Brain Asymmetry: Towards an Asymmetrical Neurovisceral Integration

Despite the ancestral evidence of an asymmetry in motor predominance, going through the inspiring discoveries of Broca and Wernicke on the localization of language processing, continuing with the subsequent noise coinciding with the study of brain function in commissurotomized patients—and the subsequent avalanche of data on the asymmetric distribution of multiple types of neurotransmitters in physiological and pathological conditions—even today, the functional significance of brain asymmetry is still unknown. Currently, multiple evidence suggests that functional asymmetries must have a neurochemical substrate and that brain asymmetry is not a static concept but rather a dynamic one, with intra- and inter-hemispheric interactions between its various processes, and that it is modifiable depending on changing endogenous and environmental conditions. Furthermore, based on the concept of neurovisceral integration in the overall functioning of an organism, some evidence has emerged suggesting that this integration could be organized asymmetrically, using the autonomic nervous system as a bidirectional communication pathway, whose performance would also be asymmetric. However, the functional significance of this distribution, as well as the evolutionary advantage of an asymmetric nervous organization, is still unknown.

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Language and Aging

The Oxford Handbook of Neurolinguistics ◽

10.1093/oxfordhb/9780190672027.013.12 ◽

2019 ◽

pp. 294-316

Author(s):

Jonathan E. Peelle

Keyword(s):

Language Processing ◽

Brain Function ◽

Neural Systems ◽

Language Abilities ◽

Physiological Mechanisms ◽

Cognitive Changes ◽

Older Adulthood ◽

Neural Organization ◽

Age Related ◽

High Level

Language processing in older adulthood is a model of balance between preservation and decline. Despite widespread changes to physiological mechanisms supporting perception and cognition, older adults’ language abilities are frequently well preserved. At the same time, the neural systems engaged to achieve this high level of success change, and individual differences in neural organization appear to differentiate between more and less successful performers. This chapter reviews anatomical and cognitive changes that occur in aging and popular frameworks for age-related changes in brain function, followed by an examination of how these principles play out in the context of language comprehension and production.

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A Fast Transform for Brain Connectivity Difference Evaluation

Neuroinformatics ◽

10.1007/s12021-021-09518-7 ◽

2021 ◽

Author(s):

Massimiliano Zanin ◽

Ilinka Ivanoska ◽

Bahar Güntekin ◽

Görsev Yener ◽

Tatjana Loncar-Turukalo ◽

...

Keyword(s):

Brain Function ◽

Functional Significance ◽

Brain Connectivity ◽

Network Reconstruction ◽

Auxiliary Space ◽

Fast Transform

AbstractAnatomical and dynamical connectivity are essential to healthy brain function. However, quantifying variations in connectivity across conditions or between patient populations and appraising their functional significance are highly non-trivial tasks. Here we show that link ranking differences induce specific geometries in a convenient auxiliary space that are often easily recognisable at mere eye inspection. Link ranking can also provide fast and reliable criteria for network reconstruction parameters for which no theoretical guideline has been proposed.

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Gut–brain axis biochemical signalling from the gastrointestinal tract to the central nervous system: gut dysbiosis and altered brain function

Postgraduate Medical Journal ◽

10.1136/postgradmedj-2017-135424 ◽

2018 ◽

Vol 94 (1114) ◽

pp. 446-452 ◽

Cited By ~ 16

Author(s):

Borros M Arneth

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Brain Function ◽

Well Being ◽

Immune System Activation ◽

Published Evidence ◽

Bidirectional Communication ◽

The Central Nervous System ◽

Intestinal Functions ◽

The Brain

BackgroundThe gut–brain axis facilitates a critical bidirectional link and communication between the brain and the gut. Recent studies have highlighted the significance of interactions in the gut–brain axis, with a particular focus on intestinal functions, the nervous system and the brain. Furthermore, researchers have examined the effects of the gut microbiome on mental health and psychiatric well-being.The present study reviewed published evidence to explore the concept of the gut–brain axis.AimsThis systematic review investigated the relationship between human brain function and the gut–brain axis.MethodsTo achieve these objectives, peer-reviewed articles on the gut–brain axis were identified in various electronic databases, including PubMed, MEDLINE, CIHAHL, Web of Science and PsycINFO.ResultsData obtained from previous studies showed that the gut–brain axis links various peripheral intestinal functions to brain centres through a broad range of processes and pathways, such as endocrine signalling and immune system activation. Researchers have found that the vagus nerve drives bidirectional communication between the various systems in the gut–brain axis. In humans, the signals are transmitted from the liminal environment to the central nervous system.ConclusionsThe communication that occurs in the gut–brain axis can alter brain function and trigger various psychiatric conditions, such as schizophrenia and depression. Thus, elucidation of the gut–brain axis is critical for the management of certain psychiatric and mental disorders.

