scholarly journals Transmission delays and frequency detuning can regulate information flow between brain regions

2020 ◽  
Author(s):  
Aref Pariz ◽  
Ingo Fischer ◽  
Alireza Valizadeh ◽  
Claudio Mirasso
Keyword(s):  
Functional Connectivity ◽  
Information Transfer ◽  
Effective Connectivity ◽  
Signal Transmission ◽  
Brain Networks ◽  
Frequency Detuning ◽  
Brain Oscillations ◽  
Brain Areas ◽  
Neural Populations

AbstractBrain networks exhibit very variable and dynamical functional connectivity and flexible configurations of information exchange despite their overall fixed structure (connectome). Brain oscillations are hypothesized to underlie time-dependent functional connectivity by periodically changing the excitability of neural populations. In this paper, we investigate the role that the connection delay and the frequency detuning between different neural populations play in the transmission of signals. Based on numerical simulations and analytical arguments, we show that the amount of information transfer between two oscillating neural populations can be determined solely by their connection delay and the mismatch in their oscillation frequencies. Our results highlight the role of the collective phase response curve of the oscillating neural populations for the efficacy of signal transmission and the quality of the information transfer in brain networks.Author summaryCollective dynamics in brain networks is characterized by a coordinated activity of their constituent neurons that lead to brain oscillations. Many evidences highlight the role that brain oscillations play in signal transmission, the control of the effective communication between brain areas and the integration of information processed by different specialized regions. Oscillations periodically modulate the excitability of neurons and determine the response those areas receiving the signals. Based on the communication trough coherence (CTC) theory, the adjustment of the phase difference between local oscillations of connected areas can specify the timing of exchanged signals and therefore, the efficacy of the communication channels. An important factor is the delay in the transmission of signals from one region to another that affects the phase difference and timing, and consequently the impact of the signals. Despite this delay plays an essential role in CTC theory, its role has been mostly overlooked in previous studies. In this manuscript, we concentrate on the role that the connection delay and the oscillation frequency of the populations play in the signal transmission, and consequently in the effective connectivity, between two brain areas. Through extensive numerical simulations, as well as analytical results with reduced models, we show that these parameters have two essential impacts on the effective connectivity of the neural networks: First, that the populations advancing in phase to others do not necessarily play the role of the information source; and second, that the amount and direction of information transfer dependents on the oscillation frequency of the populations.

scholarly journals Transmission delays and frequency detuning can regulate information flow between brain regions

2021 ◽  
Vol 17 (4) ◽  
pp. e1008129
Author(s):  
Aref Pariz ◽  
Ingo Fischer ◽  
Alireza Valizadeh ◽  
Claudio Mirasso
Keyword(s):  
Functional Connectivity ◽  
Information Exchange ◽  
Information Transfer ◽  
Phase Response Curve ◽  
Signal Transmission ◽  
Brain Networks ◽  
Brain Regions ◽  
Transmission Delays ◽  
Neural Populations

Brain networks exhibit very variable and dynamical functional connectivity and flexible configurations of information exchange despite their overall fixed structure. Brain oscillations are hypothesized to underlie time-dependent functional connectivity by periodically changing the excitability of neural populations. In this paper, we investigate the role of the connection delay and the detuning between the natural frequencies of neural populations in the transmission of signals. Based on numerical simulations and analytical arguments, we show that the amount of information transfer between two oscillating neural populations could be determined by their connection delay and the mismatch in their oscillation frequencies. Our results highlight the role of the collective phase response curve of the oscillating neural populations for the efficacy of signal transmission and the quality of the information transfer in brain networks.

scholarly journals Intrinsic, dynamic and effective connectivity among large-scale brain networks modulated by oxytocin

2020 ◽  
Author(s):  
Xi Jiang ◽  
Xiaole Ma ◽  
Yayuan Geng ◽  
Zhiying Zhao ◽  
Feng Zhou ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Resting State ◽  
Emotional Processing ◽  
Large Scale ◽  
Effective Connectivity ◽  
Brain Networks ◽  
Emotional Behavior ◽  
Dependent Manner ◽  
Social Emotional ◽  
Using Data

