Sound Symbolism ◽  
Personal Names ◽  
Communicative Process ◽  
Proper Name ◽  
Definition Of ◽  
Scientific Value ◽  
The Brain

The article is devoted to the study of personal names from a cognitive point of view. The study is based on the cognitive concept that speech actually exists not in the speech, not in linguistic writings and dictionaries, but in consciousness, in the mental lexicon, in the language of the brain. The conditions for identifying personal names can encompass not only the context, encyclopedias, and reference books, but also the sound form of the word. In the communicative process, during a free associative experiment, which included a name and a recipient’s mental lexicon. The recipient was assigned a task to quickly give some association to the name. The aggregate of a certain number of reactions of different recipients forms the associative field of a proper name. The associative experiment creates the best conditions for identifying the lexeme. The definition of a monosemantic personal name primarily includes the search of what it denotes, while during the process of identifying a polysemantic personal name recipients tend have different reactions. Scientific value is posed by the effect of the choice of letters for the name, sound symbolism, etc. The following belong to the generalized forms of identification: usage of a hyperonym; synonyms and periphrases or simple descriptions; associations denoting the whole (name stimulus) by reference to its part (associatives); cognitive structures such as “stimulus — association” and “whole (stimulus) — part (associative)”; lack of adjacency; mysterious associations. The topicality of the study is determined by its perspective to identify the directions of associative identification of proper names, which is one of the branches of cognitive onomastics. The purpose of the study is to identify, review, and highlight the directions of associative identification of proper names; the object of the research is the names in their entirety and variety; its subject is the existence of names in the mental lexicon, which determines the need for singling out the directions for the associative identification of the personal names.

Subjectivity as a sentient perspective and the role of interoception

2018 ◽  
Author(s):  
Helena De Preester
Keyword(s):  
Crucial Role ◽  
Point Of View ◽  
Basic Form ◽  
Bodily States ◽  
The Brain ◽  
Phenomenological Point

This chapter argues that the most basic form of subjectivity is different from and more fundamental than having a self, and forwards a hypothesis about the origin of subjectivity in terms of interoception. None of those topics are new, and a consensus concerning the homeostatic-interoceptive origin of subjectivity is rapidly growing in the domains of the neurosciences and psychology. This chapter critically explores that growing consensus, and it argues that the idea that the brain topographically represents bodily states is unfit for thinking about the coming about of subjectivity. In the first part, four inherent characteristics of subjectivity are discussed from a philosophical phenomenological point of view. The second part explores whether a model of subjectivity in which interoception maintains its crucial role is possible without relying on topographical representations of the in-depth body, and giving due to the inherent characteristics of subjectivity.

scholarly journals Multifunctional Cantilevers as Working Elements in Solid-State Cooling Devices

Actuators ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 58
Author(s):  
Andraž Bradeško ◽  
Lovro Fulanović ◽  
Marko Vrabelj ◽  
Aleksander Matavž ◽  
Mojca Otoničar ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Ethylene Glycol ◽  
Contact Resistance ◽  
High Efficiency ◽  
Thermal Contact ◽  
Point Of View ◽  
Practical Implementation ◽  
Cooling Devices ◽  
Cascade Structure ◽  
Lead Magnesium

Despite the challenges of practical implementation, electrocaloric (EC) cooling remains a promising technology because of its good scalability and high efficiency. Here, we investigate the feasibility of an EC cooling device that couples the EC and electromechanical (EM) responses of a highly functionally, efficient, lead magnesium niobate ceramic material. We fabricated multifunctional cantilevers from this material and characterized their electrical, EM and EC properties. Two active cantilevers were stacked in a cascade structure, forming a proof-of-concept device, which was then analyzed in detail. The cooling effect was lower than the EC effect of the material itself, mainly due to the poor solid-to-solid heat transfer. However, we show that the use of ethylene glycol in the thermal contact area can significantly reduce the contact resistance, thereby improving the heat transfer. Although this solution is most likely impractical from the design point of view, the results clearly show that in this and similar cooling devices, a non-destructive, surface-modification method, with the same effectiveness as that of ethylene glycol, will have to be developed to reduce the thermal contact resistance. We hope this study will motivate the further development of multifunctional cooling devices.

scholarly journals The Modular Organization of Pain Brain Networks: An fMRI Graph Analysis Informed by Intracranial EEG

