Journal of cognitive neuroscience
September 1, 2023
Charlotte Martial, Héléna Cassol, Mel Slater et al.
13 citations
Out-of-body experiences (OBEs) can be partially induced in a virtual reality setup. Seven healthy participants wore a VR headset and saw their virtual body from a ceiling viewpoint; in one condition their real movements were mirrored onto the virtual body, in the other they were not. Participants reported strong sensations of floating and being high up, but only weak to moderate feelings of being out of their body. Brain activity recorded with 128 electrodes showed that these subjective experiences were linked to increased delta and decreased alpha power, reduced theta complexity, and increased beta-2 connectivity, supporting the idea that delta activity plays a prominent role in certain conscious states.
Frontiers in Human Neuroscience
April 28, 2023
Aminata Bicego, Héléna Cassol, Jessica Simon et al.
13 citations
Spiritual beliefs, Openness to experience, and Fantasy proneness are associated with recalling a near-death experience (NDE) or an NDE-like experience (similar phenomenology without a life-threatening context). In a retrospective study of 181 people divided into four groups—NDE experiencers, NDE-like experiencers, controls who faced a life-threatening situation without an NDE, and controls with neither—multivariate logistic regression showed that spiritual beliefs predicted NDE-like recall, while Openness and Fantasy proneness predicted NDE recall. A discriminant analysis using these variables correctly classified only 35% of cases, indicating other factors also play a role.
Chaos An Interdisciplinary Journal of Nonlinear Science
September 1, 2021
Sofía Morena del Pozo, Helmut Laufs, Vincent Bonhomme et al.
13 citations
Consciousness is linked to brain regions that synchronize transiently in ways that are both integrated and differentiated. Using dynamic brain networks from fMRI data collected during deep sleep and propofol anesthesia, this study found that unconsciousness reduced the size and flexibility of the largest spatiotemporal module, identified as the dynamic core. These results support the dynamic core hypothesis of consciousness.
Psychology of Consciousness Theory Research and Practice
June 12, 2025
Etzel Cardeña, Aviva Berkovich‐ohana, Katja Valli et al.
11 citations
A multidisciplinary, international group used taxonomic principles and a modified Delphi method to create a taxonomy of altered states of consciousness based on central phenomenological features. They identified eight distinct states, some with subcategories: proto and transitional, delirium, minimal to no awareness, experiential detachment, enhanced physicality, altered identity, imaginary/fantasy/visionary, and unity/mystical. The authors hope this taxonomy will foster conceptual clarity and stimulate research across specializations, helping reveal what is common and different across triggers and antecedents of altered states, and encouraging phenomenological, psychological, cultural, and neuroscientific understanding.
NeuroImage
September 1, 2024
Charlotte Martial, Andrea Piarulli, Olivia Gosseries et al.
10 citations
During fainting, some people have dream-like experiences with extraordinary, mystical features similar to near-death experiences. In 22 healthy volunteers who fainted under controlled conditions, eight reported such near-death-like features. Their brain activity showed higher electrical activity in delta, theta, and beta2 frequency bands in temporal and frontal regions, including the insula, right temporoparietal junction, and cingulate cortex. The richer the experience, the stronger the activity in these areas. The brains of those with near-death-like experiences also showed more complex, more connected, and more integrated neural networks compared to those without such experiences. These surges of neural activity may mark disconnected consciousness during fainting.
bioRxiv : the preprint server for biology
October 31, 2023
Charlotte Maschke, Jordan O'Byrne, Michele Angelo Colombo et al.
7 citations
preprint
Consciousness may depend on brain activity poised at criticality, a state with optimal computational properties. Electroencephalograms were recorded from healthy, unresponsive volunteers under propofol, xenon, or ketamine anesthesia. Ketamine spared consciousness (vivid dreams), allowing separation of unresponsiveness from unconsciousness. Unconscious states showed a departure from both the edge of activity propagation and the edge of chaos. The perturbational complexity index (PCI), a sensitive consciousness measure, was predicted from these dynamical properties with a mean absolute error below 7%. Results link PCI to criticality and support criticality's role in consciousness.
