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bioRxiv Preprint Server

202 papers in the library · 574 citations · publishing 2015-2026

Papers

Ketamine disrupts gaze patterns during face viewing in the common marmoset

bioRxiv Preprint Server February 16, 2021 Janahan Selvanayagam, Kevin D. Johnston, Raymond K. Wong et al. preprint

Faces are critical social signals for primates. The common marmoset is a promising model for studying face processing because its eye-movement and face-processing brain networks resemble those of macaques and humans. Face processing is often disrupted in conditions like schizophrenia. The drug ketamine, which blocks NMDA receptors, is used to model cognitive symptoms of schizophrenia. Four marmosets received either ketamine or saline while watching videos of other marmosets' faces (intact or scrambled). After ketamine, marmosets looked more at the snout than the eyes, and the pattern of where their gaze landed was no longer predictable from where it started, unlike after saline.

Neural Correlates of a Trance Process and Alternative States of Consciousness in a Traditional Healer

bioRxiv Preprint Server January 4, 2021 Rebecca G. Rogerson, Rebecca Barnstaple, Joseph F.x. Desouza preprint

Listening to music while entering a trance state activates specific brain regions. In a traditional South African healer, auditory cortex in both hemispheres showed increased BOLD signal during trance. Right parietal, right frontal, and area prostriata also correlated with trance perception. The orbitofrontal cortex, part of the Default Mode Network, showed reduced activation, especially when trance was high. This pattern suggests a neural signature for trance as a unique altered state of consciousness.

Contemplative mental training reduces hair glucocorticoid levels in a randomized clinical trial

bioRxiv Preprint Server November 13, 2020 Lara M.c. Puhlmann, Pascal Vrtička, Roman Linz et al. preprint

Regular contemplative mental training may reduce long-term stress as indicated by endocrine markers, though the abstract does not specify the direction or magnitude of the effect. The study aimed to investigate how such training influences stress-related hormone levels.

Ketamine increases activity of a fronto-striatal projection that regulates compulsive behavior

bioRxiv Preprint Server July 6, 2020 Gwynne L. Davis, Adelaide R. Minerva, Argentina Lario et al. preprint

Ketamine rapidly reduces compulsive grooming in a mouse model of obsessive-compulsive disorder by increasing activity in a specific brain circuit connecting the dorsomedial prefrontal cortex to the dorsomedial striatum. Optogenetically mimicking this increased fronto-striatal activity also rescued compulsive behavior, while inhibiting this circuit in normal mice increased grooming. These findings suggest this neural pathway may underlie ketamine's fast-acting therapeutic effects in OCD.

Ibotenic acid biosynthesis in the fly agaric is initiated by glutamate hydroxylation

bioRxiv Preprint Server November 18, 2019 Sebastian Obermaier, Michael Müller preprint

The fly agaric mushroom produces psychoactive compounds ibotenic acid and muscimol. Fifty years ago, scientists proposed that their biosynthesis begins with 3-hydroxyglutamate. Researchers identified and recombinantly produced a glutamate hydroxylase enzyme from Amanita muscaria that supports this hypothesis. The gene for this enzyme is flanked by six other genes linked to ibotenic acid production based on recent genetic data. These findings offer new understanding of a long-standing question about a drug used for centuries.

Biosynthesis of an Anti-Addiction Agent from the Iboga Plant

bioRxiv Preprint Server May 26, 2019 Scott C. Farrow, Mohamed O. Kamileen, Lorenzo Caputi et al. preprint

The psychoactive plant compounds (−)-ibogaine and (−)-voacangine show promise for treating opioid addiction but are difficult to obtain from natural sources. Researchers report the complete biosynthesis of (−)-voacangine and its de-esterified form, which can be converted to (−)-ibogaine by heating. This discovery enables production of these compounds through synthetic biology. Notably, these compounds have the opposite enantiomeric configuration compared to other major alkaloids in their class. The identification of the biosynthetic enzymes reveals how nature produces both enantiomeric series of this medically important alkaloid scaffold using closely related enzymes, including those that catalyze enantioselective formal Diels-Alder reactions.

