SELECTED STORIES
Back issues by year published
2005, 2004, 2003, 2002, 2001, 2000, 1999, 1998, 1997, 1996
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| 1st Among Firsts |
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| State of the Art |
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| The Economic Engine That Could |
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| Between Peace and Terror |
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| The Gift |
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| Dollars and Sense |
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| External Affairs |
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IN NORMAL HEARING, sound waves enter a pea-sized structure, the cochlea. Inside the cochlea, the sound waves stimulate bundles of hair cells, which in turn stimulate auditory-nerve fibers. These fibers send electrical signals to the auditory areas of the cerebral cortex in the brain, which interpret them as particular sounds. Damage to a large number of these hair cells results in a profound hearing loss. The snail-shaped cochlear implant helps to compensate for this by acting in place of the damaged hair cells. When sound waves are delivered to the implant via an external microphone and sound processor, the 24 electrodes in the device stimulate the auditory fibers, delivering the signals to the auditory centers of the brain. — JLE
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