title: A spatially collocated sound thrusts a flash into awareness.
abstract: To interact effectively with the environment the brain integrates signals from multiple senses. It is currently unclear to what extent spatial information can be integrated across different senses in the absence of awareness. Combining dynamic continuous flash suppression (CFS) and spatial audiovisual stimulation, the current study investigated whether a sound facilitates a concurrent visual flash to elude flash suppression and enter perceptual awareness depending on audiovisual spatial congruency. Our results demonstrate that a concurrent sound boosts unaware visual signals into perceptual awareness. Critically, this process depended on the spatial congruency of the auditory and visual signals pointing towards low level mechanisms of audiovisual integration. Moreover, the concurrent sound biased the reported location of the flash as a function of flash visibility. The spatial bias of sounds on reported flash location was strongest for flashes that were judged invisible. Our results suggest that multisensory integration is a critical mechanism that enables signals to enter conscious perception.
authors.affiliation: Computational Cognitive Neuroimaging Laboratory, Computational Neuroscience and Cognitive Robotics Centre, University of Birmingham Birmingham, UK.
authors.forename: Máté
authors.initials: M
authors.lastname: Aller
authors.affiliation: Max Planck Institute for Biological Cybernetics Tübingen, Germany.
authors.forename: Anette
authors.initials: A
authors.lastname: Giani
authors.affiliation: Max Planck Institute for Biological Cybernetics Tübingen, Germany.
authors.forename: Verena
authors.initials: V
authors.lastname: Conrad
authors.affiliation: Max Planck Institute for Biological Cybernetics Tübingen, Germany.
authors.forename: Masataka
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Computational Cognitive Neuroimaging Laboratory, Computational Neuroscience and Cognitive Robotics Centre, University of Birmingham Birmingham, UK ; Max Planck Institute for Biological Cybernetics Tübingen, Germany.
authors.forename: Uta
authors.initials: U
authors.lastname: Noppeney
keywords: attention; audiovisual; awareness; consciousness; multisensory integration; perception; perceptual illusion; ventriloquism