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Searching through functional space reveals distributed visual, auditory, and semantic coding in the human brain

10.1101/2020.04.20.052175 ◽

2020 ◽

Author(s):

Sreejan Kumar ◽

Cameron T. Ellis ◽

Thomas O’Connell ◽

Marvin M Chun ◽

Nicholas B. Turk-Browne

Keyword(s):

Human Brain ◽

Language Processing ◽

Brain Function ◽

Computational Models ◽

Brain Activity ◽

Functional Space ◽

Semantic Features ◽

Brain Functions ◽

Auditory Features ◽

The Brain

AbstractThe extent to which brain functions are localized or distributed is a foundational question in neuroscience. In the human brain, common fMRI methods such as cluster correction, atlas parcellation, and anatomical searchlight are biased by design toward finding localized representations. Here we introduce the functional searchlight approach as an alternative to anatomical searchlight analysis, the most commonly used exploratory multivariate fMRI technique. Functional searchlight removes any anatomical bias by grouping voxels based only on functional similarity and ignoring anatomical proximity. We report evidence that visual and auditory features from deep neural networks and semantic features from a natural language processing model are more widely distributed across the brain than previously acknowledged. This approach provides a new way to evaluate and constrain computational models with brain activity and pushes our understanding of human brain function further along the spectrum from strict modularity toward distributed representation.

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Brain Function Differences in Language Processing in Children and Adults with Autism

Autism Research ◽

10.1002/aur.1291 ◽

2013 ◽

Vol 6 (4) ◽

pp. 288-302 ◽

Cited By ~ 30

Author(s):

Diane L. Williams ◽

Vladimir L. Cherkassky ◽

Robert A. Mason ◽

Timothy A. Keller ◽

Nancy J. Minshew ◽

...

Keyword(s):

Language Processing ◽

Brain Function ◽

Adults With Autism

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The neural architecture of language: Integrative reverse-engineering converges on a model for predictive processing

10.1101/2020.06.26.174482 ◽

2020 ◽

Cited By ~ 2

Author(s):

Martin Schrimpf ◽

Idan Blank ◽

Greta Tuckute ◽

Carina Kauf ◽

Eghbal A. Hosseini ◽

...

Keyword(s):

Reverse Engineering ◽

Language Processing ◽

Brain Function ◽

Computational Models ◽

Predictive Processing ◽

Neural Responses ◽

Data Types ◽

Neural Architecture ◽

And Behavior ◽

The Brain

AbstractThe neuroscience of perception has recently been revolutionized with an integrative reverse-engineering approach in which computation, brain function, and behavior are linked across many different datasets and many computational models. We here present a first systematic study taking this approach into higher-level cognition: human language processing, our species’ signature cognitive skill. We find that the most powerful ‘transformer’ networks predict neural responses at nearly 100% and generalize across different datasets and data types (fMRI, ECoG). Across models, significant correlations are observed among all three metrics of performance: neural fit, fit to behavioral responses, and accuracy on the next-word prediction task (but not other language tasks), consistent with the long-standing hypothesis that the brain’s language system is optimized for predictive processing. Model architectures with initial weights further perform surprisingly similar to final trained models, suggesting that inherent structure – and not just experience with language – crucially contributes to a model’s match to the brain.

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Role of Astrocytic Mitochondria in Limiting Ischemic Brain Injury?

Physiology ◽

10.1152/physiol.00038.2017 ◽

2018 ◽

Vol 33 (2) ◽

pp. 99-112 ◽

Cited By ~ 3

Author(s):

Evelyn K. Shih ◽

Michael B. Robinson

Keyword(s):

Brain Injury ◽

Neuronal Activity ◽

Brain Function ◽

Functional Significance ◽

Normal Brain ◽

Ischemic Brain Injury ◽

Ischemic Brain ◽

Normal Brain Function

Until recently, astrocyte processes were thought to be too small to contain mitochondria. However, it is now clear that mitochondria are found throughout fine astrocyte processes and are mobile with neuronal activity resulting in positioning near synapses. In this review, we discuss evidence that astrocytic mitochondria confer selective resiliency to astrocytes during ischemic insults and the functional significance of these mitochondria for normal brain function.

