Spatiotemporal structure of the spontaneous activity of the brain: modeling and comparison to experimental data

Consciousness is neuronal as it is based on the brain and its neural activity. This is what neuroscience tell us citing strong empirical evidence. At the same time, consciousness is ecological in that it extends beyond the brain to body and world – this is what philosophers tell us when they invoke concepts like embodiment, embeddedness, extendedness, and enactment. Is consciousness neuronal or ecological? This amounts to what I describe as “argument of inclusion”: do we need to include body and world in our account of the brain and how is that very same inclusion important for consciousness? I argue that the “spatiotemporal model” of consciousness can well address the “argument of inclusion” by linking and integrating both neuronal and ecological characterizations of consciousness. I demonstrate various data showing how the brain’s spontaneous activity couples and aligns itself to the spatiotemporal structure in the ongoing activities of both body and world. That amounts to a specific spatiotemporal mechanism of the brain that I describe as ‘spatiotemporal alignment’. Conceptually, such ‘spatiotemporal alignment’ corresponds to “body-brain relation” and “world-brain relation”, as I say. World-brain relation and body-brain relation allow for spatiotemporal relation and integration between the different spatiotemporal scales or ranges of world, body, and brain with all three being spatiotemporally aligned and nested within each other. Based on various empirical findings, I argue that such spatiotemporal nestedness between world, body, and brain establishes a “neuro-ecological continuum” and world-brain relation. Both neuro-ecological continuum and world-brain relation are here understood in an empirical sense and can be regarded as necessary condition of possible consciousness, i.e., neural predisposition of consciousness (NPC) (as distinguished from the neural correlates of consciousness/NCC). In sum, the spatiotemporal model determines consciousness by “neuro-ecological continuum” and world-brain relation (with body-brain relation being a subset). Taken in such sense, the spatiotemporal model can well address the “argument of inclusion”. We need to include body and world in our account of the brain in terms of “neuro-ecological continuum” and world-brain relation since otherwise, due to their role as NPC, consciousness remains impossible.

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Spatiotemporal Model of Consciousness I: Spatiotemporal Specificity and Neuronal-Phenomenal Correspondence

The Spontaneous Brain ◽

10.7551/mitpress/9780262038072.003.0007 ◽

2018 ◽

pp. 151-194

Author(s):

Georg Northoff

Keyword(s):

Spontaneous Activity ◽

Neural Activity ◽

Neural Processing ◽

Central Question ◽

Neural Correlate ◽

Spatiotemporal Structure ◽

Spatiotemporal Model ◽

The Brain ◽

Spatiotemporal Integration

How and why can neural activity in general and specifically stimulus-induced activity be associated with consciousness? This is the central question in the present chapter. I suggest a Spatiotemporal model that conceives both brain and consciousness in predominantly Spatiotemporal terms rather than being based on specific contents and their neural processing by the brain. This amounts to a Spatiotemporal theory of consciousness (STC). I discuss two specific Spatiotemporal mechanisms that I deem relevant for consciousness. The first Spatiotemporal mechanism refers to “Spatiotemporal integration and nestedness” that describe how different frequencies/regions are coupled and linked, i.e., integrated, and subsequently contained, i.e., nested, with each other. Again, based on empirical findings, “Spatiotemporal integration and nestedness” may predispose the level/state of consciousness, i.e., NPC. The second Spatiotemporal mechanism consists in “Spatiotemporal expansion” that allows to expand the stimuli’ specific points in time and space beyond itself by the brain’s spontaneous activity and its spatiotemporal structure. Based on various empirical findings, I suggest “Spatiotemporal expansion” a sufficient neural condition of consciousness, i.e., a neural correlate of the content of consciousness (NCC). Both spatiotemporal mechanisms are specific in that they can distinguish consciousness and unconsciousness: there is “Spatiotemporal expansion” rather than “Spatiotemporal constriction” and there is “Spatiotemporal nestedness” rather than “Spatiotemporal isolation”. This illustrates the specificity of the Spatiotemporal mechanisms which argues against what can be described as “argument of non-specificity”. Moreover, the STC is based on Spatiotemporal mechanisms rather than mere Spatiotemporal features which renders our Spatiotemporal model non-trivial which can be put forward against what can be described as “argument of triviality”. Taken together, the Spatiotemporal model of consciousness as suggested in the STC is neither non-specific but specific in empirical terms nor trivial on conceptual-logical, phenomenal, and ontological grounds.

