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עבוד אותות במערכת החושים סמסטר א' תש"ע http://www.eng.tau.ac.il/~mira/Senses2009 Virtual Lecture 4. Cochlear model’s geometry. The Cochlear Model Equations: I. Linear Approximation II. OHC are not Active. Frequency Domain Solution. Resonance Frequency.
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עבוד אותות במערכת החושיםסמסטר א' תש"עhttp://www.eng.tau.ac.il/~mira/Senses2009VirtualLecture 4
The Cochlear Model Equations:I. Linear ApproximationII. OHC are not Active
Resonance Frequency Resonance Frequency is obtained at the frequency that yields: Resonance Frequency= Characteristic Frequency
Known Facts & Assumptions • The outer hair cell motility is proportional to the basolateral membrane voltage drop. • The membrane electric analog is a low-pass filter with a cutoff frequency less than 1 kHz. • The capacitance changes with the partition motion. • The current flow through the basolateral membrane is a function of the partition displacement and velocity.
OHC Force γ(x) - is the relative population of OHCs per unit length
OHC Pressure Equation - Substituting the linear approximations in the OHC electrical potential equation yields:
Parameters Estimation For and
WKB Approximation • A1 and A2 are determined by the boundary condition
Cochlear representationsof Chirp Cochlear representation
Cochlear representationsof “SHEN” Cochlear representation
Audiograms CONDUCTIVE HEARING LOSS Sensorineural Hearing Loss
Simulated Audiograms Estimated Loudness: - For Input Signal: Estimated Hearing Level is defined as: