1
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Chis-Ciure R, Melloni L, Northoff G. A measure centrality index for systematic empirical comparison of consciousness theories. Neurosci Biobehav Rev 2024; 161:105670. [PMID: 38615851 DOI: 10.1016/j.neubiorev.2024.105670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Revised: 03/15/2024] [Accepted: 04/08/2024] [Indexed: 04/16/2024]
Abstract
Consciousness science is marred by disparate constructs and methodologies, making it challenging to systematically compare theories. This foundational crisis casts doubts on the scientific character of the field itself. Addressing it, we propose a framework for systematically comparing consciousness theories by introducing a novel inter-theory classification interface, the Measure Centrality Index (MCI). Recognizing its gradient distribution, the MCI assesses the degree of importance a specific empirical measure has for a given consciousness theory. We apply the MCI to probe how the empirical measures of the Global Neuronal Workspace Theory (GNW), Integrated Information Theory (IIT), and Temporospatial Theory of Consciousness (TTC) would fare within the context of the other two. We demonstrate that direct comparison of IIT, GNW, and TTC is meaningful and valid for some measures like Lempel-Ziv Complexity (LZC), Autocorrelation Window (ACW), and possibly Mutual Information (MI). In contrast, it is problematic for others like the anatomical and physiological neural correlates of consciousness (NCC) due to their MCI-based differential weightings within the structure of the theories. In sum, we introduce and provide proof-of-principle of a novel systematic method for direct inter-theory empirical comparisons, thereby addressing isolated evolution of theories and confirmatory bias issues in the state-of-the-art neuroscience of consciousness.
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Affiliation(s)
- Robert Chis-Ciure
- New York University (NYU), New York, USA; International Center for Neuroscience and Ethics (CINET), Tatiana Foundation, Madrid, Spain; Wolfram Physics Project, USA.
| | - Lucia Melloni
- Max Planck Institute for Empirical Aesthetics, Frankfurt am Main, Germany
| | - Georg Northoff
- University of Ottawa, Institute of Mental Health Research at the Royal Ottawa Hospital, Ottawa, Canada
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2
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Konsman JP. Expanding the notion of mechanism to further understanding of biopsychosocial disorders? Depression and medically-unexplained pain as cases in point. STUDIES IN HISTORY AND PHILOSOPHY OF SCIENCE 2024; 103:123-136. [PMID: 38157672 DOI: 10.1016/j.shpsa.2023.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/24/2023] [Accepted: 12/16/2023] [Indexed: 01/03/2024]
Abstract
Evidence-Based Medicine has little consideration for mechanisms and philosophers of science and medicine have recently made pleas to increase the place of mechanisms in the medical evidence hierarchy. However, in this debate the notions of mechanisms seem to be limited to 'mechanistic processes' and 'complex-systems mechanisms,' understood as 'componential causal systems'. I believe that this will not do full justice to how mechanisms are used in biological, psychological and social sciences and, consequently, in a more biopsychosocial approach to medicine. Here, I propose, following (Kuorikoski, 2009), to pay more attention to 'abstract forms of interaction' mechanisms. The present work scrutinized review articles on depression and medically unexplained pain, which are considered to be of multifactorial pathogenesis, for their use of mechanisms. In review articles on these disorders there seemed to be a range of uses between more 'abstract forms of interaction' and 'componential causal system' mechanisms. I therefore propose to expand the notions of mechanisms considered in medicine to include that of more 'abstract forms of interaction' to better explain and manage biopsychosocial disorders.
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Affiliation(s)
- Jan Pieter Konsman
- ImmunoConcEpT, CNRS UMR 5164, University of Bordeaux, 33076, Bordeaux, France.
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3
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Liaghat A, Konsman JP. Methodological advice for the young at heart investigator: Triangulation to build better foundations. Brain Behav Immun 2024; 115:737-746. [PMID: 37972881 DOI: 10.1016/j.bbi.2023.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 10/02/2023] [Accepted: 11/08/2023] [Indexed: 11/19/2023] Open
Abstract
In medicine and science, one is typically taught the main theories in a discipline or field along with standard models before receiving more instructions on how to apply certain methods. The aim of this work is not to address one method, but rather methodology, the study and evaluation of methods, by taking a philosophy of science detour. In this, a critique of biomedicine will be used as a starting point to address some positions regarding reductionism, specifying notions such as systems and mechanisms, as well as regarding the mind-body problem discussing psychosomatic medicine and psychoneuroimmunology. Some recommendations to make science more pluralistic, robust and translationally-relevant will then be made as a way to foster constructive debates on reductionism and the mind-body problem and, in turn, favor more interdisciplinary research.
