Low-dimensional organization of global brain states of reduced consciousness
Yonatan Sanz Perl,
Carla Pallavicini,
Juan Piccinini,
Athena Demertzi,
Vincent Bonhomme,
Charlotte Martial,
Rajanikant Panda,
Naji Alnagger,
Jitka Annen,
Olivia Gosseries,
Agustin Ibañez,
Helmut Laufs,
Jacobo D. Sitt,
Viktor K. Jirsa,
Morten L. Kringelbach,
Steven Laureys,
Gustavo Deco,
Enzo Tagliazucchi
Affiliations
Yonatan Sanz Perl
Department of Physics, University of Buenos Aires, Intendente Guiraldes 2160 (Ciudad Universitaria), Buenos Aires, Argentina; National Scientific and Technical Research Council (CONICET), CABA, Buenos Aires, Argentina; Cognitive Neuroscience Center (CNC), Universidad de San Andrés, Buenos Aires, Argentina; Center for Brain and Cognition, Computational Neuroscience Group, Universitat Pompeu Fabra, Barcelona, Spain; Paris Brain Institute (ICM), Paris, France; Corresponding author
Carla Pallavicini
Department of Physics, University of Buenos Aires, Intendente Guiraldes 2160 (Ciudad Universitaria), Buenos Aires, Argentina; National Scientific and Technical Research Council (CONICET), CABA, Buenos Aires, Argentina; Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI), Buenos Aires, Argentina
Juan Piccinini
Department of Physics, University of Buenos Aires, Intendente Guiraldes 2160 (Ciudad Universitaria), Buenos Aires, Argentina; National Scientific and Technical Research Council (CONICET), CABA, Buenos Aires, Argentina
Athena Demertzi
Physiology of Cognition Research Lab, GIGA CRC-In Vivo Imaging Center, GIGA Institute, University of Liège, Liège, Belgium
Vincent Bonhomme
Anesthesia and Intensive Care Laboratory, GIGA-Consciousness, GIGA Institute, University of Liège, Liège, Belgium; University Department of Anesthesia and Intensive Care Medicine, Centre Hospitalier Régional de la Citadelle (CHR Citadelle), Liège, Belgium; Department of Anesthesia and Intensive Care Medicine, Centre Hospitalier Universitaire de Liège (CHU Liège), Liège, Belgium
Charlotte Martial
Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium; Centre du Cerveau2, Centre Hospitalier Universitaire de Liège (CHU Liège), Liège, Belgium
Rajanikant Panda
Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium; Centre du Cerveau2, Centre Hospitalier Universitaire de Liège (CHU Liège), Liège, Belgium
Naji Alnagger
Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium; Centre du Cerveau2, Centre Hospitalier Universitaire de Liège (CHU Liège), Liège, Belgium
Jitka Annen
Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium; Centre du Cerveau2, Centre Hospitalier Universitaire de Liège (CHU Liège), Liège, Belgium
Olivia Gosseries
Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium; Centre du Cerveau2, Centre Hospitalier Universitaire de Liège (CHU Liège), Liège, Belgium
Agustin Ibañez
National Scientific and Technical Research Council (CONICET), CABA, Buenos Aires, Argentina; Cognitive Neuroscience Center (CNC), Universidad de San Andrés, Buenos Aires, Argentina; Latin American Brain Health Institute (BrainLat), Universidad Adolfo Ibáñez, Santiago, Chile; Global Brain Health Institute (GBHI), University of California-San Francisco (UCSF), San Francisco, CA, USA; Trinity College, Dublin, Ireland
Helmut Laufs
Department of Neurology and Brain Imaging Center, Goethe University, Frankfurt am Main, Germany; Department of Neurology, Christian Albrechts University, Kiel, Germany
Jacobo D. Sitt
Paris Brain Institute (ICM), Paris, France; INSERM U 1127, Paris, France; CNRS UMR 7225, Paris, France
Viktor K. Jirsa
Institut de Neurosciences des Systèmes, Aix Marseille Université, Marseille, France
Morten L. Kringelbach
Department of Psychiatry, University of Oxford, Oxford, UK; Center for Music in the Brain, Department of Clinical Medicine, Aarhus University, Århus, Denmark; Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal; Centre for Eudaimonia and Human Flourishing, University of Oxford, Oxford, UK
Steven Laureys
Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium; Centre du Cerveau2, Centre Hospitalier Universitaire de Liège (CHU Liège), Liège, Belgium
Gustavo Deco
Center for Brain and Cognition, Computational Neuroscience Group, Universitat Pompeu Fabra, Barcelona, Spain; Department of Information and Communication Technologies, Universitat Pompeu Fabra, Barcelona, Spain; Institució Catalana de la Recerca i Estudis Avancats (ICREA), Barcelona, Spain
Enzo Tagliazucchi
Department of Physics, University of Buenos Aires, Intendente Guiraldes 2160 (Ciudad Universitaria), Buenos Aires, Argentina; National Scientific and Technical Research Council (CONICET), CABA, Buenos Aires, Argentina; Centre du Cerveau2, Centre Hospitalier Universitaire de Liège (CHU Liège), Liège, Belgium; Corresponding author
Summary: Brain states are frequently represented using a unidimensional scale measuring the richness of subjective experience (level of consciousness). This description assumes a mapping between the high-dimensional space of whole-brain configurations and the trajectories of brain states associated with changes in consciousness, yet this mapping and its properties remain unclear. We combine whole-brain modeling, data augmentation, and deep learning for dimensionality reduction to determine a mapping representing states of consciousness in a low-dimensional space, where distances parallel similarities between states. An orderly trajectory from wakefulness to patients with brain injury is revealed in a latent space whose coordinates represent metrics related to functional modularity and structure-function coupling, increasing alongside loss of consciousness. Finally, we investigate the effects of model perturbations, providing geometrical interpretation for the stability and reversibility of states. We conclude that conscious awareness depends on functional patterns encoded as a low-dimensional trajectory within the vast space of brain configurations.
