Journal of Neuroscience
September 18, 2013
Matthew J. Brookes, David Errtizoe, Ben Sessa et al.
501 citations
Psychedelic drugs like psilocybin produce profound changes in consciousness by desynchronizing ongoing oscillatory rhythms in the cortex. Using magnetoencephalography in healthy participants, psilocybin reduced spontaneous cortical oscillatory power from 1 to 50 Hz in posterior association cortices and from 8 to 100 Hz in frontal association cortices, with large decreases in default-mode network areas. Low-level visually induced and motor-induced gamma-band oscillations were unaffected, suggesting some basic oscillatory activity is preserved. Dynamic causal modeling indicated that posterior cingulate cortex desynchronization results from increased excitability of deep-layer pyramidal neurons rich in 5-HT 2A receptors.
Neuroscience of consciousness
January 1, 2021
Lars Sandved-Smith, Casper Hesp, Jérémie Mattout et al.
116 citations
Meta-awareness, the ability to notice the current content of consciousness, is crucial for controlling cognitive states like directing attention. This paper models meta-awareness and attentional control using hierarchical active inference, treating mental actions as policy choices over higher-level cognitive states. A further hierarchical level represents meta-awareness states that modulate the expected confidence in the mapping between observations and hidden cognitive states. Simulations of mind-wandering during a sustained selective attention task illustrate how this inferential architecture enables accessing and controlling cognitive states, offering a computational foundation for a phenomenology of mental action and self-monitoring.
Cerebral Cortex
August 8, 2012
André Schmidt, Andreea O. Diaconescu, Michael Kometer et al.
110 citations
Using dynamic causal modeling and Bayesian model selection on data from a double-blind, placebo-controlled, crossover ketamine study, the authors investigated how the NMDA-receptor antagonist ketamine reduces mismatch negativity (MMN) amplitudes. Guided by a predictive coding framework that unifies adaptation and model adjustment theories, they compared models allowing different expressions of neuronal adaptation and synaptic plasticity. Results replicated that both adaptation and short-term plasticity are necessary for MMN generation. Ketamine significantly affected synaptic plasticity but not adaptation, with a selective effect on the forward connection from left primary auditory cortex to superior temporal gyrus. This model-based estimate of ketamine's effect on synaptic plasticity correlated with ratings of ketamine-induced impairments in cognition and control, suggesting a concrete mechanism linking ketamine effects on MMN to drug-induced psychopathology.
NeuroImage Clinical
August 22, 2015
Rainer Kraehenmann, André Schmidt, Karl Friston et al.
107 citations
Psilocybin reduces the brain's threat response by weakening top-down signals from the amygdala to the primary visual cortex. Using dynamic causal modeling of fMRI data, researchers found that psilocybin decreased the threat-induced modulation of this specific connection within the visual-limbic-prefrontal network. This neural mechanism may help explain how psilocybin shifts emotional processing away from negative toward positive stimuli, which could be relevant for treating mood and anxiety disorders.
Neuropharmacology
December 27, 2022
Robin Carhart‐Harris, Shamil Chandaria, David Erritzøe et al.
106 citations
A theoretical model proposes that psychopathology arises from a defensive process called canalization, which narrows an individual's range of thoughts, feelings, and behaviors by increasing precision or reducing variance in neural responses. This contrasts with an early form of plasticity, TEMP (Temperature or Entropy Mediated Plasticity), which increases variance and learning rate. Canalization entrenches pathology as the agent develops expertise in their disorder, while TEMP, combined with gentle psychological support, may counter this entrenchment. The model distinguishes adaptive from maladaptive canalization and suggests concrete experiments to test its hypotheses.
Frontiers in psychology
January 1, 2018
Kenneth Williford, Daniel Bennequin, Karl Friston et al.
85 citations
The Projective Consciousness Model (PCM) combines a projective geometric model of the perspectival structure of conscious experience with a variational free-energy minimization model of active inference, explaining how consciousness serves a cybernetic function: modulating cognitive and affective dynamics to control embodied agents. Projective transformations link geometry and inference, integrating perception, emotion, memory, reasoning, and perspectival imagination to optimize behavior, resilience, and preference satisfaction. The PCM makes empirical predictions, fits a neurocomputational framework, and accounts for pre-reflective self-consciousness, the first-person perspective, the sense of ownership, and social self-consciousness. The authors argue it offers the most complete theory to date of phenomenal selfhood.
