Sanz Perl, YonatanPallavicini, CarlaPérez Ipiña, IgnacioDemertz, AthenaBonhomme, VincentMartial, CharlottePanda, RajanikantAnnen, JitkaIbañez, AgustinKringelbach, Morten L.Deco, GustavoLaufs, HelmutSitt, JacoboLaureys, StevenTagliazucchi, Enzo2022-06-292022-06-292021Sanz Perl Y, Pallavicini C, Pérez Ipiña I, Demertzi A, Bonhomme V, Martial C, Panda R, Annen J, Ibañez A, Kringelbach M, Deco G, Laufs H, Sitt J, Laureys S, Tagliazucchi E. Perturbations in dynamical models of wholebrain activity dissociate between the level and stability of consciousness. PLoS Comput Biol. 2021;17(7):e1009139. DOI: 10.1371/journal. pcbi.10091391553-734Xhttp://hdl.handle.net/10230/53625Consciousness transiently fades away during deep sleep, more stably under anesthesia, and sometimes permanently due to brain injury. The development of an index to quantify the level of consciousness across these different states is regarded as a key problem both in basic and clinical neuroscience. We argue that this problem is ill-defined since such an index would not exhaust all the relevant information about a given state of consciousness. While the level of consciousness can be taken to describe the actual brain state, a complete characterization should also include its potential behavior against external perturbations. We developed and analyzed whole-brain computational models to show that the stability of conscious states provides information complementary to their similarity to conscious wakefulness. Our work leads to a novel methodological framework to sort out different brain states by their stability and reversibility, and illustrates its usefulness to dissociate between physiological (sleep), pathological (brain-injured patients), and pharmacologically-induced (anesthesia) loss of consciousness.application/pdfeng© 2021 Sanz Perl et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Perturbations in dynamical models of wholebrain activity dissociate between the level and stability of consciousnessinfo:eu-repo/semantics/articlehttp://doi.org/10.1371/journal.pcbi.1009139info:eu-repo/semantics/openAccess