AbstractThe neuropeptide oxytocin is a key modulator of social-emotional behavior and its intranasal administration can influence the functional connectivity of brain networks involved in the control of attention, emotion and reward reported in humans. However, no studies have systematically investigated the effects oxytocin on dynamic or directional aspects of functional connectivity. The present study employed a novel computational framework to investigate these latter aspects in 15 oxytocin-sensitive regions using data from randomized placebo-controlled between-subject resting state functional MRI studies incorporating 200 healthy subjects. Results showed that oxytocin extensively modulated effective connectivity both between and within emotion, reward, salience and social cognition processing networks and their interactions with the default mode network, but had no effect on the frequency of dynamic changes. Top-down control over emotional processing regions such as the amygdala was particularly affected. Oxytocin effects were also sex-dependent, being more extensive in males. Overall, these findings suggest that modulatory effects of oxytocin on both within- and between-network interactions may underlie its functional influence on social-emotional behaviors, although in a sex-dependent manner. Furthermore, they demonstrate a useful approach to determining pharmacological influences on resting state effective connectivity and support oxytocin’s potential therapeutic use in psychiatric disorders.

scholarly journals Disentangling functional connectivity effects of age and expertise in long-term meditators

2019 ◽  
Author(s):  
Roberto Guidotti ◽  
Cosimo Del Gratta ◽  
Mauro Gianni Perrucci ◽  
Gian Luca Romani ◽  
Antonino Raffone
Keyword(s):  
Functional Connectivity ◽  
Brain Networks ◽  
Focused Attention ◽  
Brain Areas ◽  
Age Related ◽  
Connectivity Patterns ◽  
Open Monitoring ◽  
Multivariate Pattern ◽  
Neurocognitive Decline

AbstractThe effects of intensive meditation practices on the functional and structural organization of the human brain have been addressed by a growing number of neuroscientific studies. However, the different modulations of meditation expertise and of ageing, in the underlying brain areas and networks, have not yet been fully elucidated. These effects should be distinguished in order to clarify how long-term meditation can modulate the connectivity between brain areas. To address this issue, we tested whether meditation expertise and age can be predicted from the multivariate pattern of functional Magnetic Resonance Imaging connectivity, in Theravada Buddhist monks with long-term practice in two different meditation forms: Focused Attention (FA) and Open Monitoring (OM).We found that functional connectivity patterns in both meditation forms can be used to predict expertise and age of long-term meditators. Our findings suggest that meditation expertise is associated with meditation-specific brain networks modulations, while age-related modifications are general and independent from the meditation type. Specifically, expertise modulated patterns during FA meditation include nodes and connections implicated in focusing, sustaining and monitoring attention, while the predictive patterns during OM meditation include nodes associated with cognitive and affective monitoring. Thus, the two forms of meditation may differentially contribute to counteract the effects of neurocognitive decline with ageing by neuroplasticity of brain networks.

scholarly journals Altered core networks of brain connectivity and personality traits in internet gaming disorder

2020 ◽  
Vol 9 (2) ◽  
pp. 298-311 ◽  
Author(s):  
Ji-Won Chun ◽  
Chang-Hyun Park ◽  
Jin-Young Kim ◽  
Jihye Choi ◽  
Hyun Cho ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Functional Connectivity ◽  
Personality Traits ◽  
Effective Connectivity ◽  
Brain Networks ◽  
Internet Gaming Disorder ◽  
Online Gaming ◽  
Gaming Disorder ◽  
Internet Gaming ◽  
Problematic Online Gaming

