Physics of Life Reviews
March 1, 2025
Georg Northoff, Andrea Buccellato, Federico Zilio
31 citations
The connection between brain activity and mental experience remains poorly understood. The authors extend their earlier hypothesis that shared temporal and spatial dynamics provide a 'common currency' linking neural and mental features. They present additional evidence from thoughts, meditation, depression, and attention showing that temporal characteristics are shared by both brain and mind. New empirical examples demonstrate that spatial characteristics, such as topographic reorganization, are also shared in depression and meditation. The authors specify distinct forms of temporospatial correspondences along a continuum from simple to complex. They propose an integrated mind-brain theory called the Common currency theory (CCT) as a framework for understanding the neuro-mental relationship.
Physics of Life Reviews
March 1, 2025
Simone Battaglia, Philippe Servajean, Karl Friston
14 citations
The brain's attempt to study itself creates a paradox of self-reference, raising questions about consciousness, psychiatric disorders, and the limits of science. Historically a philosophical issue, modern techniques like functional and structural brain imaging and neurostimulation now allow researchers to probe this inquiry. However, the broader implications remain unclear. The need to use both perception and introspection has led to different formulations of consciousness, and evidence for one does not necessarily support another. Deconstructing this paradox from philosophical and neuroscientific perspectives may yield insights into self-awareness and consciousness.
Physics of Life Reviews
December 1, 2024
Pietro Sarasso, Wolfgang Tschacher, Félix Schoeller et al.
11 citations
Psychotherapeutic change can be modeled using biophysical principles from synergetics and the free energy principle. Introducing sensory surprise into the patient-therapist system may trigger self-organization and the formation of new attractor states, disrupting entrenched patterns of thoughts, emotions, and behaviors. The therapist can facilitate this by cultivating epistemic trust and modulating embodied attention, allowing surprising affective states into shared awareness. Transient increases in free energy enable updates to generative models, expanding the phenomenal field. Increased entropy, complexity, and lower determinism at behavioral and physiological levels are proposed as markers and predictors of therapeutic gains. Future research should explore how the therapist's openness to novelty shapes outcomes.
Physics of Life Reviews
December 1, 2024
Hamutal Kreiner, Zohar Eviatar
9 citations
Inner speech—the silent, internal use of language—is not just about the content of thoughts but also their structure, according to this theoretical paper grounded in embodiment. The authors argue that inner speech simulates the acoustic features of spoken language, especially prosody (rhythm, intonation, and stress), which gives form and structure to thought. This form is essential for mental life, supporting functions like attention, memory, emotion regulation, self-regulation, social conceptualization, and the narrative of self. The paper reviews varieties of inner speech and evidence for its form, concluding that inner speech maintains structural form as a simulation. Future research should explore how this form makes mental processes accessible to conscious thought.
Physics of Life Reviews
March 1, 2025
K Evers, M Farisco, R Chatila et al.
7 citations
A composite, multilevel, and multidimensional model of consciousness is proposed as a heuristic framework for artificial consciousness research. Consciousness is treated as a complex phenomenon with distinct constituents and dimensions that can be operationalized for study and replication. The model avoids binary thinking, such as conscious versus non-conscious, and offers a structured basis for testable hypotheses. Using awareness as a case study, the paper demonstrates how specific dimensions of consciousness can be pragmatically analyzed and targeted for potential artificial instantiation, laying groundwork for advancing scientific and technical understanding.
Physics of Life Reviews
March 1, 2026
Christopher J. Whyte, Andrew W. Corcoran, Jonathan Robinson et al.
5 citations
Subjective experience is multifaceted, making it hard for traditional neuroscientific theories of consciousness to be compared because each focuses on different aspects like perceptual awareness or global states. This work instead starts from active inference, a first-principles framework that models behavior as approximate Bayesian inference, and builds a minimal theory of consciousness from shared features of computational models derived under active inference. By reviewing studies that apply active inference models to consciousness, the authors identify a small set of theoretical commitments implicit in these models, pointing toward a minimal and testable theory of consciousness.
Physics of Life Reviews
January 21, 2026
Zhu-Qing Gong, Xi-Nian Zuo
3 citations
Spontaneous slow oscillations (SSOs) across six frequency bands have a three-layer hierarchical structure that links spectral architecture to functional roles and neurocognitive processes. Commentaries from diverse fields highlight five key themes: how SSOs relate to consciousness, their geometric foundations, evolutionary and metabolic mechanisms, mathematical modeling of traveling waves that generate SSOs, and implications for brain-inspired intelligence. Integrating these perspectives refines the original model and points toward future research directions.