Pharmacological Reviews
September 9, 2022
Devon Stoliker, Adeel Razi, Gary F. Egan et al.
83 citations
Classic psychedelics work primarily by binding to serotonergic 5-HT2A receptors, and their agonist activity at these receptors changes synaptic efficacy, profoundly affecting hierarchical message-passing in the brain. This review synthesizes cognitive and neuroimaging evidence showing that psychedelics influence selfhood and subject-object boundaries—a phenomenon called ego dissolution—which may underlie their subjective and therapeutic effects. Because 5-HT2A receptors sit at the apex of the cortical hierarchy, their agonism may powerfully affect sentience and consciousness. Effects can last beyond the pharmacological half-life, suggesting psychedelics promote neural plasticity. Psychologically, they may disarm ego resistance, expanding the repertoire of perceptual hypotheses and enabling alternate pathways for thought and behavior. The authors interpret these effects through hierarchical predictive coding, offering testable predictions about effective connectivity in cortical hierarchies.
Neuroscience and biobehavioral reviews
July 1, 2023
Daniel Collerton, James Barnes, Nico J Diederich et al.
80 citations
Eight distinct models of complex visual hallucinations have been proposed since 2000, each based on different views of brain organization. Researchers from each model group have now agreed on an integrated Visual Hallucination Framework that aligns with current theories of both real and hallucinatory vision. The Framework identifies cognitive systems involved in hallucinations and enables systematic investigation of how hallucination experiences relate to changes in underlying cognitive structures. The episodic nature of hallucinations points to separate factors for their onset, persistence, and end, suggesting a complex relationship between temporary states and long-term traits of hallucination risk. The Framework also suggests new research directions and potential treatments for distressing hallucinations.
Review of philosophy and psychology
January 1, 2022
Maxwell J D Ramstead, Anil K Seth, Casper Hesp et al.
75 citations
A version of neurophenomenology is presented that uses generative modelling techniques from computational neuroscience and biology to formally model descriptions of lived experience from the phenomenological tradition (e.g., Husserl, Merleau-Ponty). The approach, called computational phenomenology, is situated within the broader project of naturalizing phenomenology. Philosophical objections to that project are evaluated, and the generative modelling framework is reviewed. The approach differs from previous uses of generative modelling for consciousness by constructing computational models of inferential or interpretive processes that best explain particular kinds of lived experience.
World psychiatry : official journal of the World Psychiatric Association (WPA)
June 1, 2024
Dan J Stein, Kris Nielsen, Anna Hartford et al.
70 citations
Psychiatric understanding and treatment benefit from integrating both objective facts and subjective values, moving beyond strict scientism toward a softer naturalism. A pluralist approach—embracing ontological, explanatory, and value pluralism—acknowledges the multi-level causal interactions underlying psychopathology and highlights the importance of lived experience and diverse difference-makers in research and practice. Embodied, embedded, and enactive views of the brain-mind offer a conceptual framework for the mind-body problem that clinically integrates cognitive-affective neuroscience with phenomenological psychopathology.
Neuroscience and biobehavioral reviews
September 1, 2025
Ruben Laukkonen, Karl Friston, Shamil Chandaria
17 citations
A theoretical paper proposes that active inference can model consciousness through three conditions: a world model (epistemic field) defining what can be known, inferential competition (Bayesian binding) selecting only coherent inferences that reduce long-term uncertainty, and epistemic depth—a recursive sharing of beliefs throughout a hierarchical system like the brain. This loop allows the world model to know itself non-locally and continuously evidence that knowing, distinct from self-consciousness. The authors formally propose a hyper-model for precision-control whose latent states encode global weighting rules, enacting epistemic agency and flexibility reminiscent of general intelligence. The theory also addresses altered states, meditation, and the full spectrum of conscious experience.
Neuroscience of consciousness
January 1, 2025
Chris Fields, Mahault Albarracin, Karl Friston et al.
6 citations
The free-energy principle (FEP) constrains possible models of consciousness, especially those of attentional control and imaginative experiences like episodic memory and planning. The paper first reviews classical and quantum formulations of the FEP, focusing on multi-component systems where only some parts interact directly with the environment. It discusses internal boundaries structured as Markov blankets, which act as classical information channels. The analysis shows how this framework supports models of attention and imagination, explaining how imaginative experience can use the same spatio-temporal and object-recognition frames as ordinary perception, and how it can be internally generated yet still surprising. The paper concludes with implications for implementation, phenomenology, phylogeny, and the large variability of imaginative experience in humans.
