Visual-Vestibular Fusion for Spatiotemporal Memory and Navigation

We are interested in the basic mechanisms and principles of human navigation. In this project we aim to explore

1) how different sensory modalities, in particular the visual and vestibular system, combine to create a coherent representation of self-motion in space,

2) how perceptions of time and space interact during navigation, and

3) how spatiotemporal working memory is used for goal based navigation.

To answer these questions we employ a combination of psychophysical, functional magnetic resonance imaging (fMRI) and computational modelling techniques. The role of the sensory systems in navigation and spatial orientation is examined experimentally in healthy human subjects, congenitally blind subjects, or subjects with one-sided or bilateral vestibular loss. To reveal the neural basis of path integration, subjects are tested in visual or imagined path integration tasks in an fMRI scanner. The relationship between space and time is investigated using interference tasks, which are known to specifically alter the perception of duration. Our experiments showed that dual-task interference during path integration causes systematic distance errors that are correlated with duration errors. Computational modelling of path integration networks shows that unspecific changes in background firing rate, similar to a cross-modal attentional bias, may explain our findings.

Related Publications

• Deutschländer A, Hüfner K, Kalla R, Stephan T, Dera T, Glasauer S, Wiesmann M, Strupp M, Brandt T. Unilateral vestibular failure suppresses cortical visual motion processing. Brain 131: 1025-1034, 2008
• Seemungal B, Glasauer S, Gresty M, Bronstein A. Vestibular perception and navigation in the congenitally blind. J Neurophysiol 97:4341-4356, 2007
• Hüfner K, Kalla R, Hamilton DA, Stephan T, Glasauer S, Ma J, Brüning R, Markowitsch HJ, Labudda K Schichor C, Strupp M, Brandt T. Spatial memory and hippocampal volume in humans with unilateral vestibular deafferentation. Hippocampus 17:471-485, 2007
• Glasauer S, Schneider E, Grasso R, Ivanenko YP. Space-time relativity in self-motion reproduction. J Neurophysiol 97: 451-461, 2007
• Glasauer S, Brandt T. Non-commutative updating of perceived self-orientation in three dimensions. J Neurophysiol 97: 2958-2964, 2007