Phi fluctuates with surprisal: An empirical pre-study for the synthesis of the free energy principle and integrated information theory.
PLoS Computational Biology October 1, 2023 Christoffer Lundbak Olesen, Peter Thestrup Waade, Larissa Albantakis et al.
Two major theoretical frameworks—the Free Energy Principle, which describes how self-organizing systems maintain order, and Integrated Information Theory, which aims to mathematically characterize conscious experience—are brought together. Analyzing data from an earlier evolutionary simulation, the authors show that agents' surprisal (a measure from the Free Energy Principle) decreases as their fitness and neural integration increase over evolutionary time. Furthermore, surprisal fluctuates in tandem with IIT-based measures of consciousness within individual trials. This suggests that IIT's consciousness measures are partly shaped by the agent's interaction with its environment, making a formal link between the two theories possible.