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Camille Fauchon ◽  
David Meunier ◽  
Isabelle Faillenot ◽  
Florence B Pomares ◽  
Hélène Bastuji ◽  
...  
Keyword(s):  
Information Integration ◽  
Functional Organization ◽  
Brain Connectivity ◽  
Brain Networks ◽  
Modular Organization ◽  
Noxious Heat ◽  
Intracranial Eeg ◽  
Brain Connectome ◽  
Posterior Parietal ◽  
The Brain

Abstract Intracranial EEG (iEEG) studies have suggested that the conscious perception of pain builds up from successive contributions of brain networks in less than 1 s. However, the functional organization of cortico-subcortical connections at the multisecond time scale, and its accordance with iEEG models, remains unknown. Here, we used graph theory with modular analysis of fMRI data from 60 healthy participants experiencing noxious heat stimuli, of whom 36 also received audio stimulation. Brain connectivity during pain was organized in four modules matching those identified through iEEG, namely: 1) sensorimotor (SM), 2) medial fronto-cingulo-parietal (default mode-like), 3) posterior parietal-latero-frontal (central executive-like), and 4) amygdalo-hippocampal (limbic). Intrinsic overlaps existed between the pain and audio conditions in high-order areas, but also pain-specific higher small-worldness and connectivity within the sensorimotor module. Neocortical modules were interrelated via “connector hubs” in dorsolateral frontal, posterior parietal, and anterior insular cortices, the antero-insular connector being most predominant during pain. These findings provide a mechanistic picture of the brain networks architecture and support fractal-like similarities between the micro-and macrotemporal dynamics associated with pain. The anterior insula appears to play an essential role in information integration, possibly by determining priorities for the processing of information and subsequent entrance into other points of the brain connectome.

scholarly journals A novel dephosphorylation targeting chimera selectively promoting tau removal in tauopathies

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Jie Zheng ◽  
Na Tian ◽  
Fei Liu ◽  
Yidian Zhang ◽  
Jingfen Su ◽  
...  
Keyword(s):  
Neurodegenerative Disorders ◽  
Protein Phosphatase ◽  
High Efficiency ◽  
Microtubule Assembly ◽  
Hyperphosphorylated Tau ◽  
Phosphatase 2A ◽  
Dependent Learning ◽  
The Brain

AbstractIntraneuronal accumulation of hyperphosphorylated tau is a hallmark pathology shown in over twenty neurodegenerative disorders, collectively termed as tauopathies, including the most common Alzheimer’s disease (AD). Therefore, selectively removing or reducing hyperphosphorylated tau is promising for therapies of AD and other tauopathies. Here, we designed and synthesized a novel DEPhosphorylation TArgeting Chimera (DEPTAC) to specifically facilitate the binding of tau to Bα-subunit-containing protein phosphatase 2A (PP2A-Bα), the most active tau phosphatase in the brain. The DEPTAC exhibited high efficiency in dephosphorylating tau at multiple AD-associated sites and preventing tau accumulation both in vitro and in vivo. Further studies revealed that DEPTAC significantly improved microtubule assembly, neurite plasticity, and hippocampus-dependent learning and memory in transgenic mice with inducible overexpression of truncated and neurotoxic human tau N368. Our data provide a strategy for selective removal of the hyperphosphorylated tau, which sheds new light for the targeted therapy of AD and related-tauopathies.

Information-based decoding of the coupling among human brain activity and movement paths

2021 ◽  
pp. 1-10
Author(s):  
Shahul Mujib Kamal ◽  
Norazryana Mat Dawi ◽  
Hamidreza Namazi
Keyword(s):  
Brain Activity ◽  
Point Of View ◽  
Physiological Signals ◽  
Human Walking ◽  
Eeg Signals ◽  
Rehabilitation Science ◽  
Information Contents ◽  
First Time ◽  
The Brain ◽  
Brain Reaction

BACKGROUND: Walking like many other actions of a human is controlled by the brain through the nervous system. In fact, if a problem occurs in our brain, we cannot walk correctly. Therefore, the analysis of the coupling of brain activity and walking is very important especially in rehabilitation science. The complexity of movement paths is one of the factors that affect human walking. For instance, if we walk on a path that is more complex, our brain activity increases to adjust our movements. OBJECTIVE: This study for the first time analyzed the coupling of walking paths and brain reaction from the information point of view. METHODS: We analyzed the Shannon entropy for electroencephalography (EEG) signals versus the walking paths in order to relate their information contents. RESULTS: According to the results, walking on a path that contains more information causes more information in EEG signals. A strong correlation (p= 0.9999) was observed between the information contents of EEG signals and walking paths. Our method of analysis can also be used to investigate the relation among other physiological signals of a human and walking paths, which has great benefits in rehabilitation science.

