Experimental Measurements of Vestibular Hair Bundle Stiffness in the Red Ear Slider Turtle Utricle

dc.contributor.authorSilverman, Jennifer Maryen
dc.contributor.committeechairGrant, John Wallaceen
dc.contributor.committeememberMorris, Don H.en
dc.contributor.committeememberPeterson, Ellengene H.en
dc.contributor.departmentEngineering Science and Mechanicsen
dc.date.accessioned2011-08-06T14:45:39Zen
dc.date.adate2002-08-16en
dc.date.available2011-08-06T14:45:39Zen
dc.date.issued2002-07-31en
dc.date.rdate2003-08-16en
dc.date.sdate2002-08-02en
dc.description.abstractThe ear is the organ used for hearing and maintaining equilibrium. In the inner ear, the vestibular system is responsible for the sense of balance. The main organs of the vestibular system are the semicircular canals, the saccule, and the utricle. Within each of the vestibular organs, sensory receptors in the form of hair cells detect motion and send a message to the brain for interpretation. Hair cells found in different parts of the inner ear are structurally different and are mechanically specialized to perform different functions. In this study, the linear and torsional stiffnesses were measured for hair cells located in the red ear slider turtle utricle. The system used to measure the stiffnesses was composed of a glass whisker (attached to a pipette) used to produce a force on the tip of the bundle, an extrinsic Fabry-Perot interferometer (EFPI) to measure the displacement of the pipette, and a photoelectronic motion transducer (PMT) to measure the displacement of the bundle. Using the measured values of whisker stiffness, whisker displacement, and bundle displacement, the stiffness of the bundle was calculated using statics. For each bundle tested, the location of the bundle was determined by measuring its position from a landmark in the utricle, the line of polarity reversal, characterized by a 180o change in direction of the hair bundles. Stiffness results showed that the linear stiffness of a bundle increased in the area surrounding the line of polarity reversal, otherwise referred to as the striolar region (average linear stiffness of 2.27 E-04 N/m). The average linear stiffness value of bundles found lateral to the striolar region was 6.30 E-05 N/m and in the region medial to the striolar region was 1.16 E-04 N/m. A wide range of linear stiffnesses were found in hair cells medial to the striolar region. There was no correlation found between the torsional stiffness of a bundle and its position and the height of a bundle and its linear or torsional stiffness. As the force applied to a hair bundle was increased, the measured linear stiffness of the bundle also increased.en
dc.description.degreeMaster of Scienceen
dc.format.mediumETDen
dc.identifier.otheretd-08022002-150054en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-08022002-150054en
dc.identifier.urihttp://hdl.handle.net/10919/9705en
dc.publisherVirginia Techen
dc.relation.haspartthesis.prn.pdfen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjecthair cellen
dc.subjectvestibular systemen
dc.subjectutricleen
dc.subjectstiffnessen
dc.titleExperimental Measurements of Vestibular Hair Bundle Stiffness in the Red Ear Slider Turtle Utricleen
dc.typeThesisen
thesis.degree.disciplineEngineering Science and Mechanicsen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
thesis.prn.pdf
Size:
3.54 MB
Format:
Adobe Portable Document Format

Collections