Physics of Life Reviews
March 1, 2026
Robert Chis-Ciure
A commentary argues that a proposed multidimensional heuristic for structuring artificial consciousness research cannot determine whether phenomenal consciousness is nomologically possible in machines. Behavioral-cognitive profiles lack a justified principle linking function to experience, and the awareness case study shows that externally specified goals can produce as-if control rather than original intentionality. The heuristic overlooks that substrate similarity to the adult human brain is currently indispensable for justifiably inferring consciousness. Thus the framework provides a blueprint for a more sophisticated philosophical zombie but cannot tell whether anyone is there.
Physics of Life Reviews
July 1, 2025
Georg Northoff, Federico Zilio, Jianfeng Zhang
The contents of consciousness are shaped primarily through a non-additive pre-post-stimulus interaction that is temporal-dynamic and spatial-topographic in nature. This interaction accounts for the intrinsically subjective nature of conscious experience, which must be distinguished from the more objective modulation by cognitive, sensory, affective, and motor functions. The argument addresses neural features such as alpha power, phase dynamics, trial-to-trial variability, and fractal scale-free dynamics, and relates the approach to other theories like Dendritic Integration Theory, Global Neuronal Workspace Theory, and Integrated Information Theory.
Physics of Life Reviews
July 1, 2024
Georg Northoff, Federico Zilio, Jianfeng Zhang
Conscious perception depends not only on brain activity after a stimulus appears but also on the brain's ongoing, spontaneous activity before the stimulus. Reviewing recent findings, the authors show that pre-stimulus alpha power (a measure of brain oscillations) influences how vividly or confidently people experience a stimulus, while trial-to-trial variability in alpha activity before and after the stimulus shapes conscious content. The key proposal is that pre- and post-stimulus activity interact in a non-additive, not merely additive, way within the alpha frequency band, and this interaction operates across multiple levels from neurophysiology to phenomenology. This perspective aligns with the Temporo-spatial theory of consciousness, emphasizing that understanding consciousness requires examining brain activity across wider timescales.
Physics of Life Reviews
September 1, 2022
Maaneli Derakhshani, Lajos Diósi, Matthias Laubenstein et al.
A critical analysis finds that the Orch OR theory of consciousness, when grounded in the simplest gravity-related dynamical collapse model, is highly implausible. The assessment draws on the newest experimental results from searches for spontaneous radiation predicted by such collapse models, including data from Germanium detectors. The authors examine multiple cases and conclude that the theory does not hold up under these constraints. They discuss the implications of their findings, acknowledge limitations, and outline future plans for developing more realistic gravity-related collapse models.
Physics of Life Reviews
September 1, 2022
Amal Alachkar
Tryptophan, an aromatic amino acid, sits at the center of light-harvesting active sites in proteins from cyanobacteria to higher organisms, suggesting its unique electron resonance delocalization (aromaticity) enabled early photosynthesis. This capacity may have evolved to support more complex functions, including the neural synchronization underlying consciousness. The argument posits that tryptophan's aromatic non-locality could catalyze long-range coherence in neural networks, providing a theoretical basis for defining the neural correlates of consciousness.
Physics of Life Reviews
December 1, 2020
Geraint A Wiggins
The mind/brain operates as an information-processing organ that seeks efficiency by predicting the world to use information efficiently and by regularly re-representing information to store it efficiently. This theory, Information Dynamics of Thinking, is grounded in Shannon's information theory and is designed for computational implementation and empirical testing. The paper reviews background research areas relevant to the theory and discusses its consequences and testable hypotheses.
Physics of Life Reviews
July 1, 2020
G. Northoff, Soren Wainio-Theberge, K. Evers
The brain's spontaneous activity constructs its own inner time and space, and this spatiotemporal dynamics may be the missing link between neural activity and mental phenomena such as self, consciousness, and time perception. The authors propose 'Spatiotemporal Neuroscience,' which focuses on the brain's temporo-spatial dynamics—like functional connectivity and frequency fluctuations—rather than on specific cognitive or affective functions. They show how mechanisms such as spatiotemporal repertoire, integration, and speed give rise to distinct mental features. This approach treats the relationship between neuronal and mental features as intrinsic and non-causal, offering a common currency that connects brain and mind.
Physics of Life Reviews
September 1, 2012
Bernard J Baars, David B Edelman
Consciousness is a distinct kind of brain event arising from massive, parallel interactions in the cortico-thalamic system, not from quantum computations in microtubules. The authors argue that while natural phenomena are reducible to quantum events in principle, quantum-level proposals such as the Orch-OR hypothesis do not explain the prominent empirical features of consciousness, such as its ∼100 ms duty cycle, its role in coping with novel and valued life events, and the fact that many neuronal processes (e.g., vestibular input) never become conscious. They contend that the burden of proof for quantum-level theories has not been met, and no non-biological examples of consciousness are known.