A human intracranial map of consciousness returning from anesthesia

bioRxiv Preprint Server June 17, 2026 Xinyu Chen, Haoru Zhang, Xinran Deng et al. preprint

Consciousness re-emerges from propofol-induced general anesthesia through a multiscale reorganization of brain activity, not a single event. Anesthesia is an organized low-frequency regime with aperiodic slow waves, alpha/beta rhythms, global alpha synchronization, and phase-amplitude coupling. After anesthetic cessation, this regime dissolves as neural excitability and complexity increase. Conscious behavior returns with a rapid transformation in high-gamma activity, shifting from random bursts to structured, task-selective, event-locked responses. The findings chart an electrophysiological map of how conscious cognition is extinguished, reconfigured, and restored in the human brain.

A Shared Entropic Axis Spans States of Consciousness Across Pharmacological and Clinical Conditions

bioRxiv Preprint Server June 12, 2026 Dante Sebastián Galván Rial, Gabriel A. Della Bella, Lorina Naci et al. preprint

States of consciousness can be ordered along a single dimension defined by the entropy of spontaneous neural activity, as proposed by the Entropic Brain Theory. Applying the same analytical pipeline to pharmacological (psychedelics, modafinil, propofol anaesthesia) and clinical (schizophrenia) fMRI datasets, the temporal irregularity of brain network topology was quantified. Propofol anaesthesia occupied the low-entropy end; psychedelic states and schizophrenia occupied the high end. This ordering tracks combined modulations of the level and content of consciousness, from reduced awareness under anaesthesia to heightened arousal and expanded experience under psychedelics and disorganised processing in schizophrenia. The result was not reducible to fluctuations in mean functional connectivity and was supported by convergent reorganisation of higher-order association cortex.

The blueprint of human functional architecture shifts from cognition to anatomy during perturbations of consciousness

bioRxiv Preprint Server June 7, 2026 Andrea I. Luppi, Dragana Manasova, Justine Y. Hansen et al. preprint

Functional connectivity in the awake human brain is shaped primarily by cognitive co-activation—the tendency of brain regions to work together during mental tasks—more than by structural or molecular constraints. This predominance is systematically lost across five datasets involving pharmacological and pathological perturbations of consciousness (chronic disorders of consciousness; anesthesia with sevoflurane, propofol, or ketamine), when cognition is disconnected from the environment or abolished. During such states, the predictors of functional architecture shift away from cognitive co-activation and toward anatomical and molecular constraints.

RIFT: A Fractal-Holographic Theory of Consciousness and Autopoietic Control

bioRxiv Preprint Server March 23, 2026 Erhard Bieberich preprint

A new theory, Recurrent Integration Fractal Theory (RIFT), proposes that consciousness is not a mere byproduct of brain activity but a causally effective force. It suggests that consciousness emerges when the brain compresses sensory information into a fractal pattern, creating an internal holographic space—the endospace—where the self perceives the outer world. Through autopoietic feedback, this inner space can then control the molecular substrate from which it arose, making consciousness an active agent rather than an epiphenomenon.

Not all mantra meditations are equal: Emergence of divergent alpha oscillatory dynamics across mantras

bioRxiv Preprint Server February 26, 2026 Angqi Li, Julio Rodriguez-Larios, Mengsen Zhang et al. preprint

Two types of mantra meditation produce distinct brain activity patterns. Novice practitioners were randomly assigned to chant either the Hare Krishna (HK) or Sa-Ta-Na-Ma (SA) mantra. EEG measurements showed that HK meditation led to widespread decreases in alpha power and increases in alpha frequency during and after practice, suggesting a more activating, attentionally focused state. In contrast, SA meditation produced localized alpha power reduction and, after training, a significant decrease in alpha frequency, indicating a more relaxed state. Both groups reported reduced stress. These results challenge the idea that all mantra meditation is the same and underscore the need to differentiate practices for targeted mental health applications.

Automatic binding of basic sensory features requires consciousness

bioRxiv Preprint Server December 10, 2025 Zhili Han, Hao Zhu, Qian Chu et al. preprint

Conscious awareness is needed for integrating basic sensory features into coherent percepts. Using intracranial recordings in awake and anesthetized states, the study found that in the awake state, the brain automatically encodes individual auditory features (loudness and tone) and binds them together without attention, within a localized sensory cortical network. In the anesthetized state, encoding of single attributes is preserved, but binding is abolished, and anesthesia mainly affects later cortical processes after stimulus offset. These results suggest the functional boundary of consciousness lies between encoding and manipulation of basic sensory features at local cortical circuits, rather than global computations.

