arXiv Preprint Archive
December 19, 2020
Yonatan Sanz Perl, Hernan Bocaccio, Ignacio Perez-Ipina et al.
The cognitive functions of human and non-human primates rely on the dynamic interplay of distributed neural assemblies. As such, it seems unlikely that cognition can be supported by macroscopic brain dynamics at the proximity of thermodynamic equilibrium. We confirmed this hypothesis by investigating electrocorticography data from non human primates undergoing different states of...
Neuroimage
November 1, 2020
Gerald J. Hahn, Gorka Zamora-López, Lynn Uhrig et al.
55 citations
During the sleep-wake cycle, the brain undergoes profound dynamical changes, which manifest subjectively as transitions between conscious experience and unconsciousness. Yet, neurophysiological signatures that can objectively distinguish different consciousness states based are scarce. Here, we show that differences in the level of brain-wide signals can reliably distinguish different stages of...
bioRxiv Preprint Server
July 2, 2020
Yonatan Sanz Perl, Carla Pallavicini, Ignacio Perez-Ipina et al.
preprint
Consciousness 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...
bioRxiv Preprint Server
June 4, 2020
Camilo Miguel Signorelli, Lynn Uhrig, Morten L. Kringelbach et al.
preprint
Anesthesia induces a reconfiguration of the repertoire of functional brain states leading to a high function-structure similarity. However, it is unclear how these functional changes lead to loss of consciousness. Here we suggest that the mechanism of conscious access is related to a general dynamical rearrangement of the intrinsic hierarchical organization of the cortex. To measure cortical...
Proceedings of the National Academy of Sciences
April 13, 2020
Morten L. Kringelbach, Josephine Cruzat, Joana Cabral et al.
326 citations
Significance In a technical tour de force, we have created a framework demonstrating the underlying fundamental principles of bidirectional coupling of neuronal and neurotransmitter dynamical systems. Specifically, in the present study, we combined multimodal neuroimaging data to causally explain the functional effects of specific serotoninergic receptor (5-HT 2A R) stimulation with psilocybin...
Neuroimage
April 11, 2020
Ignacio Perez-Ipina, Patricio Donnelly Kehoe, Morten L. Kringelbach et al.
81 citations
Global brain states are frequently placed within a unidimensional continuum by correlational studies, ranging from states of deep unconsciousness to ordinary wakefulness. An alternative is their multidimensional and mechanistic characterization in terms of different cognitive capacities, using computational models to reproduce the underlying neural dynamics. We explore this alternative by...
Neuroimage
May 25, 2019
Louis-David Lord, Paul Expert, Selen Atasoy et al.
249 citations
Growing evidence from the dynamical analysis of functional neuroimaging data suggests that brain function can be understood as the exploration of a repertoire of metastable connectivity patterns ('functional brain networks'), which potentially underlie different mental processes. The present study characterizes how the brain's dynamical exploration of resting-state networks is rapidly modulated...
Science Advances
February 1, 2019
Athena Demertzi, Enzo Tagliazucchi, Stanislas Dehaene et al.
545 citations
Adopting the framework of brain dynamics as a cornerstone of human consciousness, we determined whether dynamic signal coordination provides specific and generalizable patterns pertaining to conscious and unconscious states after brain damage. A dynamic pattern of coordinated and anticoordinated functional magnetic resonance imaging signals characterized healthy individuals and minimally...
Prog Brain Res
October 25, 2018
Selen Atasoy, Jakub Vohryzek, Gustavo Deco et al.
67 citations
Common neural signatures of psychedelics: Frequency-specific energy changes and repertoire expansion revealed using connectome-harmonic decomposition.
Curr Biol
September 27, 2018
Gustavo Deco, Josephine Cruzat, Joana Cabral et al.
246 citations
Understanding the underlying mechanisms of the human brain in health and disease will require models with necessary and sufficient details to explain how function emerges from the underlying anatomy and is shaped by neuromodulation. Here, we provide such a detailed causal explanation using a whole-brain model integrating multimodal imaging in healthy human participants undergoing manipulation...
bioRxiv (Cold Spring Harbor Laboratory)
July 25, 2018
Louis-David Lord, Paul Expert, Selen Atasoy et al.
