BIOL 430 Lecture Notes - Lecture 19: Tympanic Duct, Cochlear Duct, Oval Window
Document Summary
Hearing is our perception of mechanical energy carried by sound waves. Sound is the brain"s interpretation of the sound waves that reach the ear. Loudness is an interpretation of intensity, a function of wave amplitude. Sensory (receptor) cells are hair cells in the cochlea ap. Sound waves strike the tympanic membrane and become vibrations. The sound wave energy is transferred to the three bones of the middle ear, which vibrate. The arrangement of the three connected middle ear bones lever that multiplies the force of the vibration so that very little sound energy is lost due to friction. The stapes is attached to the membrane of the oval window. Vibrations of the oval window create fluid waves within the cochlea. The fluid waves push on the flexible membranes of the cochlear duct. Hair cells bend and ion channels open, creating an electrical signal that alters neurotransmitter release.