Communications biology
August 13, 2025
Steven Kotler, Michael Mannino, Karl Friston et al.
2 citations
Intuition, often inconsistently defined, is reframed as an evolutionarily grounded pathfinding mechanism that emerges from the brain's optimization of its relationship with the environment. A review of empirical findings identifies relevant brain networks and links intuition to cognitive states like insight. Unsolved problems dynamically alter attractor landscapes, guiding future intuitions. The concept of 'opportunistic assimilation' is explored through nonlinear neurodynamics, and hippocampal sharp wave ripples are identified as potential neural correlates of intuition, given their role in creativity, choice, action planning, and abstract thinking. Two complementary frameworks—the free energy principle and metastable coordination dynamics—together provide a comprehensive neurodynamical account of intuition's neurophenomenology.
PLoS ONE
December 4, 2025
Jonathan Robinson, Andrew W. Corcoran, Christopher J. Whyte et al.
1 citation
Active inference, a framework for modeling how sentient agents behave, is being tested as necessary for changes in conscious content. In an adversarial collaboration, active inference will be contrasted with two other theories that do not require it for consciousness. This study protocol describes an adaptation of the motion-induced blindness paradigm: an active condition where participants direct their gaze toward a target after it disappears from consciousness and report its reappearance, versus a passive condition where participants fixate centrally while the stimulus array moves in a replay of active eye-tracking data. Two experiments will compare target reappearance across conditions to evaluate active inference's contribution to conscious awareness.
arXiv (Cornell University)
May 15, 2026
Jonas Mago, Edmundo Lopez-Sola, Jakub Vohryzek et al.
States of consciousness with minimal phenomenal content, such as those induced by certain meditation practices, show increased brain entropy similar to high-content psychedelic states, challenging the Entropic Brain Hypothesis that links entropy to phenomenal richness. The Complex Brain Hypothesis resolves this by proposing that brain complexity, not entropy, better indexes the richness of experience. Complexity is modulated by the grain of inference the brain uses to resolve uncertainty: fine-grained inference loosens constraints and proliferates content, as in psychedelic states; coarse-grained inference simplifies experience into contentless awareness, as in minimal phenomenal experiences. Both regimes can elevate entropy but differ in phenomenology and perturbational signatures, refining the Entropic Brain Hypothesis and highlighting minimal phenomenal experiences as a test case for computational theories of consciousness.
June 16, 2025
Ruben Laukkonen, Karl Friston, Shamil Chandaria
preprint
A theory proposes that active inference can model consciousness through three conditions: a generative world model (epistemic field) that defines what can be known; inferential competition where only coherent uncertainty-reducing inferences enter the model (Bayesian binding); and epistemic depth, a recursive sharing of beliefs such that the world model knows it exists non-locally. This self-knowing is distinct from self-consciousness. The theory introduces a hyper-model for precision-control across hierarchical inference layers, termed the Beautiful Loop Theory. It offers insights into meditation, psychedelic states, minimal phenomenal experience, and suggests a path toward conscious artificial intelligence.
arXiv Preprint Archive
September 30, 2024
Lancelot da Costa, Anil K. Seth, Karl Friston et al.
A Rosetta Stone hypothesis from predictive processing proposes that beliefs serve as a central hub linking phenomenology, behavior, and neural dynamics. If phenomenology is a function of beliefs, then specific predictions follow for subjective similarity judgments, cognitive metabolic cost, subjective cognitive effort, and time perception. The connection between beliefs and neural dynamics completes the generative passage for neurophenomenology, while the belief-behavior link is already well-documented. Testing these predictions will inform the validity of the central assumption and advance the neurophenomenology research program.
arXiv Preprint Archive
November 7, 2020
Zakaria Djebbara, Thomas Parr, Karl Friston
Perceptual experience of architecture arises from interactions between the body's sensory and motor systems and the built environment. Actions change perceived surroundings based on expectations shaped by bodily capabilities and architectural features. Affordances—the fit between body structure and movement possibilities in a space—underlie continuous sensory information gathering. This paper takes a first step toward understanding architectural design's role in perceptual experience at a neuronal level, proposing a framework that synthesizes computational neuroscience with architectural phenomenology into a computational neurophenomenology. The framework aims to guide future studies linking architecture and cognitive neuroscience.