How hearing works: auditory hair cells

Hearing relies on a mechanical system that detects nanoscale motion. This video explores how sound is detected and converted into a sequence of electric pulses called action potentials. You’ll see how sound information is encoded and a neural circuit for calculating sound location. Finally, you’ll explore the causes of hearing loss, a hearing test, and how our ears contain amplifiers that can emit sound.

This work is copyright © 2023 by Kerry Kim. All rights reserved. No part of this video can be reproduced or transmitted in any form or by any means without my written permission.
0:00 Introduction
0:57 Sensing nanometers
2:27 Action potentials
5:09 Sound localization
7:26 Hearing loss
9:16 Amplification
11:54 Cells are mechanical

Animations made in Blender. Protein structures were made using @BradyJohnston Molecular Nodes tool:    • Molecular Nodes | Getting Started | B...   .
To learn how to make biochemistry animations in Blender, also see @CGFigures video    • Blender for Scientists - Complete Int...  

3D coordinate files for proteins:
PDB ID: 6BNO (Actin)
Gurel, P.S., Kim, L.Y., Ruijgrok, P.V., Omabegho, T., Bryant, Z., Alushin, G.M. (2017) Cryo-EM structures reveal specialization at the myosin VI-actin interface and a mechanism of force sensitivity. Elife 6 doi: 10.7554/eLife.31125
PDB ID: (Cadherin)
Narui, Y., Sotomayor, M. (2018) Tuning Inner-Ear Tip-Link Affinity Through Alternatively Spliced Variants of Protocadherin-15. Biochemistry 57: 1702-1710 doi: 10.1021/acs.biochem.7b01075
PDB ID: 7LGU, 7LGW (Prestin)
Ge, J., Elferich, J., Dehghani-Ghahnaviyeh, S., Zhao, Z., Meadows, M., von Gersdorff, H., Tajkhorshid, E., Gouaux, E. (2021) Molecular mechanism of prestin electromotive signal amplification. Cell 184: 4669 doi: 10.1016/j.cell.2021.07.034
PDB ID: 1F88 (Rhodopsin)
Palczewski, K., Kumasaka, T., Hori, T., Behnke, C.A., Motoshima, H., Fox, B.A., Le Trong, I., Teller, D.C., Okata, T., Stenkamp, R.E., Yamamoto, M., Miyano, M. (2000) Crystal structure of bovine rhodopsin. doi: 10.2210/pdb1F88/pdb