The role of 3-canal biomechanics in angular motion transduction by the human vestibular labyrinth

Marytheresa A. Ifediba, Suhrud M. Rajguru, Timothy Hullar, Richard D. Rabbitt

Research output: Contribution to journalArticle

45 Citations (Scopus)

Abstract

The present work examines the role of the complex geometry of the human vestibular membranous labyrinth in the process of angular motion transduction by the semicircular canals. A morphologically descriptive mathematical model was constructed to address the biomechanical origins of temporal signal processing and directional coding in determining the inputs to the brain. The geometrical model was developed based on shrinkage-corrected temporal bone sections using a segmentation/data-fitting procedure. Endolymph fluid dynamics within the 3-canal labyrinth was modeled using an asymptotic form of the Navier-Stokes equations and solved to estimate endolymph and cupulae volume displacements. The geometrical model was manipulated to study the role of major morphological features on directional and temporal coding. Anatomical results show that the bony osseous canals provide reasonable estimates of the orientation of the delicate membranous canals-the two differed by only 3.48 ± 1.89°. Biomechanical results show that the maximal response directions are distinct from the anatomical canal planes, but can be closely approximated by fitting a flat plane to the centerline of the canal of interest and weighting each location along the centerline with the inverse of the cross-sectional area squared. Vector cross-products of these maximal response directions, in turn, determine the null planes and prime directions that transmit the direction of angular motion to the brain as three independent directional channels associated with the nerve bundles. Finally, parameter studies indicate that changes in canal cross-sectional area and shape only moderately affect canal temporal and directional coding, while three-canal orientation is critical to directional coding.

Original languageEnglish (US)
Pages (from-to)1247-1263
Number of pages17
JournalAnnals of Biomedical Engineering
Volume35
Issue number7
DOIs
StatePublished - Jul 2007
Externally publishedYes

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Biomechanics
Canals
Brain
Fluid dynamics
Navier Stokes equations
Signal processing
Bone
Mathematical models
Geometry

Keywords

  • Inner ear
  • Mechanotransduction
  • Sensory
  • Vestibular

ASJC Scopus subject areas

  • Biomedical Engineering

Cite this

The role of 3-canal biomechanics in angular motion transduction by the human vestibular labyrinth. / Ifediba, Marytheresa A.; Rajguru, Suhrud M.; Hullar, Timothy; Rabbitt, Richard D.

In: Annals of Biomedical Engineering, Vol. 35, No. 7, 07.2007, p. 1247-1263.

Research output: Contribution to journalArticle

Ifediba, Marytheresa A. ; Rajguru, Suhrud M. ; Hullar, Timothy ; Rabbitt, Richard D. / The role of 3-canal biomechanics in angular motion transduction by the human vestibular labyrinth. In: Annals of Biomedical Engineering. 2007 ; Vol. 35, No. 7. pp. 1247-1263.
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