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NASA NTRS · 20040112306

Imagining physically impossible self-rotations: geometry is more important than gravity

Creem, S. H.·Wraga, M.·Proffitt, D. R.·Kaiser, M. K.
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Abstract

Previous studies found that it is easier for observers to spatially update displays during imagined self-rotation versus array rotation. The present study examined whether either the physics of gravity or the geometric relationship between the viewer and array guided this self-rotation advantage. Experiments 1-3 preserved a real or imagined orthogonal relationship between the viewer and the array, requiring a rotation in the observer's transverse plane. Despite imagined self-rotations that defied gravity, a viewer advantage remained. Without this orthogonal relationship (Experiment 4), the viewer advantage was lost. We suggest that efficient transformation of the egocentric reference frame relies on the representation of body-environment relations that allow rotation around the observer's principal axis. This efficiency persists across different and conflicting physical and imagined postures.

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NASA Discipline Space Human FactorsNASA Center ARCCognitionSpace PerceptionGravitationSupport, U.S. Gov't, P.H.SMathematicsPostureHumanSupport, U.S. Gov't, Non-P.H.SMaleFemaleAdultVisual Perception

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Creem, S. H., Wraga, M., Proffitt, D. R., Kaiser, M. K.. 2001-08-01. Imagining physically impossible self-rotations: geometry is more important than gravity. https://ntrs.nasa.gov/citations/20040112306

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