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A global framework for a systemic view of brain modeling

Brain Informatics ◽

10.1186/s40708-021-00126-4 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Frederic Alexandre

Keyword(s):

Instrumental Conditioning ◽

The Body ◽

Posterior Cortex ◽

Reciprocal Relationships ◽

Brain Modeling ◽

Brain Theory ◽

Habitual Behavior ◽

Definition Of ◽

The Brain ◽

Specific Contribution

AbstractThe brain is a complex system, due to the heterogeneity of its structure, the diversity of the functions in which it participates and to its reciprocal relationships with the body and the environment. A systemic description of the brain is presented here, as a contribution to developing a brain theory and as a general framework where specific models in computational neuroscience can be integrated and associated with global information flows and cognitive functions. In an enactive view, this framework integrates the fundamental organization of the brain in sensorimotor loops with the internal and the external worlds, answering four fundamental questions (what, why, where and how). Our survival-oriented definition of behavior gives a prominent role to pavlovian and instrumental conditioning, augmented during phylogeny by the specific contribution of other kinds of learning, related to semantic memory in the posterior cortex, episodic memory in the hippocampus and working memory in the frontal cortex. This framework highlights that responses can be prepared in different ways, from pavlovian reflexes and habitual behavior to deliberations for goal-directed planning and reasoning, and explains that these different kinds of responses coexist, collaborate and compete for the control of behavior. It also lays emphasis on the fact that cognition can be described as a dynamical system of interacting memories, some acting to provide information to others, to replace them when they are not efficient enough, or to help for their improvement. Describing the brain as an architecture of learning systems has also strong implications in Machine Learning. Our biologically informed view of pavlovian and instrumental conditioning can be very precious to revisit classical Reinforcement Learning and provide a basis to ensure really autonomous learning.

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Development of Regulation of Food Intake by the Gut and the Brain: Modeling in Animals

Handbook of Behavior, Food and Nutrition ◽

10.1007/978-0-387-92271-3_26 ◽

2011 ◽

pp. 387-403

Author(s):

Takashi Higuchi ◽

Chuma O. Okere

Keyword(s):

Food Intake ◽

Brain Modeling ◽

The Brain

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Differential Involvement of Projection Neurons During Emergence of Spontaneous Activity in the Developing Avian Hindbrain

Journal of Neurophysiology ◽

10.1152/jn.90835.2008 ◽

2009 ◽

Vol 101 (2) ◽

pp. 591-602 ◽

Cited By ~ 4

Author(s):

Hiraku Mochida ◽

Gilles Fortin ◽

Jean Champagnat ◽

Joel C. Glover

Keyword(s):

Spontaneous Activity ◽

Projection Neuron ◽

Projection Neurons ◽

Charge Coupled Device ◽

Neuron Populations ◽

Motor Nerves ◽

Differential Involvement ◽

A Charge ◽

The Brain ◽

Calcium Green

To better characterize the emergence of spontaneous neuronal activity in the developing hindbrain, spontaneous activity was recorded optically from defined projection neuron populations in isolated preparations of the brain stem of the chicken embryo. Ipsilaterally projecting reticulospinal (RS) neurons and several groups of vestibuloocular (VO) neurons were labeled retrogradely with Calcium Green-1 dextran amine and spontaneous calcium transients were recorded using a charge-coupled-device camera mounted on a fluorescence microscope. Simultaneous extracellular recordings were made from one of the trigeminal motor nerves (nV) to register the occurrence of spontaneous synchronous bursts of activity. Two types of spontaneous activity were observed: synchronous events (SEs), which occurred in register with spontaneous bursts in nV once every few minutes and were tetrodotoxin (TTX) dependent, and asynchronous events (AEs), which occurred in the intervals between SEs and were TTX resistant. AEs occurred developmentally before SEs and were in general smaller and more variable in amplitude than SEs. SEs appeared at the same stage as nV bursts early on embryonic day 4, first in RS neurons and then in VO neurons. All RS neurons participated equally in SEs from the outset, whereas different subpopulations of VO neurons participated differentially, both in terms of the proportion of neurons that exhibited SEs, the fidelity with which the SEs in individual neurons followed the nV bursts, and the developmental stage at which SEs appeared and matured. The results show that spontaneous activity is expressed heterogeneously among hindbrain projection neuron populations, suggesting its differential involvement in the formation of different functional neuronal circuits.

