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Updated: Apr 25, 2026

Cross-Modal Multivariate Pattern Analysis
Published on: November 9, 2011
Against better knowledge: The magical force of amodal volume completion
Vebjørn Ekroll1, Bilge Sayim1, Johan Wagemans1
1Laboratory of Experimental Psychology, University of Leuven (KU Leuven), Tiensestraat 102 - box 3711, 3000 Leuven, Belgium;
Abstract:
In a popular magic routine known as "multiplying billiard balls", magicians fool their audience by using an empty shell that the audience believes to be a complete ball. Here, we present some observations suggesting that the spectators do not merely entertain the intellectual belief that the balls are all solid, but rather automatically and immediately perceive them as such. Our observations demonstrate the surprising potency and genuinely perceptual origin of amodal volume completion.
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