10 citations
preprint
Abstract Brain activity can be understood as the exploration of a dynamical landscape of activity configurations over both space and time. This dynamical landscape may be defined in terms of spontaneous transitions within a repertoire of discrete metastable states of functional connectivity (FC), which underlie different mental processes. However, it remains unclear how the brain’s dynamical...
Sci Rep
December 15, 2017
Selen Atasoy, Leor Roseman, Mendel Kaelen et al.
225 citations
Recent studies have started to elucidate the effects of lysergic acid diethylamide (LSD) on the human brain but the underlying dynamics are not yet fully understood. Here we used 'connectome-harmonic decomposition', a novel method to investigate the dynamical changes in brain states. We found that LSD alters the energy and the power of individual harmonic brain states in a frequency-selective...
The Neuroscientist
September 1, 2017
Selen Atasoy, Gustavo Deco, Morten L. Kringelbach et al.
131 citations
A fundamental characteristic of spontaneous brain activity is coherent oscillations covering a wide range of frequencies. Interestingly, these temporal oscillations are highly correlated among spatially distributed cortical areas forming structured correlation patterns known as the resting state networks, although the brain is never truly at "rest." Here, we introduce the concept of harmonic...
Current Biology
February 20, 2016
Raphael Kaplan, Mohit H. Adhikari, Rikkert Hindriks et al.
127 citations
The default mode network (DMN) is a commonly observed resting-state network (RSN) that includes medial temporal, parietal, and prefrontal regions involved in episodic memory [1-3]. The behavioral relevance of endogenous DMN activity remains elusive, despite an emerging literature correlating resting fMRI fluctuations with memory performance [4, 5]-particularly in DMN regions [6-8]. Mechanistic...
Cerebral Cortex
July 10, 2013
Gustavo Deco, P. Hagmann, Anthony G. Hudetz et al.
99 citations
The transition from wakefulness to sleep represents the most conspicuous change in behavior and the level of consciousness occurring in the healthy brain. It is accompanied by similarly conspicuous changes in neural dynamics, traditionally exemplified by the change from "desynchronized" electroencephalogram activity in wake to globally synchronized slow wave activity of early sleep. However,...
Journal of Neuroscience
March 7, 2012
Gustavo Deco, Viktor Jirsa
778 citations
The ongoing activity of the brain at rest, i.e., under no stimulation and in absence of any task, is astonishingly highly structured into spatiotemporal patterns. These spatiotemporal patterns, called resting state networks, display low-frequency characteristics (<0.1 Hz) observed typically in the BOLD-fMRI signal of human subjects. We aim here to understand the origins of resting state...
PLoS Computational Biology
November 7, 2007
Marco Loh, Edmund T Rolls, Gustavo Deco
172 citations
We propose a top-down approach to the symptoms of schizophrenia based on a statistical dynamical framework. We show that a reduced depth in the basins of attraction of cortical attractor states destabilizes the activity at the network level due to the constant statistical fluctuations caused by the stochastic spiking of neurons. In integrate-and-fire network simulations, a decrease in the NMDA...
Noam Goldway, Taly Markovits, Naomi Fine et al.
preprint
Dissociation, an altered state of consciousness in which individuals feel detached from their body, environment, and sense of self, is a common feature of Post-Traumatic Stress Disorder (PTSD). Despite its significance, the neurocognitive processes underlying dissociation remain poorly understood, potentially limiting the effectiveness of PTSD diagnostics and treatment. To address this gap, we...
Anira Escrichs, Ana Sanjuán, Selen Atasoy et al.
preprint
Abstract Over the past 2,500 years, contemplative traditions have explored the nature of the mind using meditation. More recently, neuroimaging research on meditation has revealed differences in brain function and structure in meditators. Nevertheless, the underlying neural mechanisms are still unclear. In order to understand how meditation shapes global activity through the brain, we...