Costas Anastassiou
Allen Institute
Integrated information Consciousness is intrinsic causal power, measured as integrated information
Costas Anastassiou is a neuroscientist whose 2011 Nature Neuroscience paper with Rodolfo Perin, Henry Markram, and Christof Koch changed the status of the brain’s electric fields from byproduct to participant. The experiment showed that endogenous field fluctuations, at amplitudes the cortex itself produces, reliably entrain the firing of individual neurons. Ephaptic coupling, coupling through the extracellular field, became a measured property of cortical tissue rather than a theoretical curiosity. The work is examined on this site in the ephaptic coupling analysis, and the 2012 Buzsáki, Anastassiou, and Koch review in Nature Reviews Neuroscience remains the canonical account of where extracellular fields come from.
The program’s 2024 Neuron study refined the result in an important direction. Field entrainment differs by cell class, meaning a shared extracellular field is read with different sensitivity by different neuronal types. A field with structure is a channel with information-bearing capacity, which is exactly the property electromagnetic field theories of consciousness need and which this site treats as measured physics distinct from the theories built on it.
Anastassiou’s contribution to the consciousness debate is therefore foundational rather than ideological. Every field theory, from McFadden’s CEMI account to Susan Pockett’s, depends on fields being causally potent in the brain. The ephaptic literature supplies that dependency’s empirical grounding, and it simultaneously marks the line the theories must not cross without further evidence, since measured coupling does not by itself establish that field information is felt.
Known for. Ephaptic coupling of cortical neurons, endogenous electric fields as causal participants in neural activity, extracellular field biophysics
Coverage on this site
Related researchers
- Larissa AlbantakisUniversity of Wisconsin-Madison, Center for Sleep and ConsciousnessIntegrated Information Theory 4.0 and dissociating intelligence from consciousness in artificial systems
- Anton ArkhipovAllen Institute for Brain ScienceLarge-scale neural simulation, biophysically detailed cortical models, AIBRAIN program, State of Brain Emulation Report 2025
- Bernard J. BaarsThe Neurosciences InstituteGlobal Workspace Theory (GWT), cognitive architecture of conscious access, A Cognitive Theory of Consciousness (1988), In the Theater of Consciousness (1997)
- Adam B. BarrettSussex Centre for Consciousness Science, University of SussexContinuous field formulations of Integrated Information Theory, Measure-theoretic Phi, practical complexity measures, Granger causality
- Melanie BolyDepartment of Neurology, University of Wisconsin-MadisonCo-developer of Integrated Information Theory 4.0 (IIT 4.0), Neural Correlates of Pure Presence, EEG/fMRI consciousness biomarkers, minimal phenomenal experience
- Jakob GarbeNot stated in the paperDOSE-I, the first large public dataset of annotated consciousness transitions during procedural sedation, multimodal biosignal benchmarking
Costas Anastassiou is listed with the other integrated information theorists, who hold that consciousness is intrinsic causal power, measured as integrated information. The theory family behind that position is set out in the index of consciousness theories. Every researcher covered on this site is indexed in the directory of consciousness researchers.