Frontiers in Neuroscience
February 13, 2024
Benedetta Cecconi, Javier Montupil, Sepehr Mortaheb et al.
6 citations
Disconnected consciousness, where subjective experience persists but is cut off from the external world, often occurs during sleep or sedation but is difficult to study because unresponsive people may still be conscious and amnesia can erase memories of events. This research uses a serial awakening paradigm during mild propofol sedation: participants hear sounds and are interviewed while still sedated to determine whether they are connected or disconnected from the environment, bypassing the need for behavioral responses and amnesia. Functional MRI data reveal neural activity patterns during these states, testing whether sensory disconnection arises at the thalamus or from disrupted information flow to higher brain regions. Slow-wave activity's role is also explored via high-frequency BOLD oscillations. Findings could improve anesthesia monitoring and assessment of patients with reduced consciousness.
Brain sciences
April 4, 2025
Ying Zhao, Anqi Wang, Weiqiao Zhao et al.
5 citations
A neurophysiological biomarker called the spectral exponent (SE), which measures the steepness of the aperiodic (1/f) slope of EEG activity, can help distinguish levels of consciousness in patients with disorders of consciousness (DoC). In a study of 15 DoC patients, 9 conscious brain-injured controls, and 23 healthy controls, narrowband SE (1-20 Hz) differentiated DoC patients from controls and minimally conscious from vegetative/unresponsive states. SE correlated positively with behavioral scores on the CRS-R, particularly the visual subscale. Longitudinal tracking in one patient showed a reduction in SE negativity, flattening of the 1/f slope, and parallel behavioral recovery. The SE offers an objective complement to subjective behavioral assessments.
Neurotherapeutics : the journal of the American Society for Experimental NeuroTherapeutics
April 18, 2025
Alice Barra, Rodrigo Huerta-Gutierrez, Jitka Annen et al.
3 citations
A subset of patients in a minimally conscious state show improved behavioral responsiveness after transcranial direct current stimulation (tDCS) of the left dorsolateral prefrontal cortex, while those who are unresponsive show limited benefit. Among 131 patients, 32% of minimally conscious patients responded to tDCS, compared to 10% of unresponsive patients. A regression model using baseline diagnosis, Coma Recovery Scale-Revised Index, age, sex, and time since injury correctly identified responders 77% of the time. Patients in a minimally conscious state with better cognitive profiles and longer time since injury appear to respond better to tDCS, suggesting they are better candidates for this treatment.
bioRxiv (Cold Spring Harbor Laboratory)
August 19, 2024
Naji Alnagger, Paolo Cardone, Charlotte Martial et al.
3 citations
preprint
Disorders of consciousness, such as unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), have few treatments. Using whole-brain computational models built from individual patients' fMRI and diffusion-weighted imaging data, this virtual clinical trial simulated the effects of LSD and psilocybin. The psychedelics shifted the brains of patients with disorders of consciousness closer to a critical dynamical state, with a larger effect in MCS patients. In UWS patients, the treatment response depended on structural connectivity, whereas in MCS patients it aligned with baseline functional connectivity. These results provide a computational foundation for considering psychedelics in treating disorders of consciousness and highlight the role of computational modeling in drug discovery and personalized medicine.
Research Square
August 8, 2024
Danilo Bzdok, Robin Carhart-Harris, Chloe Savignac et al.
3 citations
Large language models can design, annotate, and evaluate experience dimensions from psychedelic reports, producing over 2 million automatic ratings that discriminate the unique mental effects of 30 psychoactive substances. This approach offers a bottom-up complement to legacy questionnaires for measuring changes in subjective awareness.
Advanced Science
November 20, 2025
Paolo Cardone, Charlotte Martial, Yonatan Sanz Perl et al.