AbstractBackground and aimsAlthough the Internet has provided convenience and efficiency in many areas of everyday life, problems stemming from Internet use have also been identified, such as Internet gaming disorder (IGD). Internet addiction, which includes IGD, can be viewed as a behavioral addiction or impulse control disorder. This study investigated the altered functional and effective connectivity of the core brain networks in individuals with IGD compared to healthy controls (HCs).MethodsForty-five adults with IGD and 45 HCs were included in this study. To examine the brain networks related to personality traits that influence problematic online gaming, the left and right central executive network (CEN) and the salience network (SN) were included in the analysis. Also, to examine changes in major brain network topographies, we analyzed the default mode network (DMN).ResultsIGD participants showed lower functional connectivity between the dorsal lateral prefrontal cortex (DLPFC) and other regions in the CEN than HC participants during resting state. Also, IGD participants revealed reduced functional connectivity between the dorsal anterior cingulate cortex and other regions in the SN and lower functional connectivity in the medial prefrontal cortex of the anterior DMN. Notably, in IGD individuals but not HC individuals, there was a positive correlation between IGD severity and effective connectivity and a positive correlation between reward sensitivity and effective connectivity within the ventral striatum of the SN.ConclusionsProblematic online gaming was associated with neurofunctional alterations, impairing the capacity of core brain networks.

Functional connectivity reveals altered activation of distinct brain areas in pruritus of cholestasis

2018 ◽  
Vol 56 (01) ◽  
pp. E2-E89
Author(s):  
A Kremer ◽  
T Buchwald ◽  
M Vetter ◽  
A Dörfler ◽  
C Forster
Keyword(s):  
Functional Connectivity ◽  
Brain Areas

NATURAL SCIENTISTS AND RUSSIAN SCIENTIFIC FILMMAKING IN THE PRE-REVOLUTIONARY PERIOD (SCIENCE DIVISION OF THE A.A. KHANZHONKOV COMPANY)

2020 ◽  
Vol 42 (3) ◽  
pp. 355-368
Author(s):  
YEVGENIY ALEKSANDROV
Keyword(s):  
Information Transfer ◽  
Delayed Reaction ◽  
Russian Scientific ◽  
Physical Problems ◽  
Education Community ◽  
Future System ◽  
The Future ◽  
The Spectator ◽  
Revolutionary Period

The aim of the article is to recall the fi steps of comprehension by the scientific community of possibilities of a newly born means of the reality reflection. The means was initially oriented for obtaining reliable information and supposing a delayed reaction of the spectator in the process of communication. Recollection and understanding become more important under the distance education condition. Pre-revolutionary Russia lived anticipating changes, and the filmmaking was considered by the society as one of those progressive phenomena evidencing the coming of a new age. The scientists’ activity during the development of scientific fi in pre-revolutionary Russia was long hushed up and wasn’t considered as forming a basis for the future system of educational audio-visual communication. In this process there participated striking, creative personalities, mostly belonged to the community of Imperial Moscow University, which activity was during the age of changes. The significant contribution of pleiad of eminent scientists’ activity to the new direction formation was a reason to unify in one paper both their whole professional life data and information about their time-limited period of scientific fi In the future a more profound study of their achievements are considered to be promising. In the introduction the anterior period of the Russian fi appearance, where the scientific and education community of Russia was exploring the possibilities of a new means of information transfer for education purposes, is considered. Two main units are dedicated to the role of scientists in the development of scientific filmmaking for research and popularization of biomedical and physical problems.

Engaging regularly with fiction influences connectivity in cortical areas for language and mentalizing

2017 ◽  
Author(s):  
Roel M. Willems ◽  
Franziska Hartung
Keyword(s):  
Functional Connectivity ◽  
Time Course ◽  
Language Skills ◽  
Brain Regions ◽  
Brain Areas ◽  
Daily Lives ◽  
Cortical Areas ◽  
Social Abilities ◽  
Behavioral Evidence ◽  
Amount Of Reading

Behavioral evidence suggests that engaging with fiction is positively correlated with social abilities. The rationale behind this link is that engaging with fictional narratives offers a ‘training modus’ for mentalizing and empathizing. We investigated the influence of the amount of reading that participants report doing in their daily lives, on connections between brain areas while they listened to literary narratives. Participants (N=57) listened to two literary narratives while brain activation was measured with fMRI. We computed time-course correlations between brain regions, and compared the correlation values from listening to narratives to listening to reversed speech. The between-region correlations were then related to the amount of fiction that participants read in their daily lives. Our results show that amount of fiction reading is related to functional connectivity in areas known to be involved in language and mentalizing. This suggests that reading fiction influences social cognition as well as language skills.

