Which of the following is true regarding Electrocochleography
High-Yield Explanation
Ans. b. Outer hair cells are mainly responsible for cochlear microphonics and summation potential Outer hair cells are mainly responsible for cochlear microphonics and summation potential. Electrocochleography: ECoG is inner ear (not the middle ear) potential measurement Action potential (AP) is a compound of synchronous auditory nerve potentials AP represents neural potential Electrocochleography Electrocochleography (ECoG) measures the electrical potential arising in the cochlea and the eights cranial nerve in response to auditory stimuli within first few milliseconds Constituents of an ECoG Cochlear microphonic (CM) Summating potential (SP) Compound Action Potential (AP) Generated predominantly the outer hair cells of theorgan of Coi. Generated predominantlyby the outer hair cells ofthe organ of Coi Represents the summed response of thesynchronous firing of several thousandsauditory nerve fibers Reflects predominantlybasal-end cochlear activitywhen recorded from theround window and moreremote sites. ECoG of patients withMeniere's disease/endolymphatic hydropsoften display enlargedSPs Most popular application of the AP involves measurement of its magnitude in comparisonto that of SP in patients suspected of havingMeniere's disease (endolymphatic Hydrops Enlarged SP/AP amplitude ratio to click stimuli