PSY-3215 Lecture Notes - Lecture 26: Basilar Membrane, Oval Window, Eardrum
Document Summary
Vibration pattern of 1000 hz goes into auditory canal and hits ear drum which starts vibrating at 1000 times per second. Through the three bones last bone starts moving and vibrating at 1000 times per second. Through the oval window into the fluid filled tubes that start vibrating. Inner ear cells start to move and bend as they are moving through the fluid. This movement causes the auditory receptors to fire. Helmholtz (cid:522)there"s something funny about the shape of the basilar membrane(cid:523) When you unroll the membrane, at the oval window it is narrow (base) and then gets wider (apex) Helmholtz thinks he sees (cid:522)strings(cid:523) going across the membrane and compared it to the inside of a piano. The frequency at which a string vibrates depends on the length of the string and not the force that is placed upon it. Long strings produce low pitches vibrate slow. Short strings produce high pitches vibrate fast.