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Task-Driven Activity Reduces the Cortical Activity Space of the Brain: Experiment and Whole-Brain Modeling

PLoS Computational Biology ◽

10.1371/journal.pcbi.1004445 ◽

2015 ◽

Vol 11 (8) ◽

pp. e1004445 ◽

Cited By ~ 42

Author(s):

Adrián Ponce-Alvarez ◽

Biyu J. He ◽

Patric Hagmann ◽

Gustavo Deco

Keyword(s):

Cortical Activity ◽

Activity Space ◽

Whole Brain ◽

Brain Modeling ◽

The Brain

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Blindfold learning of an accurate neural metric

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1718710115 ◽

2018 ◽

Vol 115 (13) ◽

pp. 3267-3272 ◽

Cited By ~ 6

Author(s):

Christophe Gardella ◽

Olivier Marre ◽

Thierry Mora

Keyword(s):

Ganglion Cells ◽

Direct Access ◽

Retinal Ganglion ◽

Boltzmann Machine ◽

Correlated Responses ◽

Population Activity ◽

Spatiotemporal Structure ◽

Distance Map ◽

Physical Stimuli ◽

The Brain

The brain has no direct access to physical stimuli but only to the spiking activity evoked in sensory organs. It is unclear how the brain can learn representations of the stimuli based on those noisy, correlated responses alone. Here we show how to build an accurate distance map of responses solely from the structure of the population activity of retinal ganglion cells. We introduce the Temporal Restricted Boltzmann Machine to learn the spatiotemporal structure of the population activity and use this model to define a distance between spike trains. We show that this metric outperforms existing neural distances at discriminating pairs of stimuli that are barely distinguishable. The proposed method provides a generic and biologically plausible way to learn to associate similar stimuli based on their spiking responses, without any other knowledge of these stimuli.

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Behavioral and Neurophysiological Demonstration of a Lateralis Skin Photosensitivity in Larval Sea Lampreys

Journal of Experimental Biology ◽

10.1242/jeb.161.1.97 ◽

1991 ◽

Vol 161 (1) ◽

pp. 97-117 ◽

Cited By ~ 1

Author(s):

MARK RONAN ◽

DAVID BODZNICK

Keyword(s):

Spontaneous Activity ◽

Lateral Line ◽

Lateral Line Nerve ◽

Medial Nucleus ◽

Posterior Lateral Line ◽

Behavioral Studies ◽

Sea Lampreys ◽

Response Thresholds ◽

The Brain ◽

Skin Photosensitivity

Larval lampreys respond to skin illumination with a delayed burst of swimming in an attempt to escape the light. The photoresponse, which is independent of the lateral eyes and pineal organs, is most readily elicited by light shone on the tail. Behavioral studies in larval lampreys demonstrate that photosensory afferents innervating the tail are carried by a trunk lateral line nerve supplying regions caudal to the head. The present results confirm that bilateral transection of this nerve in larval sea lampreys markedly diminishes the photoresponse. The trunk lateral line nerve consists of the recurrent ramus of the anterior lateral line nerve and a ramus of the posterior lateral line nerve. Bilateral transection of the recurrent ramus does not affect the photoresponse, indicating that lateralis photosensory afferents enter the brain via the posterior lateral line nerve and terminate in the medial octavolateralis nucleus. Photosensory units were subsequently recorded in the trunk lateral line nerve, posterior lateral line nerve and the lateral line area of the medulla. Medullary photosensory units were localized to the medial nucleus, previously regarded as the primary mechanosensory nucleus. Photosensory units in lateral line nerves and the brain exhibited low, irregular spontaneous activity and, after latencies of 17–4 s, responded to tail illumination with repeated impulse bursts. Response thresholds were 0.1-0.9 mWcm−2. Responses to sustained illumination were slowly adapting. A skin photosense is thus an additional lateralis modality in lampreys.

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COVID-19 Beyond the Lungs

10.4018/978-1-7998-8225-1.ch007 ◽

2022 ◽

pp. 109-126

Author(s):

Omar El Hiba ◽

Hicham Chatoui ◽

Nadia Zouhairi ◽

Lahoucine Bahi ◽

Lhoussaine Ammouta ◽

...

Keyword(s):

Experimental Data ◽

Nervous System ◽

Clinical Symptoms ◽

Case Reports ◽

The World ◽

Acute Pneumonia ◽

The Brain ◽

Cardinal Feature ◽

Shed Light

Since December 2019, the world has been shaken by the spread of a highly pathogen virus, causing severe acute respiratory syndrome (SARS-Cov2), which emerged in Wuhan, China. SARS-Cov2 is known to cause acute pneumonia: the cardinal feature of coronavirus disease 2019 (COVID-19). Clinical features of the disease include respiratory distress, loss of spontaneous breathing, and sometimes neurologic signs such as headache and nausea and anosmia, leading to suppose a possible involvement of the nervous system as a potential target of SARS-CoV2. The chapter will shed light on the recent clinical and experimental data sustaining the involvement of the nervous system in the pathophysiology of COVID-19, based on several case reports and experimental data reporting the possible transmission of SARS-CoV2 throughout the peripheral nerves to the brain cardiorespiratory centers. Thus, understanding the role of the nervous system in the course of clinical symptoms of COVID-19 is important in determining the appropriate therapeutic approach to combat the disease.

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