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Affiliation(s)
- Amirreza Liaghat
- IMMUNOlogy from CONcepts and ExPeriments to Translation, CNRS UMR 5164, University of Bordeaux, 33076 Bordeaux, France
| | - Jan Pieter Konsman
- IMMUNOlogy from CONcepts and ExPeriments to Translation, CNRS UMR 5164, University of Bordeaux, 33076 Bordeaux, France.
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4
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Cea I, Negro N, Signorelli CM. The Fundamental Tension in Integrated Information Theory 4.0's Realist Idealism. ENTROPY (BASEL, SWITZERLAND) 2023; 25:1453. [PMID: 37895574 PMCID: PMC10606349 DOI: 10.3390/e25101453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 09/29/2023] [Accepted: 10/05/2023] [Indexed: 10/29/2023]
Abstract
Integrated Information Theory (IIT) is currently one of the most influential scientific theories of consciousness. Here, we focus specifically on a metaphysical aspect of the theory's most recent version (IIT 4.0), what we may call its idealistic ontology, and its tension with a kind of realism about the external world that IIT also endorses. IIT 4.0 openly rejects the mainstream view that consciousness is generated by the brain, positing instead that consciousness is ontologically primary while the physical domain is just "operational". However, this philosophical position is presently underdeveloped and is not rigorously formulated in IIT, potentially leading to many misinterpretations and undermining its overall explanatory power. In the present paper we aim to address this issue. We argue that IIT's idealistic ontology should be understood as a specific combination of phenomenal primitivism, reductionism regarding Φ-structures and complexes, and eliminativism about non-conscious physical entities. Having clarified this, we then focus on the problematic tension between IIT's idealistic ontology and its simultaneous endorsement of realism, according to which there is some kind of external reality independent of our minds. After refuting three potential solutions to this theoretical tension, we propose the most plausible alternative: understanding IIT's realism as an assertion of the existence of other experiences beyond one's own, what we call a non-solipsistic idealist realism. We end with concluding remarks and future research avenues.
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Affiliation(s)
- Ignacio Cea
- Center for Research, Innovation and Creation, Temuco Catholic University, Temuco 4813302, Chile
- Faculty of Religious Sciences and Philosophy, Temuco Catholic University, Temuco 4813302, Chile
| | - Niccolo Negro
- School of Psychological Sciences, Tel Aviv University, P.O. Box 39040, Tel Aviv 6997801, Israel;
| | - Camilo Miguel Signorelli
- FNRS, GIGA Institute, University of Liege, Rue d’Egmont 5, B-1000 Brussels, Belgium;
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Road, Oxford OX1 3QD, UK
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5
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Albantakis L, Barbosa L, Findlay G, Grasso M, Haun AM, Marshall W, Mayner WGP, Zaeemzadeh A, Boly M, Juel BE, Sasai S, Fujii K, David I, Hendren J, Lang JP, Tononi G. Integrated information theory (IIT) 4.0: Formulating the properties of phenomenal existence in physical terms. PLoS Comput Biol 2023; 19:e1011465. [PMID: 37847724 PMCID: PMC10581496 DOI: 10.1371/journal.pcbi.1011465] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 08/26/2023] [Indexed: 10/19/2023] Open
Abstract
This paper presents Integrated Information Theory (IIT) 4.0. IIT aims to account for the properties of experience in physical (operational) terms. It identifies the essential properties of experience (axioms), infers the necessary and sufficient properties that its substrate must satisfy (postulates), and expresses them in mathematical terms. In principle, the postulates can be applied to any system of units in a state to determine whether it is conscious, to what degree, and in what way. IIT offers a parsimonious explanation of empirical evidence, makes testable predictions concerning both the presence and the quality of experience, and permits inferences and extrapolations. IIT 4.0 incorporates several developments of the past ten years, including a more accurate formulation of the axioms as postulates and mathematical expressions, the introduction of a unique measure of intrinsic information that is consistent with the postulates, and an explicit assessment of causal relations. By fully unfolding a system's irreducible cause-effect power, the distinctions and relations specified by a substrate can account for the quality of experience.
