PSYCH 3A03 Lecture Notes - Cochlear Duct, Tectorial Membrane, Psych

• School: McMaster University
• Department: Psychology
• Course: PSYCH 3A03
• Professor: Paul Faure

Document Summary

Cm is a stimulus driven ac potential. Amplitude of cm increases with stimulus and has wide dynamic range, but. Level increases in proportion to basilar membrane motion. Phase difference: travelling wave has to travel from base to apex and depending on the frequencies high frequencies only occurring at the basal turn not the third turn (apex) Frequency of oscillation of cm mirror stimulus. Cm has been used to measure space-time pattern of basilar membrane displacement (i. e. the cochlear traveling wave) Cm can measure the traveling wave of the basilar membrane. Source of cm near boundary of scala tympani and scala media thought to be the movement of ohc stereocilia. Not a true cochlear potential (but is recorded with cochlear electrodes) due to the synchrony of all the nerve fibres exiting the cochlea. Cap is sum of individual action potentials from nerve fibres responding simultaneously. It is a whole nerve compound action potential.