Dynamic displacement of normal and detached semicircular canal cupula
Rabbitt, Richard D.
Breneman, Kathryn D.
Yamauchi, Angela M.
Highstein, Stephen M.
MetadataShow full item record
KeywordVestibular; Inner ear micromechanics; Cupula regeneration; Angular motion sensation; Afferent response dynamics
The dynamic displacement of the semicircular canal cupula and modulation of afferent nerve discharge were measured simultaneously in response to physiological stimuli in vivo. The adaptation time constant(s) of normal cupulae in response to step stimuli averaged 36 s, corresponding to a mechanical lower corner frequency for sinusoidal stimuli of 0.0044 Hz. For stimuli equivalent to 40–200 deg/s of angular head velocity, the displacement gain of the central region of the cupula averaged 53 nm per deg/s. Afferents adapted more rapidly than the cupula, demonstrating the presence of a relaxation process that contributes significantly to the neural representation of angular head motions by the discharge patterns of canal afferent neurons. We also investigated changes in time constants of the cupula and afferents following detachment of the cupula at its apex—mechanical detachment that occurs in response to excessive transcupular endolymph pressure. Detached cupulae exhibited sharply reduced adaptation time constants (300 ms–3 s, n = 3) and can be explained by endolymph flowing rapidly over the apex of the cupula. Partially detached cupulae reattached and normal afferent discharge patterns were recovered 5–7 h following detachment. This regeneration process may have relevance to the recovery of semicircular canal function following head trauma.
© 2009 The Authors. This is an open-access article distributed under the terms of the Creative Commons Attribution Noncommercial License. The definitive version was published in JARO - Journal of the Association for Research in Otolaryngology 10 (2009): 497-509, doi:10.1007/s10162-009-0174-y.
Suggested CitationJARO - Journal of the Association for Research in Otolaryngology 10 (2009): 497-509
The following license files are associated with this item:
Except where otherwise noted, this item's license is described as Attribution-NonCommercial 3.0 Unported
Showing items related by title, author, creator and subject.
Arabian Sea mixed layer dynamics experiment : mooring deployment cruise report R/V Thomas Thompson cruise number 46, 14 April-29 April 1995 Trask, Richard P.; Weller, Robert A.; Ostrom, William M. (Woods Hole Oceanographic Institution, 1995-07)This report describes in a general manner the work that took place during the R/V Thomas Thompson cruise number 46 which was the mooring turnaround cruise for the moored array program. A detailed description of the WHOI ...
Cyclic fatigue testing of surface mooring hardware for the Arabian Sea mixed layer dynamics experiment Trask, Richard P.; Weller, Robert A. (Woods Hole Oceanographic Institution, 1995-12)The Arabian Sea is strongly forced by monsoon winds. Surface moorings deployed in the Arabian Sea are exposed to high winds and large waves. The waves, generated by strong wind events, impose a dynamic load on all mooring ...
Chen, Changsheng; Huang, Haosheng; Beardsley, Robert C.; Xu, Qichun; Limeburner, Richard; Cowles, Geoffrey W.; Sun, Yunfang; Qi, Jianhua; Lin, Huichan (American Geophysical Union, 2011-12-10)The unstructured-grid, Finite-Volume Community Ocean Model (FVCOM) was used to simulate the tides in the Gulf of Maine (GoM) and New England Shelf (NES) for homogeneous and summer stratified conditions. FVCOM captures the ...