Interface Focus
April 14, 2023
Elvira G-Guzmán, Yonatan Sanz Perl, Jakub Vohryzek et al.
34 citations
Life is a constant battle against equilibrium. From the cellular level to the macroscopic scale, living organisms as dissipative systems require the violation of their detailed balance, i.e. metabolic enzymatic reactions, in order to survive. We present a framework based on temporal asymmetry as a measure of non-equilibrium. By means of statistical physics, it was discovered that temporal...
Proceedings of the National Academy of Sciences of the United States of America
March 28, 2023
Christopher Timmermann, Leor Roseman, Sharad Haridas et al.
217 citations
Psychedelics have attracted medical interest, but their effects on human brain function are incompletely understood. In a comprehensive, within-subjects, placebo-controlled design, we acquired multimodal neuroimaging [i.e., EEG-fMRI (electroencephalography-functional MRI)] data to assess the effects of intravenous (IV) N,N-Dimethyltryptamine (DMT) on brain function in 20 healthy volunteers....
Network Neuroscience
December 23, 2022
Gustavo Deco, Yonatan Sanz Perl, Laura De la Fuente et al.
43 citations
A promising idea in human cognitive neuroscience is that the default mode network (DMN) is responsible for coordinating the recruitment and scheduling of networks for computing and solving task-specific cognitive problems. This is supported by evidence showing that the physical and functional distance of DMN regions is maximally removed from sensorimotor regions containing environment-driven...
Research Square
October 26, 2022
Rubén Herzog, Pedro A. M. Mediano, Fernando E. Rosas et al.
6 citations
Abstract Psychedelic drugs, including lysergic acid diethylamide (LSD) and other agonists of the serotonin 2A receptor (5HT2A-R), induce drastic changes in subjective experience, and provide a unique opportunity to study the neurobiological basis of consciousness. One of the most notable neurophysiological signatures of psychedelics, increased entropy in spontaneous neural activity, is thought...
bioRxiv Preprint Server
September 28, 2022
Yonatan Sanz Perl, Carla Pallavicini, Juan Piccinini et al.
preprint
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 unknown. We combined whole-brain...
Sci Rep
September 15, 2022
Rubén Herzog, Pedro A. M. Mediano, Fernando E. Rosas et al.
3 citations
s attention that there was a typo in the script used to calculate the differential entropy. Therefore, the reported entropy estimations are invalid and do not produce the expected increase in entropy when using
Psychopharmacology
September 1, 2022
Camila Sanz, Federico Cavanna, Stephanie Müller et al.
1 citation
Serotonergic psychedelics are being studied as novel treatments for mental health disorders and as facilitators of improved well-being, mental function, and creativity. Recent studies have found mixed results concerning the effects of low doses of psychedelics ("microdosing") on these domains. However, microdosing is generally investigated using instruments designed to assess larger doses of...
Translational Psychiatry
August 2, 2022
Federico Cavanna, Stephanie Müller, Laura Alethia de la Fuente et al.
130 citations
Abstract The use of low sub-perceptual doses of psychedelics (“microdosing”) has gained popularity in recent years. Although anecdotal reports claim multiple benefits associated with this practice, the lack of placebo-controlled studies severely limits our knowledge of microdosing and its effects. Moreover, research conducted in standard laboratory settings could fail to capture the motivation...
arXiv Preprint Archive
July 11, 2022
Matthieu Gilson, Enzo Tagliazucchi, Rodrigo Cofré
Consciousness is supported by complex patterns of brain activity which are indicative of irreversible non-equilibrium dynamics. While the framework of stochastic thermodynamics has facilitated the understanding of physical systems of this kind, its application to infer the level of consciousness from empirical data remains elusive. We faced this challenge by calculating entropy production in a...
Physical Review E
July 11, 2022
Matthieu Gilson, Enzo Tagliazucchi, Rodrigo Cofré
Consciousness is supported by complex patterns of brain activity which are indicative of irreversible nonequilibrium dynamics. While the framework of stochastic thermodynamics has facilitated the understanding of physical systems of this kind, its application to infer the level of consciousness from empirical data remains elusive. We faced this challenge by calculating entropy production in a...
Communications Biology
June 29, 2022
Anira Escrichs, Yonatan Sanz Perl, Carme Uribe et al.
67 citations
Significant advances have been made by identifying the levels of synchrony of the underlying dynamics of a given brain state. This research has demonstrated that non-conscious dynamics tend to be more synchronous than in conscious states, which are more asynchronous. Here we go beyond this dichotomy to demonstrate that different brain states are underpinned by dissociable spatiotemporal...
Frontiers in Pharmacology
March 22, 2022
Enzo Tagliazucchi
20 citations
Psychedelics are drugs capable of eliciting profound alterations in the subjective experience of the users, sometimes with long-lasting consequences. Because of this, psychedelic research tends to focus on human subjects, given their capacity to construct detailed narratives about the contents of their consciousness experiences. In spite of its relevance, the interaction between serotonergic...
Network Neuroscience
2022
Josephine Cruzat, Yonatan Sanz Perl, Anira Escrichs et al.
28 citations
Abstract Psychedelic drugs show promise as safe and effective treatments for neuropsychiatric disorders, yet their mechanisms of action are not fully understood. A fundamental hypothesis is that psychedelics work by dose-dependently changing the functional hierarchy of brain dynamics, but it is unclear whether different psychedelics act similarly. Here, we investigated the changes in the...
bioRxiv (Cold Spring Harbor Laboratory)
December 7, 2021
Federico Cavanna, Stephanie Müller, Laura Alethia de la Fuente et al.
8 citations
preprint
Abstract The use of low sub-hallucinogenic doses of psychedelics (“microdosing”) has gained popularity in recent years. Although anecdotal reports claim multiple benefits associated with this practice, the lack of placebo-controlled studies limits our knowledge of microdosing and its effects. Moreover, research conducted in laboratory settings might fail to capture the motivation of individuals...
Preprints.org
November 10, 2021
Enzo Tagliazucchi
5 citations
preprint
Psychedelics are drugs capable of eliciting profound alterations in the subjective experience of the users, sometimes with long-lasting consequences. Because of this, psychedelic research tends to focus on human subjects, given their capacity to construct detailed narratives about the contents of their consciousness experiences. In spite of its relevance, the interaction between serotonergic...
Frontiers in Psychiatry
November 5, 2021
Enzo Tagliazucchi, Federico Zamberlán, Federico Cavanna et al.
23 citations
N,N-Dimethyltryptamine (DMT) is a classic psychedelic capable of inducing short-lasting but profound changes in consciousness. As with other psychedelics, the experience induced by DMT strongly depends upon contextual factors, yet the neurobiological determinants of this variability remain unknown. The present study investigated changes in neural oscillations elicited by inhaled DMT, and...
bioRxiv Preprint Server
September 2, 2021
Laura De la Fuente, Federico Zamberlán, Hernan Bocaccio et al.
preprint
Even though the fundamental laws of physics are the same when the direction of time is inverted, dissipative systems evolve in the preferred temporal direction indicated by the thermodynamic arrow of time. The fundamental nature of this temporal asymmetry led us to hypothesize its presence in the neural activity evoked by conscious perception of the physical world, and thus its covariance with...
Chaos An Interdisciplinary Journal of Nonlinear Science
September 1, 2021
Sofía Morena del Pozo, Helmut Laufs, Vincent Bonhomme et al.
13 citations
The dynamic core hypothesis posits that consciousness is correlated with simultaneously integrated and differentiated assemblies of transiently synchronized brain regions. We represented time-dependent functional interactions using dynamic brain networks and assessed the integrity of the dynamic core by means of the size and flexibility of the largest multilayer module. As a first step, we...
Physical review. E
July 28, 2021
Yonatan Sanz Perl, Hernan Bocaccio, Carla Pallavicini et al.
82 citations
The cognitive functions of human and nonhuman 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 equilibrium. We confirmed this hypothesis by investigating electrocorticography data from nonhuman primates undergoing different states of unconsciousness (sleep, and...
bioRxiv (Cold Spring Harbor Laboratory)
July 4, 2021
Gustavo Deco, Yonatan Sanz Perl, Jacobo Sitt et al.
16 citations
preprint
Abstract The complex intrinsic and extrinsic forces from the body and environment push the brain into non-equilibrium. The arrow of time, central to thermodynamics in physics, is a hallmark of non-equilibrium and serves to distinguish between reversible and non-reversible dynamics in any system. Here, we use a deep learning Temporal Evolution NETwork (TENET) framework to discover the asymmetry...
Journal of Psychedelic Studies
May 6, 2021
Federico Cavanna, Carla Pallavicini, Virginia Milano et al.
31 citations
Abstract Background and aims The COVID-19 pandemic and its consequences represent a major challenge to the mental health and well-being of the general population. Building on previous work on the potential long-term benefits of psychedelics, we hypothesized that lifetime use of these drugs could be linked to better mental health indicators in the context of the ongoing pandemic. Methods Two...
bioRxiv Preprint Server
March 11, 2021
Enzo Tagliazucchi, Federico Zamberlán, Federico Cavanna et al.
3 citations
preprint
N,N-Dimethyltryptamine (DMT) is a classic psychedelic capable of inducing short-lasting but profound changes in consciousness. As with other psychedelics, the experience induced by DMT strongly depends upon contextual factors, yet the neurobiological determinants of this variability remain unknown. We combined wireless electroencephalography and source imaging to map changes in neural...
J Psychopharmacol
February 10, 2021
Carla Pallavicini, Federico Cavanna, Federico Zamberlán et al.
73 citations
BACKGROUND: N,N-dimethyltryptamine is a short-acting psychedelic tryptamine found naturally in many plants and animals. Few studies to date have addressed the neural and psychological effects of N,N-dimethyltryptamine alone, either administered intravenously or inhaled in freebase form, and none have been conducted in natural settings. AIMS: Our primary aim was to study the acute effects of...
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...
Conscious Cogn
December 8, 2020
Camila Sanz, Carla Pallavicini, Facundo Carrillo et al.
34 citations
Serotonergic psychedelics have been suggested to mirror certain aspects of psychosis, and, more generally, elicit a state of consciousness underpinned by increased entropy of on-going neural activity. We investigated the hypothesis that language produced under the effects of lysergic acid diethylamide (LSD) should exhibit increased entropy and reduced semantic coherence. Computational analysis...