Consciousness When Is It Present and How Would We Know? Testing Measures and Assumptions for Detecting Consciousness Across States and Substrates
Published in PhD Thesis, Institute of Basic Medical Sciences, University of Oslo, 2026
Identifying the presence and level of consciousness in a system—whether human, animal, or artificial—is one of the central problems of both consciousness science and clinical practice. This thesis addresses the problem from two angles: examining the assumptions that underlie common inferences about unconsciousness, and empirically testing whether candidate neural measures possess the properties required to serve as valid consciousness indicators.
The empirical work spans multiple manipulations (general anesthesia, sleep, cognitive load) and biological substrates (humans and rodents), applying a battery of EEG-based complexity, connectivity, and integrated information metrics. Across studies, the thesis builds a case for treating consciousness as a graded, multidimensional phenomenon that resists reduction to simple behavioral or neural proxies.
Conceptually, the thesis argues that prevailing frameworks for consciousness measurement inherit assumptions—particularly about what constitutes “unconsciousness”—that are empirically questionable. It proposes more rigorous operational criteria and situates the empirical findings within contemporary debates between Global Workspace Theory, Integrated Information Theory, and predictive processing accounts.
Supervisor: Bjørn Erik Juel. Defended at the Runde Auditorium, Domus Medica, University of Oslo, March 3, 2026.
Recommended citation: Sevenius Nilsen A. (2026). "Consciousness When Is It Present and How Would We Know? Testing Measures and Assumptions for Detecting Consciousness Across States and Substrates." PhD Thesis, University of Oslo.
Download Paper