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Affiliation(s)
- Larissa Albantakis
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Leonardo Barbosa
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
- Fralin Biomedical Research Institute at VTC, Virginia Tech, Roanoke, Virginia, United States of America
| | - Graham Findlay
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
- Neuroscience Training Program, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Matteo Grasso
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Andrew M. Haun
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
| | - William Marshall
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
- Department of Mathematics and Statistics, Brock University, St. Catharines, Ontario, Canada
| | - William G. P. Mayner
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
- Neuroscience Training Program, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Alireza Zaeemzadeh
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Melanie Boly
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
- Department of Neurology, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Bjørn E. Juel
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Shuntaro Sasai
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
- Araya Inc., Tokyo, Japan
| | - Keiko Fujii
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Isaac David
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Jeremiah Hendren
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
- Graduate School Language & Literature, Ludwig Maximilian University of Munich, Munich, Germany
| | - Jonathan P. Lang
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Giulio Tononi
- Department of Psychiatry, University of Wisconsin, Madison, Wisconsin, United States of America
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6
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Sadri A. Is Target-Based Drug Discovery Efficient? Discovery and "Off-Target" Mechanisms of All Drugs. J Med Chem 2023; 66:12651-12677. [PMID: 37672650 DOI: 10.1021/acs.jmedchem.2c01737] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/08/2023]
Abstract
Target-based drug discovery is the dominant paradigm of drug discovery; however, a comprehensive evaluation of its real-world efficiency is lacking. Here, a manual systematic review of about 32000 articles and patents dating back to 150 years ago demonstrates its apparent inefficiency. Analyzing the origins of all approved drugs reveals that, despite several decades of dominance, only 9.4% of small-molecule drugs have been discovered through "target-based" assays. Moreover, the therapeutic effects of even this minimal share cannot be solely attributed and reduced to their purported targets, as they depend on numerous off-target mechanisms unconsciously incorporated by phenotypic observations. The data suggest that reductionist target-based drug discovery may be a cause of the productivity crisis in drug discovery. An evidence-based approach to enhance efficiency seems to be prioritizing, in selecting and optimizing molecules, higher-level phenotypic observations that are closer to the sought-after therapeutic effects using tools like artificial intelligence and machine learning.
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Affiliation(s)
- Arash Sadri
- Lyceum Scientific Charity, Tehran, Iran, 1415893697
- Interdisciplinary Neuroscience Research Program (INRP), Students' Scientific Research Center, Tehran University of Medical Sciences, Tehran, Iran, 1417755331
- Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran, 1417614411
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7
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Ellis GFR. Efficient, Formal, Material, and Final Causes in Biology and Technology. ENTROPY (BASEL, SWITZERLAND) 2023; 25:1301. [PMID: 37761600 PMCID: PMC10529506 DOI: 10.3390/e25091301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 08/24/2023] [Accepted: 08/28/2023] [Indexed: 09/29/2023]
Abstract
This paper considers how a classification of causal effects as comprising efficient, formal, material, and final causation can provide a useful understanding of how emergence takes place in biology and technology, with formal, material, and final causation all including cases of downward causation; they each occur in both synchronic and diachronic forms. Taken together, they underlie why all emergent levels in the hierarchy of emergence have causal powers (which is Noble's principle of biological relativity) and so why causal closure only occurs when the upwards and downwards interactions between all emergent levels are taken into account, contra to claims that some underlying physics level is by itself causality complete. A key feature is that stochasticity at the molecular level plays an important role in enabling agency to emerge, underlying the possibility of final causation occurring in these contexts.
