Bayesian inference explains perception of unity and ventriloquism aftereffect: identification of common sources of audiovisual stimuli.
We study a computational model of audiovisual integration by setting a Bayesian observer that localizes visual and auditory stimuli without presuming the binding of audiovisual information. The observer adopts the maximum a posteriori approach to estimate the physically delivered position or timing of presented stimuli, simultaneously judging whether they are from the same source or not. Several experimental results on the perception of spatial unity and the ventriloquism effect can be explained comprehensively if the subjects in the experiments are regarded as Bayesian observers who try to accurately locate the stimulus. Moreover, by adaptively changing the inner representation of the Bayesian observer in terms of experience, we show that our model reproduces perceived spatial frame shifts due to the audiovisual adaptation known as the ventriloquism aftereffect.
Sato
Yoshiyuki
Y
Department of Complexity Science and Engineering, Graduate School of Frontier Sciences, University of Tokyo, Tokyo 277-8562, Japan. yoshi@sat.t.u-tokyo.ac.jp
Toyoizumi
Taro
T
Aihara
Kazuyuki
K
D000161:Acoustic Stimulation; D000222:Adaptation, Physiological / Q000502:physiology; D000465:Algorithms; D001499:Bayes Theorem; D002540:Cerebral Cortex / Q000502:physiology*; D003198:Computer Simulation; D006801:Humans; D007088:Illusions / Q000502:physiology*; D007600:Judgment / Q000502:physiology; D008959:Models, Neurological; D009949:Orientation / Q000502:physiology; D013017:Sound Localization / Q000502:physiology*; D013028:Space Perception / Q000502:physiology; D013998:Time Perception / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*