scholarly journals Stoichiometric Analysis of Shifting in Subcellular Compartmentalization of HSP70 within Ischemic Penumbra

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3578
Author(s):  
Federica Mastroiacovo ◽  
Francesca Biagioni ◽  
Paola Lenzi ◽  
Larisa Ryskalin ◽  
Stefano Puglisi-Allegra ◽  
...  
Keyword(s):  
Direct Evidence ◽  
Neuronal Survival ◽  
Hsp 70 ◽  
Preclinical Models ◽  
Brain Areas ◽  
Cell Compartments ◽  
Control Brain ◽  
Disease Modifier ◽  
Subcellular Compartmentalization

The heat shock protein (HSP) 70 is considered the main hallmark in preclinical studies to stain the peri-infarct region defined area penumbra in preclinical models of brain ischemia. This protein is also considered as a potential disease modifier, which may improve the outcome of ischemic damage. In fact, the molecule HSP70 acts as a chaperonine being able to impact at several level the homeostasis of neurons. Despite being used routinely to stain area penumbra in light microscopy, the subcellular placement of this protein within area penumbra neurons, to our knowledge, remains undefined. This is key mostly when considering studies aimed at deciphering the functional role of this protein as a determinant of neuronal survival. The general subcellular placement of HSP70 was grossly reported in studies using confocal microscopy, although no direct visualization of this molecule at electron microscopy was carried out. The present study aims to provide a direct evidence of HSP70 within various subcellular compartments. In detail, by using ultrastructural morphometry to quantify HSP70 stoichiometrically detected by immuno-gold within specific organelles we could compare the compartmentalization of the molecule within area penumbra compared with control brain areas. The study indicates that two cell compartments in control conditions own a high density of HSP70, cytosolic vacuoles and mitochondria. In these organelles, HSP70 is present in amount exceeding several-fold the presence in the cytosol. Remarkably, within area penumbra a loss of such a specific polarization is documented. This leads to the depletion of HSP70 from mitochondria and mostly cell vacuoles. Such an effect is expected to lead to significant variations in the ability of HSP70 to exert its physiological roles. The present findings, beyond defining the neuronal compartmentalization of HSP70 within area penumbra may lead to a better comprehension of its beneficial/detrimental role in promoting neuronal survival.

scholarly journals Effect of corpus callosum agenesis on the language network in children and adolescents

2021 ◽  
Author(s):  
Lisa Bartha-Doering ◽  
Ernst Schwartz ◽  
Kathrin Kollndorfer ◽  
Florian Ph. S. Fischmeister ◽  
Astrid Novak ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Corpus Callosum ◽  
Network Connectivity ◽  
Functional Language ◽  
Healthy Controls ◽  
Language Abilities ◽  
Verbal Abilities ◽  
Left And Right ◽  
Language Network

AbstractThe present study is interested in the role of the corpus callosum in the development of the language network. We, therefore, investigated language abilities and the language network using task-based fMRI in three cases of complete agenesis of the corpus callosum (ACC), three cases of partial ACC and six controls. Although the children with complete ACC revealed impaired functions in specific language domains, no child with partial ACC showed a test score below average. As a group, ACC children performed significantly worse than healthy controls in verbal fluency and naming. Furthermore, whole-brain ROI-to-ROI connectivity analyses revealed reduced intrahemispheric and right intrahemispheric functional connectivity in ACC patients as compared to controls. In addition, stronger functional connectivity between left and right temporal areas was associated with better language abilities in the ACC group. In healthy controls, no association between language abilities and connectivity was found. Our results show that ACC is associated not only with less interhemispheric, but also with less right intrahemispheric language network connectivity in line with reduced verbal abilities. The present study, thus, supports the excitatory role of the corpus callosum in functional language network connectivity and language abilities.

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