Assessing morphology and function of the semicircular duct system: introducing new in-situ visualization and software toolbox.
The semicircular duct system is part of the sensory organ of balance and essential for navigation and spatial awareness in vertebrates. Its function in detecting head rotations has been modelled with increasing sophistication, but the biomechanics of actual semicircular duct systems has rarely been analyzed, foremost because the fragile membranous structures in the inner ear are hard to visualize undistorted and in full. Here we present a new, easy-to-apply and non-invasive method for three-dimensional in-situ visualization and quantification of the semicircular duct system, using X-ray micro tomography and tissue staining with phosphotungstic acid. Moreover, we introduce Ariadne, a software toolbox which provides comprehensive and improved morphological and functional analysis of any visualized duct system. We demonstrate the potential of these methods by presenting results for the duct system of humans, the squirrel monkey and the rhesus macaque, making comparisons with past results from neurophysiological, oculometric and biomechanical studies. Ariadne is freely available at http://www.earbank.org.
Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany.|Centre de Recherches sur la Paléobiodiversité et les Paléoenvironnements (CR2P, UMR 7207), Sorbonne Universités-MNHN, CNRS, UPMC-Paris6, Muséum national d'Histoire naturelle, CP38, 57 rue Cuvier, F-75005, Paris, France.
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David
Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany.
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Stoessel
Collège de France, 11 place Marcelin Berthelot, 75231 Paris, France.
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Berthoz
Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany.|Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK.
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Spoor
Université Paris Diderot-Paris 7, UFR de Mathématiques, Equipe Géométrie et Dynamique, Bâtiment Sophie Germain, 8 place Aurélie Nemours, 75013 Paris Cedex 13, France.
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Bennequin
D000818:Animals; D001696:Biomechanical Phenomena; D007758:Ear, Inner / Q000000981:diagnostic imaging; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008253:Macaca mulatta; D010579:Petrous Bone / Q000000981:diagnostic imaging*; D012453:Saimiri; D054776:Semicircular Ducts / Q000000981:diagnostic imaging* / Q000502:physiology; D012984:Software; D055114:X-Ray Microtomography / Q000379:methods*