Transcript Resources - LeeCworkshops

Our Ear Overlooked
 Though
our hearing is FAR more sensitive than our
vision, about 1/3 of our brains are devoted to the
visual cortex, a complexity of dispersed areas
acting together. The fMRI image below shows
both visual and auditory areas.
sight
Reading & Writing
in New Media
CARLETON
We see the world through a
very small window:
wavelengths between 400-700 nanometers (billionths of a meter)
a factor of 2/1 in frequency…
But what exists that we cannot see?
Read “The Damned Thing” by Ambrose Bierce
…but our hearing is VAST:
pressure wavelengths between 20Hz - 20,000Hz, frequency factor of 1000/1
our amazing anatomy:
1-collection
2-amplification
4-relay
3-reception
cochlear
oval window
at stapes
“place theory” of hearing
…the idea that the position of the ‘hair cell’ along the basilar
membrane in the cochlea corresponds to its frequency
response with lower frequencies (20Hz)* detected closer to
the oval window and increasing at regular intervals up to high
frequency sounds (20kHz) detected towards the
round window. The nerve endings in the cochlea convert sound
air-pressure waves into electrical signals for the brain via a
complex shearing motion between the tectorial & basilar
membranes.
* 1 Hertz (Hz) =
1 wavelength =
cochlea:
our spiral sonic receptor
3.5 cm long
30,000 nerve
endings a.k.a.
“hair cells”
wavelengths
of sonic
receptivity
astonishing complexity
Sound must
travel farther
than sight to
reach the
brain.
Our hearing
compared with our fellow inhabitants…
Resources
Berg, Richard E. The Physics of Sound, 3rd edition
Upper Saddle, NJ: Pearson, 2005.
Calvert, J. B. “Hearing and Sound.” 2000. (11/20/08)
http://hyperphysics.phy-astr.gsu.edu/Hbase/hph.html#ahph1
McLuhan, Marshall. Understanding Media (1964) Critical edition
Terrence Gordon, ed. Corte Madera: Gingko Press, 2003.
Nave, Carl R. “Ear and Hearing” Hyperphysics:Sound.
Georgia State University, 2001. (11/20/08)
http://hyperphysics.phy-astr.gsu.edu/Hbase/hph.html#ahph1
Rossing, Thomas D. The Science of Sound, 3rd edition
San Francisco: Addison Wesley, 2002.