scholarly journals The Brain Connectivity Basis of Semantic Dementia: A Selective Review

2015 ◽  
Vol 21 (10) ◽  
pp. 784-792 ◽  
Author(s):  
Qing Yang ◽  
Qi-Hao Guo ◽  
Yan-Chao Bi
Keyword(s):  
Brain Connectivity ◽  
Semantic Dementia ◽  
Selective Review ◽  
The Brain

Еnactivist Criticism of the Neurobiological Theory of Consciousness

2021 ◽  
pp. 76-80
Author(s):  
Anastasia O. Shabalina ◽  
Keyword(s):  
Philosophy Of Mind ◽  
Point Of View ◽  
Science Methods ◽  
Neural Processes ◽  
Neural Substrate ◽  
Critical Revision ◽  
Concept Of Information ◽  
The Mind ◽  
The Brain ◽  
Person Experience

The article considers the main arguments against the neurobiological theory of consciousness from the point of view of the enactivist approach within the philosophy of mind. The neurobiological theory of consciousness, which reduces consciousness to neural activity, is currently the dominant approach to the mind-body problem. The neurobiological theory emerged as a result of advances in research on the phenomena of consciousness and through the development of technologies for visualizing the internal processes of mind. However, at the very heart of this theory, there is a number of logical contradictions. The non-reductive enactivist approach to consciousness, introduced in this article, contributes to the existing argumentation against the reduction of consciousness to neural processes with remonstrations that take into account the modern neuroscientific data. The article analyzes the argumentation of the sensorimotor enactivism developed by A. Noe and offers the account of the teleosemantic approach to the concept of information provided by R. Cao. The key problems of the neurobiological theory of consciousness are highlighted, and the objections emerging within the framework of the enactivist approach are analyzed. Since the main concepts on which the neural theory is based are the concepts of neural substrate, cognition as representation, and information as a unit of cognition, the author of the article presents three key enactivist ideas that oppose them. First, the enactivist concept of cognition as action allows us to consider the first-person experience as a mode of action, and not as a state of the brain substrate. Second, the article deals with the “explanatory externalism” argument proposed by Noe, who refutes the image of cognition as a representation in the brain. Finally, in order to critically revise the concept of information as a unit of cognition, the author analyzes Cao’s idea, which represents a teleosemantic approach, but is in line with the general enactivist argumentation. Cao shows that the application of the concept “information” to neural processes is problematic: no naturalized information is found in the brain as a physical substrate. A critical revision of beliefs associated with the neural theory of consciousness leads us to recognize that there are not enough grounds for reducing consciousness to processes that take place in the brain. That is why Noe calls expectations that the visualization of processes taking place in the brain with the help of the modern equipment will be able to depict the experience of consciousness the “new phrenology”, thus indicating the naive character of neural reduction. The article concludes that natural science methods are insufficient for the study of consciousness.

scholarly journals Category representations in the brain are both discretely localized and widely distributed

2018 ◽  
Vol 119 (6) ◽  
pp. 2256-2264 ◽  
Author(s):  
Zarrar Shehzad ◽  
Gregory McCarthy
Keyword(s):  
Functional Mri ◽  
Brain Connectivity ◽  
Strong Support ◽  
Brain Regions ◽  
Distributed Representations ◽  
Domain Specific ◽  
Category Information ◽  
Shared Information ◽  
Unique Domain ◽  
The Brain

Whether category information is discretely localized or represented widely in the brain remains a contentious issue. Initial functional MRI studies supported the localizationist perspective that category information is represented in discrete brain regions. More recent fMRI studies using machine learning pattern classification techniques provide evidence for widespread distributed representations. However, these latter studies have not typically accounted for shared information. Here, we find strong support for distributed representations when brain regions are considered separately. However, localized representations are revealed by using analytical methods that separate unique from shared information among brain regions. The distributed nature of shared information and the localized nature of unique information suggest that brain connectivity may encourage spreading of information but category-specific computations are carried out in distinct domain-specific regions. NEW & NOTEWORTHY Whether visual category information is localized in unique domain-specific brain regions or distributed in many domain-general brain regions is hotly contested. We resolve this debate by using multivariate analyses to parse functional MRI signals from different brain regions into unique and shared variance. Our findings support elements of both models and show information is initially localized and then shared among other regions leading to distributed representations being observed.

Sign in / Sign up

Export Citation Format

Share Document