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Affiliation(s)
- George F R Ellis
- Mathematics Department, The New Institute, University of Cape Town, 20354 Hamburg, Germany
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8
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McQueen KJ, Tsuchiya N. When do parts form wholes? Integrated information as the restriction on mereological composition. Neurosci Conscious 2023; 2023:niad013. [PMID: 37275559 PMCID: PMC10237036 DOI: 10.1093/nc/niad013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 04/02/2023] [Accepted: 05/23/2023] [Indexed: 06/07/2023] Open
Abstract
Under what conditions are material objects, such as particles, parts of a whole object? This is the composition question and is a longstanding open question in philosophy. Existing attempts to specify a non-trivial restriction on composition tend to be vague and face serious counterexamples. Consequently, two extreme answers have become mainstream: composition (the forming of a whole by its parts) happens under no or all conditions. In this paper, we provide a self-contained introduction to the integrated information theory (IIT) of consciousness. We show that IIT specifies a non-trivial restriction on composition: composition happens when integrated information is maximized. We compare the IIT restriction to existing proposals and argue that the IIT restriction has significant advantages, especially in response to the problems of vagueness and counterexamples. An appendix provides an introduction to calculating parts and wholes with a simple system.
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Affiliation(s)
- Kelvin J McQueen
- Philosophy Department, Chapman University, California, United States
| | - Naotsugu Tsuchiya
- *Correspondence address. Turner Institute for Brain and Mental Health & School of Psychological Sciences, Faculty of Medicine, Nursing, and Health Sciences, Monash University, Melbourne, Victoria, Australia. E-mail:
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9
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Albantakis L, Prentner R, Durham I. Computing the Integrated Information of a Quantum Mechanism. ENTROPY (BASEL, SWITZERLAND) 2023; 25:449. [PMID: 36981337 PMCID: PMC10047696 DOI: 10.3390/e25030449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/22/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
Originally conceived as a theory of consciousness, integrated information theory (IIT) provides a theoretical framework intended to characterize the compositional causal information that a system, in its current state, specifies about itself. However, it remains to be determined whether IIT as a theory of consciousness is compatible with quantum mechanics as a theory of microphysics. Here, we present an extension of IIT's latest formalism to evaluate the mechanism integrated information (φ) of a system subset to discrete, finite-dimensional quantum systems (e.g., quantum logic gates). To that end, we translate a recently developed, unique measure of intrinsic information into a density matrix formulation and extend the notion of conditional independence to accommodate quantum entanglement. The compositional nature of the IIT analysis might shed some light on the internal structure of composite quantum states and operators that cannot be obtained using standard information-theoretical analysis. Finally, our results should inform theoretical arguments about the link between consciousness, causation, and physics from the classical to the quantum.
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Affiliation(s)
- Larissa Albantakis
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA
- Association for Mathematical Consciousness Science, 80539 Munich, Germany
| | - Robert Prentner
- Association for Mathematical Consciousness Science, 80539 Munich, Germany
- Munich Center for Mathematical Philosophy, Ludwig-Maximilians-University, 80539 Munich, Germany
| | - Ian Durham
- Association for Mathematical Consciousness Science, 80539 Munich, Germany
- Department of Physics, Saint Anselm College, Manchester, NH 03102, USA
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10
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Herzog R, Rosas FE, Whelan R, Fittipaldi S, Santamaria-Garcia H, Cruzat J, Birba A, Moguilner S, Tagliazucchi E, Prado P, Ibanez A. Genuine high-order interactions in brain networks and neurodegeneration. Neurobiol Dis 2022; 175:105918. [PMID: 36375407 DOI: 10.1016/j.nbd.2022.105918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 10/18/2022] [Accepted: 11/03/2022] [Indexed: 11/13/2022] Open
Abstract
Brain functional networks have been traditionally studied considering only interactions between pairs of regions, neglecting the richer information encoded in higher orders of interactions. In consequence, most of the connectivity studies in neurodegeneration and dementia use standard pairwise metrics. Here, we developed a genuine high-order functional connectivity (HOFC) approach that captures interactions between 3 or more regions across spatiotemporal scales, delivering a more biologically plausible characterization of the pathophysiology of neurodegeneration. We applied HOFC to multimodal (electroencephalography [EEG], and functional magnetic resonance imaging [fMRI]) data from patients diagnosed with behavioral variant of frontotemporal dementia (bvFTD), Alzheimer's disease (AD), and healthy controls. HOFC revealed large effect sizes, which, in comparison to standard pairwise metrics, provided a more accurate and parsimonious characterization of neurodegeneration. The multimodal characterization of neurodegeneration revealed hypo and hyperconnectivity on medium to large-scale brain networks, with a larger contribution of the former. Regions as the amygdala, the insula, and frontal gyrus were associated with both effects, suggesting potential compensatory processes in hub regions. fMRI revealed hypoconnectivity in AD between regions of the default mode, salience, visual, and auditory networks, while in bvFTD between regions of the default mode, salience, and somatomotor networks. EEG revealed hypoconnectivity in the γ band between frontal, limbic, and sensory regions in AD, and in the δ band between frontal, temporal, parietal and posterior areas in bvFTD, suggesting additional pathophysiological processes that fMRI alone can not capture. Classification accuracy was comparable with standard biomarkers and robust against confounders such as sample size, age, education, and motor artifacts (from fMRI and EEG). We conclude that high-order interactions provide a detailed, EEG- and fMRI compatible, biologically plausible, and psychopathological-specific characterization of different neurodegenerative conditions.
