The Moon illusion explained by the projective consciousness model. (21st December 2020)

• Record Type: Journal Article
• Authors: Rudrauf, David; Bennequin, Daniel; Williford, Kenneth
• Is Part Of: Journal of theoretical biology. Volume 507(2020)
• Publication Date: 2020-12-21
• Subjects: Consciousness -- Projective geometry -- Free energy -- Perceptual illusions -- The Moon illusion; Biology -- Periodicals; Biological Science Disciplines -- Periodicals; Biology -- Periodicals; Biologie -- Périodiques; Theoretische biologie; Biology; Periodicals; 571.05
• DOI: 10.1016/j.jtbi.2020.110455
• Languages: English
• ISSNs: 0022-5193

Abstract

Highlights: New explanation of the Moon Illusion based on the Projective Consciousness Model. Explanation not susceptible to problems plaguing previous explanations. Model predicts known variations of the illusion and makes other testable predictions. Model predictions supported by experiment carried out in Virtual Reality. Model explains other illusions concerning objects at far and near distances. Abstract: Models of consciousness should account for the phenomenology of subjective experience, including perceptual illusions. The Moon Illusion is a paradigmatic example that has yet to be accounted for. The Moon often appears larger near the perceptual horizon and smaller high in the sky, though the visual angle subtended is invariant. We show how this illusion can result from the optimization of a 3D projective geometrical frame through free energy minimization, following the principles of the Projective Consciousness Model. The model accounts for all documented modulations of the illusion without anomalies (e.g., the "size-distance paradox"), surpasses other theories in explanatory power, makes sense of inter- and intra-subjective variability vis-à-vis the illusion, and yields new quantitative and qualitative predictions. Empirical data from a virtual reality experiment support the predictions of the model. We also discuss how the model suggests explanations for other relevant illusions, concerning objects both at far and nearer distances, including the sky dome illusion, illusions of perceived size observed in the context of crowding experiments, and the Ames Room illusion.