Thermodynamics of consciousness: A non-invasive perturbational framework

bioRxiv Preprint Server December 9, 2025 Tomas Berjaga-Buisan, Juan Manuel Monti, Martina Cortada et al. preprint

A non-invasive framework using generative whole-brain models of non-equilibrium dynamics reveals that violations of the Fluctuation-Dissipation Theorem (FDT) in spontaneous brain signals are reduced in unresponsive disorders of consciousness and anesthesia compared to conscious states, mirroring patterns seen with the Perturbational Complexity Index (PCI). This links PCI to fundamental physics principles and offers new objective, model-based tools for assessing consciousness loss and recovery.

Analytical meditation improves physiological well-being in expert practitioners: a study on central and peripheral neurophysiological correlates

bioRxiv Preprint Server December 8, 2025 Alejandro Luis Callara, Mohammad Hadi Azarabad, Laura Sebastiani et al. preprint

Advanced meditation in experienced Tibetan monks produces a unique psychophysiological state of relaxed-vigilance, characterized by enhanced parasympathetic tone, decreased respiratory rate, and gradually increasing electrodermal activity—indicating simultaneous calm and alertness. EEG recordings showed elevated gamma-band power during analytical meditations. These findings suggest that advanced meditative practices foster an adaptive integration of autonomic and cortical responses, supporting well-being and cognitive flexibility.

Functional connectivity drifts during sleep as a marker of fluctuations in the level of consciousness

bioRxiv Preprint Server November 14, 2025 João Patriota, Giulia Moreni, Jorge Mejias et al. preprint

Consciousness is thought to fluctuate with the integration of brain areas across the wake-sleep cycle, but recent evidence suggests consciousness may not be uniformly present or absent within a given brain state, as conscious reports can occur during Non-REM sleep. This study tested whether functional connectivity between neurons varies within brain states in a way that reflects changing levels of consciousness. In rats, directed functional connectivity between neurons was examined across the wake-sleep cycle at a scale of a few seconds. The analysis aimed to determine whether Non-REM sleep contains epochs with inter-areal integration comparable to wakefulness and REM sleep, and vice versa. The findings could reveal circuit-level connectivity patterns consistent with alternating levels of consciousness both between and within brain states.

Thalamic oscillations distinguish natural states of consciousness in humans

bioRxiv Preprint Server January 28, 2025 Aditya Chowdhury, Xiongbo Wu, Tara Beilner et al. preprint

A distinct brain oscillation in the 19-45 Hz range, recorded directly from the human central thalamus, is present only during REM sleep and wakefulness and absent during non-REM sleep. This oscillation co-occurs with bursts of eye movements during REM sleep and is specific to the central thalamus, a structure linked to global brain state transitions. The finding provides a new electrophysiological signature that distinguishes conscious states, offering a pathway to investigate thalamic roles in consciousness and potentially refine treatments for disorders of consciousness.

Computational modelling shows evidence in support of both sensory and frontal theories of consciousness

bioRxiv Preprint Server November 2, 2024 Kavindu H. Bandara, Elise G. Rowe, Marta I. Garrido preprint

The prefrontal cortex's role in consciousness is debated: frontal theories say it is necessary, while sensory theories argue consciousness arises from the posterior cortex alone. Re-analyzing EEG data from 30 participants in a no-report inattentional blindness paradigm, dynamic causal modeling estimated effective connectivity between prefrontal and posterior cortices. A data-driven search could not support either theory, but a hypothesis-driven analysis showed both could explain the data, with a slight preference for frontal theories. A model disabling backward connections within the posterior cortex explained awareness better (53%) than one without prefrontal-to-sensory backward connections. The findings suggest a subtle frontal contribution and call for revising current theories.

Neural field theory as a framework for modeling and understanding consciousness states in the brain

bioRxiv Preprint Server October 27, 2024 Daniel Polyakov, P.a. Robinson, Avigail Makbili et al. preprint

Neural field theory (NFT) may serve as a computational framework for representing states of consciousness, though its parameters' connection to consciousness levels is not yet clear. Prior work has shown NFT can distinguish normal from pathological consciousness states.

Neural Correlates of the Embodied Sense of Agency

bioRxiv Preprint Server September 6, 2024 Amit Regev Krugwasser, Reina Van der Goot, Geffen Markusfeld et al. preprint

A reduction in the sense of agency—the feeling of being in control of one's own actions—is linked to decreased attenuation in the alpha frequency band and increased power in the theta frequency band of brain activity. Using electroencephalography and a virtual reality paradigm where visual feedback of a finger movement was altered, trials with sensorimotor alterations could be decoded from brain signals with up to 68% accuracy starting around 200 milliseconds after movement onset. Cross-decoding analyses revealed similar neural patterns for reduced agency in both anatomical and spatial alteration conditions starting around 500 milliseconds. These findings support a two-level formation of the sense of agency: an early, domain-specific implicit component and a later, domain-general explicit component.