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Affiliation(s)
- Rubén Herzog
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Santiago, Chile; Fundación para el Estudio de la Conciencia Humana (EcoH), Chile
| | - Fernando E Rosas
- Fundación para el Estudio de la Conciencia Humana (EcoH), Chile; Centre for Psychedelic Research, Department of Brain Sciences, Imperial College London, UK; Data Science Institute, Imperial College London, UK; Centre for Complexity Science, Imperial College London, UK; Department of Informatics, University of Sussex, Brighton, UK
| | - Robert Whelan
- Global Brain Health Institute (GBHI), Trinity College Dublin, Dublin 2, Ireland
| | - Sol Fittipaldi
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Santiago, Chile; Global Brain Health Institute (GBHI), Trinity College Dublin, Dublin 2, Ireland; Cognitive Neuroscience Center (CNC), Universidad de San Andrés & CONICET, Buenos Aires, Argentina
| | | | - Josephine Cruzat
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Santiago, Chile; Fundación para el Estudio de la Conciencia Humana (EcoH), Chile
| | - Agustina Birba
- Cognitive Neuroscience Center (CNC), Universidad de San Andrés & CONICET, Buenos Aires, Argentina
| | - Sebastian Moguilner
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Santiago, Chile
| | - Enzo Tagliazucchi
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Santiago, Chile; Buenos Aires Physics Institute and Physics Department, University of Buenos Aires, Buenos Aires, Argentina
| | - Pavel Prado
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Santiago, Chile.
| | - Agustin Ibanez
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Santiago, Chile; Global Brain Health Institute (GBHI), Trinity College Dublin, Dublin 2, Ireland; Cognitive Neuroscience Center (CNC), Universidad de San Andrés & CONICET, Buenos Aires, Argentina; Global Brain Health Institute (GBHI), University of California San Francisco (UCSF), CA, USA.
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11
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Arkhipov A. Non-Separability of Physical Systems as a Foundation of Consciousness. ENTROPY (BASEL, SWITZERLAND) 2022; 24:1539. [PMID: 36359629 PMCID: PMC9689906 DOI: 10.3390/e24111539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/22/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
A hypothesis is presented that non-separability of degrees of freedom is the fundamental property underlying consciousness in physical systems. The amount of consciousness in a system is determined by the extent of non-separability and the number of degrees of freedom involved. Non-interacting and feedforward systems have zero consciousness, whereas most systems of interacting particles appear to have low non-separability and consciousness. By contrast, brain circuits exhibit high complexity and weak but tightly coordinated interactions, which appear to support high non-separability and therefore high amount of consciousness. The hypothesis applies to both classical and quantum cases, and we highlight the formalism employing the Wigner function (which in the classical limit becomes the Liouville density function) as a potentially fruitful framework for characterizing non-separability and, thus, the amount of consciousness in a system. The hypothesis appears to be consistent with both the Integrated Information Theory and the Orchestrated Objective Reduction Theory and may help reconcile the two. It offers a natural explanation for the physical properties underlying the amount of consciousness and points to methods of estimating the amount of non-separability as promising ways of characterizing the amount of consciousness.
