scholarly journals Computation is concentrated in rich clubs of local cortical networks

2019 ◽  
Vol 3 (2) ◽  
pp. 384-404 ◽  
Author(s):  
Samantha P. Faber ◽  
Nicholas M. Timme ◽  
John M. Beggs ◽  
Ehren L. Newman
Keyword(s):  
Neural Circuits ◽  
Effective Connectivity ◽  
Neural Computation ◽  
Information Propagation ◽  
Cortical Circuits ◽  
Amount Of Information ◽  
Rich Club ◽  
The Rich ◽  
The Relationship ◽  
Do So

To understand how neural circuits process information, it is essential to identify the relationship between computation and circuit organization. Rich clubs, highly interconnected sets of neurons, are known to propagate a disproportionate amount of information within cortical circuits. Here, we test the hypothesis that rich clubs also perform a disproportionate amount of computation. To do so, we recorded the spiking activity of on average ∼300 well-isolated individual neurons from organotypic cortical cultures. We then constructed weighted, directed networks reflecting the effective connectivity between the neurons. For each neuron, we quantified the amount of computation it performed based on its inputs. We found that rich-club neurons compute ∼160% more information than neurons outside of the rich club. The amount of computation performed in the rich club was proportional to the amount of information propagation by the same neurons. This suggests that in these circuits, information propagation drives computation. In total, our findings indicate that rich-club organization in effective cortical circuits supports not only information propagation but also neural computation.

scholarly journals Computation is concentrated in rich clubs of local cortical neurons

2018 ◽  
Author(s):  
Samantha P. Faber ◽  
Nicholas M. Timme ◽  
John M. Beggs ◽  
Ehren L. Newman
Keyword(s):  
Cortical Neurons ◽  
Effective Connectivity ◽  
Neural Computation ◽  
Information Propagation ◽  
Cortical Circuits ◽  
Amount Of Information ◽  
Rich Club ◽  
The Rich ◽  
Do So ◽  
Spiking Activity

ABSTRACTTo understand how neural circuits process information, it is essential to identify the relationship between computation and circuit topology. Rich-clubs, highly interconnected sets of neurons, are known to propagate a disproportionate amount of information within cortical circuits. Here, we test the hypothesis that rich-clubs also perform a disproportionate amount of computation. To do so, we recorded the spiking activity of on average ∼300 well-isolated individual neurons from organotypic cortical cultures. We then constructed weighted, directed networks reflecting the effective connectivity between the neurons. For each neuron, we quantified the amount of computation it performed based on its inputs. We found that rich-club neurons compute ∼200% more information than neurons outside of the rich club. Indeed, the amount of computation performed in the rich-club was proportional to the amount information propagation by the same neurons. This suggests that, in these circuits, information propagation drives computation. Comparing the computation-to-propagation ratio inside versus outside of the rich club showed that rich clubs compute at a slightly, though significantly, reduced level (∼4% lower). In total, our findings indicate that rich club topology in effective cortical circuits supports not only information propagation but also neural computation.AUTHOR SUMMARYHere we answer the question of whether rich club topology in functional cortical circuits supports neural computation as it has been previously shown to do for information propagation. To do so, we combined network analysis with information theoretic tools to analyze the spiking activity of hundreds of neurons recorded from organotypic cultures of mouse somatosensory cortex. We found that neurons in rich clubs computed significantly more than neurons outside of rich clubs, suggesting that rich-clubs do support computation in cortical circuits. Indeed, the amount of computation that we found in the rich club was proportional to the amount of information they propagate suggesting that, in these circuits, information propagation drives computation.

scholarly journals Task-related effective connectivity reveals that the cortical rich club gates cortex-wide communication

2017 ◽  
Author(s):  
Mario Senden ◽  
Niels Reuter ◽  
Martijn P. van den Heuvel ◽  
Rainer Goebel ◽  
Gustavo Deco ◽  
...  
Keyword(s):  
Information Exchange ◽  
Effective Connectivity ◽  
Functional Integration ◽  
Brain Regions ◽  
Rich Club ◽  
State Dependent ◽  
Gating Mechanism ◽  
The Rich ◽  
Cortical Regions ◽  
Peripheral Regions

