Audio / Video

Making an effort to listen

  • 01:13:17


Human hearing is enhanced by an active process that amplifies the ear's mechanical inputs, sharpens frequency discrimination, and compresses six orders of magnitude in the amplitude of sounds into only two orders of magnitude in output. In addition, spontaneous otoacoustic emissions emerge from ears in a very quiet environment, an indication that the active process can be so exuberant as to become unstable. Cooperativity between mechanoelectrical-transduction channels confers negative stiffness on the hair bundle, eliciting a dynamical instability that underlies the active process. Experiments on individual hair bundles have shown that the bundle's operation near this instability, the Hopf bifurcation, accounts for the four characteristics of the active process.



Making an effort to listen


University of California, Berkeley. Dept. of Physics


Berkeley, CA, University of California, Berkeley, Dept. of Physics, March 28, 2016

Full Collection Name

Physics Colloquia






1 streaming video file

Other Physical Details

digital, sd., col.


Physics Library


Recorded at a colloquium held on March 28, 2016, sponsored by the Dept. of Physics, University of California, Berkeley.

originally produced as an .mts file in 2016

Speakers: Hudspeth, Jim.

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Physics Colloquia


colloquia/3-28-16Hudspeth.mp4 01:13:17

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