2 citations
Simulated administration of LSD and psilocybin in computational models of patients with disorders of consciousness (DoC), including unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), shifted brain activity closer to criticality—the phase transition between order and chaos. The effect was greater in MCS patients. In UWS patients, the treatment response correlated with structural connectivity, while in MCS patients it aligned with baseline functional connectivity. These results provide a computational foundation for using psychedelics in DoC treatment and highlight the potential role of computational modeling in drug discovery and personalized medicine.
bioRxiv Preprint Server
February 11, 2025
Saketh Malipeddi, Arun Sasidharan, Rahul Venugopal et al.
2 citations
preprint
Meditation alters brain activity, particularly in alpha and theta frequency bands, but most research has focused on average power changes from rest to meditation rather than how quickly these changes emerge. This gap means little is known about the time-to-onset and temporal dynamics of neural shifts during meditation practice.
Frontiers in Neuroscience
January 1, 2018
Rajanikant Panda, Olivia Gosseries, Audrey Vanhaudenhuyse et al.
2 citations
No Summary
PloS one
January 1, 2023
Justine Van de Velde, Katia Levecque, Bert Weijters et al.
1 citation
A six-month meditation practice of five to ten minutes daily improved emotional and physical well-being and prevented the development of cognitive well-being problems among 199 teachers who meditated with their pupils. A control group of 42 teachers showed worsening cognitive well-being over the same period. The effects were strongest for emotional and cognitive well-being and followed a linear trend. The findings suggest that focused attention meditation, a technique used in many mindfulness-based interventions, contributes to the well-being benefits of those interventions. Occupational groups facing emotional, cognitive, or physical well-being issues may benefit from a few minutes of this practice per day.
Frontiers in Neuroscience
January 1, 2018
Héléna Cassol, Arnaud D’Argembeau, Vanessa Charland‐verville et al.
1 citation
No Summary
Communications Biology
June 12, 2026
Saketh Malipeddi, Arun Sasidharan, Bianca Ventura et al.
Advanced meditators from the Isha Yoga tradition report stronger non-dual experiences—where the boundary between self and environment dissolves—during breath-watching meditation compared to novices and meditation-naïve controls. Using EEG-based intrinsic neural timescales (INT), researchers found that across all participants, INTs are longer during internal attention (breath-watching) than during an external cognitive task. However, advanced meditators show similar INT durations between internal and external attention, and this reduced difference correlates with stronger reported non-dual experiences. The findings suggest that similar intrinsic neural timescale durations across internal and external attention may be a neural signature of non-duality.
Neuroscience of consciousness
January 1, 2025
Daniel Polyakov, P A Robinson, Avigail Makbili et al.
Neural field theory (NFT) can model brain activity across different states of consciousness. By fitting a corticothalamic NFT model to EEG data from healthy individuals and patients with disorders of consciousness, researchers identified correlations between NFT parameters and features of both experimental and simulated EEG. These correlations distinguish healthy from impaired consciousness and point to potential physiological biomarkers. The findings clarify how consciousness levels are represented in the NFT framework and highlight its value for in-silico experimentation in consciousness research.
Frontiers in psychiatry
January 1, 2023
Yan Li, Yan Chen, Charlotte Martial et al.
A Chinese version of the Near-Death Experience Content (NDE-C) scale was translated and validated on 79 near-death experience testimonies. The translation used Brislin's back-translation model, and the scale showed good internal consistency (Cronbach's α = 0.846). Confirmatory factor analysis supported the scale's structure. This new Chinese NDE-C scale is now available to screen people who have had near-death experiences or near-death-like experiences (e.g., from meditation) and to quantify their subjective experiences, enabling further research on this phenomenon in Eastern cultural contexts.
bioRxiv Preprint Server
September 28, 2022
Yonatan Sanz Perl, Carla Pallavicini, Juan Piccinini et al.
preprint
Brain states are often described on a single scale from full consciousness to unconsciousness, but this ignores the complex, high-dimensional nature of brain activity. By combining whole-brain modeling, data augmentation, and deep learning, researchers mapped states of consciousness into a low-dimensional space where distances reflect similarities between states. They found an orderly trajectory from wakefulness to brain-injured patients, with coordinates related to functional modularity and structure-function coupling, both increasing as consciousness is lost. Model perturbations provided a geometric interpretation of state stability and reversibility. The work suggests conscious awareness depends on functional patterns encoded as a low-dimensional trajectory within the vast space of brain configurations.
arXiv Preprint Archive
December 19, 2020
Yonatan Sanz Perl, Hernan Bocaccio, Ignacio Perez-Ipina et al.
