PSYCH101 Lecture Notes - Lecture 8: Basilar Membrane, Spiral Ganglion, Tectorial Membrane

• School: University of Waterloo
• Department: Psychology
• Course: PSYCH101
• Professor: Alan Morgan

Document Summary

Inner hair cells are less numerous (only 3000) but they are the ones doing the job of pitch perception. Outer hair cells (about 12000 per ear) are attached to the basilar membrane, they help lift up the membrane to make its motion more pronounced. Outer hair cells help amplify the sound, inner do pitch perception. Potassium (positive ions) enter the hair cell and depolarize it, hair cells releases neurotransmitter across synapse, signal sent down spiral ganglion. Even though there are few inner hair cells, there s more of type i ganglion, the majority of ganglion are involved in pitch perception. Type ii: connected to outer hair cells. They don t have to send the information very far. Involved in a feedback loop that controls what s going on at the basilar membrane. Send it to part of the brain that is quite nearby, and that part of the brain communicates back telling the hair cells what to do.