AbstractHigher cognition may require the globally coordinated integration of specialized brain regions into functional networks. A collection of structural cortical hubs - referred to as the rich club - has been hypothesized to support task-specific functional integration. In the present paper, we use a whole-cortex model to estimate directed interactions between 68 cortical regions from fMRI activity for four different tasks (reflecting different cognitive domains) and resting state. We analyze the state-dependent input and output effective connectivity of the structural rich club and relate these to whole-cortex dynamics and network reconfigurations. We find that the cortical rich club exhibits an increase in outgoing effective connectivity during task performance as compared to rest while incoming connectivity remains constant. Increased outgoing connectivity targets a sparse set of peripheral regions with specific regions strongly overlapping between tasks. At the same time, community detection analyses reveal massive reorganizations of interactions among peripheral regions, including those serving as target of increased rich club output. This suggests that while peripheral regions may play a role in several tasks, their concrete interplay might nonetheless be task-specific. Furthermore, we observe that whole-cortex dynamics are faster during task as compared to rest. The decoupling effects usually accompanying faster dynamics appear to be counteracted by the increased rich club outgoing effective connectivity. Together our findings speak to a gating mechanism of the rich club that supports fast-paced information exchange among relevant peripheral regions in a task-specific and goal-directed fashion, while constantly listening to the whole network.

scholarly journals Motives to Assist and Reasons to Assist: the Case of Global Poverty

2020 ◽  
Author(s):  
Simon Keller
Keyword(s):  
Marked Effect ◽  
Global Poverty ◽  
The Poor ◽  
The Rich ◽  
The Relationship ◽  
Do So

The principle of assistance says that the global rich should help the global poor because they are able to do so, and at little cost. The principle of contribution says that the rich should help the poor because the rich are partly to blame for the plight of the poor. this paper explores the relationship between the two principles and offers support for one version of the principle of assistance. The principle of assistance is most plausible, the paper argues, when formulated so as to identify obligations that arise from the needs of particular identifiable members of the global poor, not from impersonal rules or values. Under that formulation, the principle can explain why knowledge of the circumstances faced by individual members of the global poor can have such a marked effect upon the willingness of the global rich to provide help, and can offer a better grounded motivational basis for helping the global poor. These are real advantages, the paper argues, and ones that cannot be matched by stories that focus upon the ways in which the global rich contribute to global poverty.<br>

scholarly journals Motives to Assist and Reasons to Assist: the Case of Global Poverty

2020 ◽  
Author(s):  
Simon Keller
Keyword(s):  
Marked Effect ◽  
Global Poverty ◽  
The Poor ◽  
The Rich ◽  
The Relationship ◽  
Do So

The principle of assistance says that the global rich should help the global poor because they are able to do so, and at little cost. The principle of contribution says that the rich should help the poor because the rich are partly to blame for the plight of the poor. this paper explores the relationship between the two principles and offers support for one version of the principle of assistance. The principle of assistance is most plausible, the paper argues, when formulated so as to identify obligations that arise from the needs of particular identifiable members of the global poor, not from impersonal rules or values. Under that formulation, the principle can explain why knowledge of the circumstances faced by individual members of the global poor can have such a marked effect upon the willingness of the global rich to provide help, and can offer a better grounded motivational basis for helping the global poor. These are real advantages, the paper argues, and ones that cannot be matched by stories that focus upon the ways in which the global rich contribute to global poverty.<br>

America's Lone Star Constitution

2018 ◽  
Author(s):  
Lucas A. Powe Jr.
Keyword(s):  
Supreme Court ◽  
Capital Punishment ◽  
School Finance ◽  
Constitutional Law ◽  
Civil Liberty ◽  
Voting Rights ◽  
The Rich ◽  
The Relationship

Texas has created more constitutional law than any other state. In any classroom nationwide, any basic constitutional law course can be taught using nothing but Texas cases. That, however, understates the history and politics behind the cases. Beyond representing all doctrinal areas of constitutional law, Texas cases deal with the major issues of the nation. This book charts the rich and pervasive development of Texas-inspired constitutional law. From voting rights to railroad regulations, school finance to capital punishment, poverty to civil liberty, this book provides a window into the relationship between constitutional litigation and ordinary politics at the Texas Supreme Court, illuminating how all of the fiercest national divides over what the Constitution means took shape in Texas.

Home, Sweet Home: Negotiating Intimacy in Brazilian Elitist Closed Condominiums

2020 ◽  
Vol 9 (1) ◽  
pp. 374-395
Author(s):  
Rafael Ignacio Estrada Mejia ◽  
Carla Guerrón Guerron Montero
Keyword(s):  
Collective Mode ◽  
Living Arrangement ◽  
Public Life ◽  
Ethnographic Research ◽  
Social Distinction ◽  
History Of ◽  
Collective Production ◽  
The Relationship ◽  
Do So

This article aims to decrease the cultural invisibility of the wealthy by exploring the Brazilian emergent elites and their preferred living arrangement: elitist closed condominiums (BECCs) from a micropolitical perspective.  We answer the question: What is the relationship between intimacy and subjectivity that is produced in the collective mode of existence of BECCs? To do so, we trace the history of the elite home, from the master’s house (casa grande) to contemporary closed condominiums. Following, we discuss the features of closed condominiums as spaces of segregation, fragmentation and social distinction, characterized by minimal public life and an internalized sociability. Finally, based on ethnographic research conducted in the mid-size city of Londrina (state of Paraná) between 2015 and 2017, we concentrate on four members of the emergent elite who live in BECCs, addressing their collective production of subjectivity. 