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Studies of synaptic elimination identify an intersection of neurocomputational and neurodevelopmental perspectives

Behavioral and Brain Sciences ◽

10.1017/s0140525x00343369 ◽

2000 ◽

Vol 23 (4) ◽

pp. 543-544

Author(s):

Ralph E. Hoffman

Keyword(s):

Neural Network ◽

Temporal Processing ◽

Brain Function ◽

Functional Significance ◽

Network Pruning ◽

Cortical Connections ◽

Computational Capacity ◽

Selective Elimination ◽

Potential Synergy ◽

Shed Light

In order to reach a better understanding of brain function, conceptual synergies linking empirical neurobiological studies and neurocomputational studies should be pursued. I describe an example of a potential synergy based on studies of neural network pruning. Simulations demonstrate that selective elimination of connections enhances the computational capacity of networks capable of temporal processing. These findings may shed light on the functional significance of postnatal neuro-developmental pruning of cortical connections that occurs in mammals.

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Probiotics, Prebiotics and Postbiotics on Mitigation of Depression Symptoms: Modulation of the Brain–Gut–Microbiome Axis

Biomolecules ◽

10.3390/biom11071000 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1000

Author(s):

Agata Chudzik ◽

Anna Orzyłowska ◽

Radosław Rola ◽

Greg J. Stanisz

Keyword(s):

Gut Microbiota ◽

Gut Microbiome ◽

Depressive Disorders ◽

Corticosterone Level ◽

Depression Symptoms ◽

Symptoms Of Depression ◽

Bidirectional Communication ◽

The Central Nervous System ◽

Communication Pathway ◽

The Brain

The brain–gut–microbiome axis is a bidirectional communication pathway between the gut microbiota and the central nervous system. The growing interest in the gut microbiota and mechanisms of its interaction with the brain has contributed to the considerable attention given to the potential use of probiotics, prebiotics and postbiotics in the prevention and treatment of depressive disorders. This review discusses the up-to-date findings in preclinical and clinical trials regarding the use of pro-, pre- and postbiotics in depressive disorders. Studies in rodent models of depression show that some of them inhibit inflammation, decrease corticosterone level and change the level of neurometabolites, which consequently lead to mitigation of the symptoms of depression. Moreover, certain clinical studies have indicated improvement in mood as well as changes in biochemical parameters in patients suffering from depressive disorders.

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The Gut-Brain Axis in Inflammatory Bowel Disease—Current and Future Perspectives

International Journal of Molecular Sciences ◽

10.3390/ijms22168870 ◽

2021 ◽

Vol 22 (16) ◽

pp. 8870

Author(s):

Claudia Günther ◽

Veit Rothhammer ◽

Marisa Karow ◽

Markus Neurath ◽

Beate Winner

Keyword(s):

Brain Function ◽

Molecular Mechanisms ◽

Neurological Diseases ◽

Sequence Of Events ◽

Disease Mechanisms ◽

Bidirectional Communication ◽

Bowel Diseases ◽

The Central Nervous System ◽

Inflammatory Bowel ◽

Human Specific

The gut–brain axis is a bidirectional communication system driven by neural, hormonal, metabolic, immunological, and microbial signals. Signaling events from the gut can modulate brain function and recent evidence suggests that the gut–brain axis may play a pivotal role in linking gastrointestinal and neurological diseases. Accordingly, accumulating evidence has suggested a link between inflammatory bowel diseases (IBDs) and neurodegenerative, as well as neuroinflammatory diseases. In this context, clinical, epidemiological and experimental data have demonstrated that IBD predisposes a person to pathologies of the central nervous system (CNS). Likewise, a number of neurological disorders are associated with changes in the intestinal environment, which are indicative for disease-mediated gut–brain inter-organ communication. Although this axis was identified more than 20 years ago, the sequence of events and underlying molecular mechanisms are poorly defined. The emergence of precision medicine has uncovered the need to take into account non-intestinal symptoms in the context of IBD that could offer the opportunity to tailor therapies to individual patients. The aim of this review is to highlight recent findings supporting the clinical and biological link between the gut and brain, as well as its clinical significance for IBD as well as neurodegeneration and neuroinflammation. Finally, we focus on novel human-specific preclinical models that will help uncover disease mechanisms to better understand and modulate the function of this complex system.

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