PSYCH 3A03 Lecture Notes - Sound Energy, Basilar Membrane, Sound

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

Document Summary

Remember that base is always stimulated even though the peak of amplitude may occur ;ater towards apex. Apex is not always stimulated, especially in cases of high frequency where damping can occur. Shows how different frequencies will cause peaks at different locations. Graph is distance from apex (aka backwards from how wave will normally travel) At 27mm, 200hz tone is 180o phase shifted relative to stapes motion. On graph, 200hz lines up to 27mm. On phase graph 27mm lines up to 180o phase shift. Period (t) of 200hz: 1/f, therefore t: 5ms. Therefore, traveling wave takes 2. 5ms to reach 200hz tuned region of basilar membrane. Basal end of basilar membrane vibrates best at high frequencies but also responds to low frequencies. Low frequencies still have to pass basal end to get to apex. Apical end of basilar membrane vibrates only to low frequencies.