The Role of the Judiciary and Its Relationship to the Convention on the Rights of Persons with Disabilities

2018 ◽  
Author(s):  
Lisa Waddington
Keyword(s):  
Legal System ◽  
Amicus Curiae ◽  
Persons With Disabilities ◽  
Legal Duty ◽  
The Relationship ◽  
Do So

This chapter examines the role of the judiciary with regard to the Convention on the Rights of Persons with Disabilities (CRPD). It considers the relationship which the judiciary have or appear to perceive themselves as having with the CRPD and explores some of the factors seemingly prompting courts to refer to it. The first section reflects on: whether judges are able to choose to refer to the Convention or have a legal duty to do so; the significance of the fact that the CRPD is international law; and whether judges appear to see themselves merely as domestic actors, or as agents or trustees of the CRPD. The second section explores whether judges are referring to the CRPD in response to arguments raised before the court or doing so of their own volition. Also considered are the relevance of amicus curiae interventions; reasons for referral related to the domestic legal system; and the role of particularly engaged individuals.

Protecting Natural Resources

2018 ◽  
Author(s):  
Jérémie Gilbert
Keyword(s):  
Climate Change ◽  
Human Rights ◽  
Natural Resources ◽  
Environmental Law ◽  
Legal Framework ◽  
Human Rights Law ◽  
International Environmental Law ◽  
Conservation Of Natural Resources ◽  
The Relationship ◽  
Do So

This chapter focuses on the connection between the international legal framework governing the conservation of natural resources and human rights law. The objective is to examine the potential synergies between international environmental law and human rights when it comes to the protection of natural resources. To do so, it concentrates on three main areas of potential convergence. It first focuses on the pollution of natural resources and analyses how human rights law offers a potential platform to seek remedies for the victims of pollution. It next concentrates on the conservation of natural resources, particularly on the interconnection between protected areas, biodiversity, and human rights law. Finally, it examines the relationship between climate change and human rights law, focusing on the role that human rights law can play in the development of the current climate change adaptation and mitigation frameworks.

scholarly journals On the Role of Bilateral Brain Hypofunction and Abnormal Lateralization of Cortical Information Flow as Neural Underpinnings of Conventional Metaphor Processing Impairment in Schizophrenia: An fMRI and EEG Study

2021 ◽  
Author(s):  
Przemysław Adamczyk ◽  
Martin Jáni ◽  
Tomasz S. Ligeza ◽  
Olga Płonka ◽  
Piotr Błądziński ◽  
...  
Keyword(s):  
Information Flow ◽  
Language Processing ◽  
Time Course ◽  
Figurative Language ◽  
Neural Circuits ◽  
Effective Connectivity ◽  
Brain Regions ◽  
Blood Oxygenation ◽  
Control Group ◽  
Metaphor Processing

AbstractFigurative language processing (e.g. metaphors) is commonly impaired in schizophrenia. In the present study, we investigated the neural activity and propagation of information within neural circuits related to the figurative speech, as a neural substrate of impaired conventional metaphor processing in schizophrenia. The study included 30 schizophrenia outpatients and 30 healthy controls, all of whom were assessed with a functional Magnetic Resonance Imaging (fMRI) and electroencephalography (EEG) punchline-based metaphor comprehension task including literal (neutral), figurative (metaphorical) and nonsense (absurd) endings. The blood oxygenation level-dependent signal was recorded with 3T MRI scanner and direction and strength of cortical information flow in the time course of task processing was estimated with a 64-channel EEG input for directed transfer function. The presented results revealed that the behavioral manifestation of impaired figurative language in schizophrenia is related to the hypofunction in the bilateral fronto-temporo-parietal brain regions (fMRI) and various differences in effective connectivity in the fronto-temporo-parietal circuit (EEG). Schizophrenia outpatients showed an abnormal pattern of connectivity during metaphor processing which was related to bilateral (but more pronounced at the left hemisphere) hypoactivation of the brain. Moreover, we found reversed lateralization patterns, i.e. a rightward-shifted pattern during metaphor processing in schizophrenia compared to the control group. In conclusion, the presented findings revealed that the impairment of the conventional metaphor processing in schizophrenia is related to the bilateral brain hypofunction, which supports the evidence on reversed lateralization of the language neural network and the existence of compensatory recruitment of alternative neural circuits in schizophrenia.

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