Music Through Cochlear Implants
Sam Swiller had hearing problems since as early as he could remember. As an escape, he would listen to loud rock music like AC/DC and Nirvana - music that he could enjoy even without understanding the lyrics. He enjoyed the theory behind music: “the connection between a band and an audience.”
Then in his 20s, his hearing completely vanished. Sam decided to begin using a cochlear implant. It was a shock at first. When the implant was first turned on, he felt as if he was hearing a digitized version of people’s voices. He had to completely readjust to the new way he was hearing the world around him.
The cochlear implant also completely changed his relationship to music. “I started to like a lot more folk music and vocals, “ Swiller stated. This was not necessarily a bad thing, but the shift in musical tastes reveals a limitation of cochlear implants that is currently being investigated.
A cochlear implant bypasses the damaged part of the ear and delivers electrical impulses to the auditory nerve that are sent to the brain. It’s not just an amplifier, like most hearing aids.
Cochlear implants do well at encoding speech so the user can understand it, but they are less advanced when it comes to encoding pitch and timbre in music. This is why cochlear implants sometimes fall short in conveying how certain instruments like the piano really sound, but are more adept at picking up instruments such as drums.
Researchers at the University of Washington are working on software that will help cochlear implants pick up more information about pitch and timbre, which could result in cochlear implant processors that are able to replicate music a bit more precisely.
A recent NPR article on this topic provides simulations that show how music sounds in cochlear implants and gives examples of how it would sound with the new software being developed by Les Atlas at the University of Washington. The article also points out that more improvements in cochlear implants with regard to timbre and tonality will also be useful to people in other countries such as China and Vietnam where tonality is critical to understanding the language.