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Affiliation(s)
- Anton Arkhipov
- MindScope Program, Allen Institute, Seattle, WA 98109, USA
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12
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Emergence of Integrated Information at Macro Timescales in Real Neural Recordings. ENTROPY 2022; 24:e24050625. [PMID: 35626510 PMCID: PMC9140848 DOI: 10.3390/e24050625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/22/2022] [Accepted: 04/26/2022] [Indexed: 11/17/2022]
Abstract
How a system generates conscious experience remains an elusive question. One approach towards answering this is to consider the information available in the system from the perspective of the system itself. Integrated information theory (IIT) proposes a measure to capture this integrated information (Φ). While Φ can be computed at any spatiotemporal scale, IIT posits that it be applied at the scale at which the measure is maximised. Importantly, Φ in conscious systems should emerge to be maximal not at the smallest spatiotemporal scale, but at some macro scale where system elements or timesteps are grouped into larger elements or timesteps. Emergence in this sense has been demonstrated in simple example systems composed of logic gates, but it remains unclear whether it occurs in real neural recordings which are generally continuous and noisy. Here we first utilise a computational model to confirm that Φ becomes maximal at the temporal scales underlying its generative mechanisms. Second, we search for emergence in local field potentials from the fly brain recorded during wakefulness and anaesthesia, finding that normalised Φ (wake/anaesthesia), but not raw Φ values, peaks at 5 ms. Lastly, we extend our model to investigate why raw Φ values themselves did not peak. This work extends the application of Φ to simple artificial systems consisting of logic gates towards searching for emergence of a macro spatiotemporal scale in real neural systems.
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13
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Ellia F, Chis-Ciure R. Consciousness and complexity: Neurobiological naturalism and integrated information theory. Conscious Cogn 2022; 100:103281. [PMID: 35325632 DOI: 10.1016/j.concog.2022.103281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 01/14/2022] [Accepted: 01/15/2022] [Indexed: 02/03/2023]
Abstract
In this paper we take a meta-theoretical stance and compare and assess two conceptual frameworks that endeavor to explain phenomenal experience. In particular, we compare Feinberg & Mallatt's Neurobiological Naturalism (NN) and Tononi's and colleagues Integrated Information Theory (IIT), given that the former pointed out some similarities between the two theories (Feinberg & Mallatt 2016c-d). To probe their similarity, we first give a general introduction into both frameworks. Next, we expound a ground-plan for carrying out our analysis. We move on to articulate a philosophical profile of NN and IIT, addressing their ontological commitments and epistemological foundations. Finally, we compare the two point-by-point, also discussing how they stand on the issue of artificial consciousness.
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Affiliation(s)
- Francesco Ellia
- School of Medicine, Department of Psychiatry, University of Wisconsin-Madison, United States.
| | - Robert Chis-Ciure
- School of Medicine, Department of Psychiatry, University of Wisconsin-Madison, United States; Faculty of Philosophy, Department of Theoretical Philosophy, University of Bucharest, Romania
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14
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Vollenweider FX, Smallridge JW. Classic Psychedelic Drugs: Update on Biological
Mechanisms. PHARMACOPSYCHIATRY 2022; 55:121-138. [PMID: 35079988 PMCID: PMC9110100 DOI: 10.1055/a-1721-2914] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Renewed interest in the effects of psychedelics in the treatment of psychiatric
disorders warrants a better understanding of the neurobiological mechanisms
underlying the effects of these substances. During the past two decades,
state-of-the-art studies of animals and humans have yielded new important
insights into the molecular, cellular, and systems-level actions of psychedelic
drugs. These efforts have revealed that psychedelics affect primarily
serotonergic receptor subtypes located in cortico-thalamic and cortico-cortical
feedback circuits of information processing. Psychedelic drugs modulate
excitatory-inhibitory balance in these circuits and can participate in
neuroplasticity within brain structures critical for the integration of
information relevant to sensation, cognition, emotions, and the narrative of
self. Neuroimaging studies showed that characteristic dimensions of the
psychedelic experience obtained through subjective questionnaires as well as
alterations in self-referential processing and emotion regulation obtained
through neuropsychological tasks are associated with distinct changes in brain
activity and connectivity patterns at multiple-system levels. These recent
results suggest that changes in self-experience, emotional processing, and
social cognition may contribute to the potential therapeutic effects of
psychedelics.
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Affiliation(s)
- Franz X. Vollenweider
- Neuropsychopharmacology and Brain Imaging, Department of Psychiatry,
Psychotherapy and Psychosomatics, University Hospital for Psychiatry Zurich,
Zurich, Switzerland
| | - John W. Smallridge
- Neuropsychopharmacology and Brain Imaging, Department of Psychiatry,
Psychotherapy and Psychosomatics, University Hospital for Psychiatry Zurich,
Zurich, Switzerland
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