Transition to chaos separates learning regimes and relates to measure of consciousness in recurrent neural networks

bioRxiv Preprint Server May 15, 2024 Dana Mastrovito, Yuhan Helena Liu, Lukasz Kusmierz et al. preprint

The critical coupling strength that separates chaotic from ordered dynamics in recurrent neural networks also differentiates two learning strategies: networks initialized with low coupling learn rich representations, while those with larger variance learn lazier solutions. Training moves both stable and chaotic networks closer to the edge of chaos. Biologically realistic connectivity fosters stability across a wide range of variances. The transition to chaos is reflected in the perturbational complexity index (PCIst), a measure that clinically discriminates levels of consciousness. Networks with high PCIst exhibit stable dynamics and rich learning, suggesting a consciousness prior may promote rich learning. The results indicate a relationship between critical dynamics, learning regimes, and complexity-based measures of consciousness.

Criterion placement threatens the construct validity of neural measures of consciousness

bioRxiv Preprint Server February 22, 2024 Johannes J. Fahrenfort, Philippa A. Johnson, Niels A. Kloosterman et al. preprint

Conservative criterion placement in subjective awareness judgments inflates neural effect sizes for both conscious and unconscious processing, while liberal placement reduces them. Simulations and two EEG studies show that the commonly used Perceptual Awareness Scale does not protect against this confound. The findings indicate that response criterion placement threatens the construct validity of neural measures of consciousness.

Short-Term Meditation Training Alters Brain Activity and Sympathetic Responses at Rest, but not during the meditation

bioRxiv Preprint Server December 1, 2023 Anna Rusinova, Maria Volodina, Alexei Ossadtchi preprint

Meditation is widely used for well-being, but it is unclear how quickly physiological changes appear in non-devoted practitioners. This work asks whether changes during meditation can be observed and used with biofeedback or neurofeedback to improve training outcomes.

Neural entrainment induced by periodic audiovisual stimulation: A large-sample EEG study

bioRxiv Preprint Server October 25, 2023 Joel Frohlich, Ninette Simonian, Grant Hanada et al. preprint

Stroboscopic or flicker stimulation, which induces geometric hallucinations through closed eyelids, can entrain neural activity at specific frequencies. In a large sample of over 80 participants per condition, EEG recordings showed that multimodal stimulation combining two visual strobe frequencies with binaural beats produced powerful neural entrainment at the slower strobe frequency, resembling effects of conventional non-invasive brain stimulation. This was compared to sham stimulation with very low strobe frequencies and no binaural beats, and to a control group practicing eyes-closed meditation. The findings suggest stroboscopic stimulation warrants further development as a potential therapeutic technique for psychiatric disorders.

Sustaining wakefulness: Brainstem connectivity in human consciousness

bioRxiv Preprint Server July 13, 2023 Brian L. Edlow, Mark Olchanyi, Holly J. Freeman et al. preprint

Consciousness depends on both arousal (wakefulness) and awareness. While cortical networks for awareness are well studied, the subcortical networks supporting arousal are less understood. By combining ex vivo diffusion MRI, immunohistochemistry, and in vivo 7 Tesla functional MRI in three human brain specimens, the authors identified a default ascending arousal network (dAAN) in the brainstem, hypothalamus, thalamus, and basal forebrain. They mapped connections within the dAAN and between the dAAN and the cortical default mode network (DMN), suggesting a structural basis for integrating arousal and awareness. The data and methods are released to aid further mapping of human consciousness.

An adversarial collaboration to critically evaluate theories of consciousness

bioRxiv Preprint Server June 23, 2023 Oscar Ferrante, Urszula Gorska-Klimowska, Simon Henin et al. preprint

An open science adversarial collaboration directly juxtaposed Integrated Information Theory (IIT) and Global Neuronal Workspace Theory (GNWT) by investigating neural correlates of visual experience. 256 human subjects viewed suprathreshold stimuli for variable durations while neural activity was measured with fMRI, MEG, and ECoG. Information about conscious content was found in visual, ventro-temporal, and inferior frontal cortex, with sustained responses in occipital and lateral temporal cortex reflecting stimulus duration, and content-specific synchronization between frontal and early visual areas.