PSYC 212 Lecture Notes - Lecture 10: Afferent Nerve Fiber, Inferior Colliculus, Basilar Membrane

• School: McGill University
• Department: Psychology
• Course: PSYC 212
• Professor: Reza Farivar

Document Summary

Overview: mechanical mechanisms of sound transduction (quick review from last class, neural transduction of sound by hair cells, characteristic frequency of hair cells, frequency coding by place and phase-locking, encoding of sound intensity, ascending and descending neural pathways. Figure 5. 18 cross-section of the cochlea: tectorial membrane is attached to hairy cells called hair cells. Figure 5. 20: pivoting creates a shearing force. Figure 5. 19 microscopic view of hair cells: a microscopic view of the hair cells, inner hair cells (bottom, outer hair cells (top 3 rows) Figure 5. 21 close up of hair cells: the hair cells are made up of stereocilia. On each stereocilia there are hundreds of potassium and calcium channels. Rectangle on top: lower portion of potassium = high. Rectangle on bottom: you have a mechanical pulley that is opening the gate potassium goes in cell depolarizes. Inhibiting outer hair cells reduces the movement of the basilar membrane.