TY - CONF TI - Top-Down and Multi-Modal Influences on Self-Motion Perception in Virtual Reality AU - Riecke, B. E. AU - Västfjäll, D. AU - Larsson, P. AU - Schulte-Pelkum, J. AB - INTRODUCTION: Much of the work on self-motion perception and simulation has investigated the contribution of physical stimulus properties (so-called bottom-up factors). This paper provides an overview on recent experiments demonstrating that illusory self-motion perception can also benefit from top-down mechanisms, e.g. expectations, the interpretation and meaning associated with the stimulus, and the resulting spatial presence in the simulated envi-ronment. METHODS: Several VR setups were used as a means to independently control different sensory modali-ties, thus allowing for well-controlled and reproducible psychophysical experiments. Illusory self-motion perception (vection) was induced using rotating visual or binaural auditory stimuli, presented via a curved projection screen (FOV: 54x40.5$^\circ$) or headphones, respectively. Additional vibrations, subsonic sound, or cognitive frameworks were applied in some trials. Vection was quantified in terms of onset time, intensity, and convincingness ratings. RESULTS & DISCUSSION: Auditory vection studies showed that sound sources participants associated with sta-tionary acoustic landmarks (e.g., a fountain) can significantly increase the effectiveness of the self-motion illu-sion, as compared to sound sources that are typically associated to moving objects (like the sound of footsteps). A similar top-down effect was observed in a visual vection experiment: Showing a rotating naturalistic scene in VR improved vection considerably compared to scrambled versions of the same scene. Hence, the possibility to interpret the stimulus as a stationary reference frame seems to enhance the self-motion perception, which challenges the pre-vailing opinion that self-motion perception is primarily bottom-up driven. Even the mere knowledge that one might potentially be moved physically increased the convincingness of the self-motion illusion significantly, especially when additional vibrations supported the interpretation that one was really moving. CONCLUSIONS: Various top-down mechanisms were shown to increase the effectiveness of self-motion simulations in VR, even though they have received little attention in the literature up to now. Thus, we posit that a perceptually-oriented approach that combines both bottom-up and top-down factors will ultimately enable us to optimize self-motion simulations in terms of both effectiveness and costs. C1 - Las Vegas, NV, USA C3 - Proceedings of HCI international 2005 CN - 0010 DA - 2005/// PY - 2005 SP - 1 EP - 10 UR - http://en.scientificcommons.org/20596227 KW - POEMS KW - Riecke KW - Riecke_2005 KW - VR KW - VR vection POEMS virtual reality KW - Virtual Reality KW - auditory vection KW - bernhard-riecke KW - conferencePaper KW - conferencePapers KW - higher-level/cognitive influences KW - iSpaceWeb KW - multi-modal vection KW - vection KW - vection methods ER -