Consciousness depends on brain activity that is far from thermodynamic equilibrium. Analyzing electrocorticography data from non-human primates during sleep and various anesthetics, and fMRI data from humans during deep sleep and propofol anesthesia, all states of reduced consciousness showed dynamics closer to equilibrium than conscious wakefulness. This was measured by entropy production and the curl of probability flux in phase space. Non-equilibrium macroscopic brain dynamics therefore serve as a robust signature of consciousness, offering a statistical mechanics approach to studying cognition and awareness.
bioRxiv Preprint Server
July 2, 2020
Yonatan Sanz Perl, Carla Pallavicini, Ignacio Pérez Ipiña et al.
preprint
The level of consciousness—how conscious someone is—is often measured by how similar their brain activity is to normal wakefulness. However, this approach misses important information about how stable that state is. Using computer models of the whole brain, the authors show that the stability of a conscious state—how easily it can be disrupted—provides additional, complementary information. They propose a new framework that sorts brain states by both their similarity to wakefulness and their stability, which helps distinguish between different types of unconsciousness: natural sleep, anesthesia, and brain injury. This framework offers a more complete way to characterize and differentiate states of consciousness.
Comput. Methods Programs Biomed.
July 1, 2019
J. R. D. Miras, F. Soler‐Toscano, S. Iglesias-Parro et al.
A measure combining fractal dimensions of brain activity—capturing both integration and differentiation of cortical responses—can distinguish conscious from unconscious states almost perfectly within individuals. In 18 healthy subjects, the Fractal Dimension Index (FDI) derived from high-density EEG after transcranial magnetic stimulation was significantly lower during non-REM sleep and sedation (with xenon or propofol) than during wakefulness. The index reflects how complex and differentiated the brain's spatiotemporal responses are to a perturbation. The findings suggest that tracking fractal dimensions of cortical dynamics offers a way to assess consciousness, with potential clinical applications for detecting awareness in patients.
arXiv Preprint Archive
May 10, 2016
Enrico Amico, Daniele Marinazzo, Carol DiPerri et al.
A new data-driven method, connICA, extracts independent functional connectivity patterns (FC-traits) from brain scans of patients with disorders of consciousness after severe brain damage. Three main FC-traits emerged. The first relates to sedation, overall pathology, and level of arousal. The second reflects disconnection of visual and sensory-motor networks, time since injury, and ability to communicate. The third involves fronto-parietal and default-mode networks and interhemispheric interaction, associated with self-awareness and awareness of surroundings. Each trait represents a distinct functional process linked to degradation of conscious states, clarifying which neural subcircuits are disrupted in severe brain injury.
Trends in Cognitive Sciences
June 1, 2005
B. Baars, Steven Laureys
The authors critique Ned Block's distinction between phenomenological consciousness (what we experience) and access consciousness (information accessible via conscious experiences). They argue that evidence from cognitive neuroscience does not support this division. For instance, visual cortex activity is necessary but not sufficient for conscious visual qualities; without parietal and prefrontal activation, no correlation with consciousness is found. Similarly, when frontoparietal regions are impaired, sensory consciousness is absent despite sensory cortex activation. The authors contend that unconscious brain mechanisms interact with visual cortex to enable visual qualities, and that positing a separate 'access consciousness' is unnecessary. They suggest that what is needed is simply consciously-mediated access to brain capacities, most of which are unconscious.