Listening to Music through a Cochlear Implant

Listening to Music through a Cochlear Implant - Part 1

By Mark Ross, Ph.D.

Editor: Cochlear implants (CIs) are changing people's lives every day! Restoring the ability to understand speech for someone who has struggled with that task is often a life-altering experience. And virtually all of the CI users I know are thrilled with their progress. Music is a different matter. Many CI users who hear remarkably well report that music just doesn't sound good. But focused efforts by the CI manufacturers to improve music appreciation is quite recent, and we're starting to hear stories of CI users who once again enjoy music.

Here's Mark Ross with thoughts on his attempts to appreciate music using his relatively recent CI. This article originally appeared in "Hearing Loss" magazine and is reprinted with the author's kind permission.

This is part one of four parts.

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August 2008

My first exposure to music while using my cochlear implant (CI) occurred when I left the NYU Center, right after the implant was activated. It was a cold day in January and I was lucky to find a cab right outside the Center to take me across town. The cabbie might have been the only one in NY whose radio was tuned to a classical music station. A familiar piano piece was being played; it sounded great, and I was thrilled. This, I felt, was another good omen for successful implant use (in addition to being able to somewhat understand the implant audiologist's speech at that initial stage). But since at the time I was mainly focused on understanding the cabbie's speech, I stored the music experience in the back of my mind. This is not to say that I considered the ability to listen to and enjoy music to be unimportant. It is, as a matter of fact, the second most frequently expressed desire among CI recipients. Much of our cultural and social life is bound up in exposure to music.

In the ensuing months I did occasionally listen to music, with rather mixed results I'm afraid. Although I was able to recognize a number of melodies, after a while I essentially stopped listening. I think what happened is that my memory of what music had sounded like pre-implant was just too vivid in my mind; I would play some piece that I recognized and had liked in the past, hear some flat notes or atonal passages, and just quit listening. I liked music too much for too long to have the patience to listen to it being mutilated, or so it sounded to me. So, while I had some "successes" with musical recognition (i.e., in spite of a few discordant notes, I could recognize a number of old favorites), I still considered speech perception to be the primary challenge, and that's what I focused on.

Then it occurred to me that the music I listened to pre-implant, the sounds that I had so much enjoyed over the years, was itself distorted or modified in some fashion. I've worn hearing aids for fifty-six years and except for the last year or so, I've spent my life listening to music (and everything else!) through them. But, clearly, the acoustical elements that I perceived and those that a normal hearing person would perceive could not be the same. The music I was hearing was being delivered to an impaired auditory system by two imperfect hearing aids (and all of them are imperfect to some degree). For example, hearing aids in the early years could not amplify high frequencies very well (3 or 4 KHz was the limit) and up to 10% distortion was considered acceptable (although enough to give an audiophile apoplexy). But still this did not prevent me from obtaining a great deal of pleasure while listening to music. This would be true, to a lesser or greater degree, for every hearing aid user.

What must have been happening is that over the years the musical sounds I heard via my hearing aids became my norm. It was what I was used to; it had evolved into the standard to which I was now comparing the music I heard through the implant. And, right now, the CI fell short. It therefore seemed apparent that a similar developmental process would have to take place with the implant if I were to fully enjoy music again. I needed to find out whether what I heard through the implant could also evolve into some sort of standard, one that provide me with sufficient listening pleasure to make the effort worthwhile. To make this determination, I needed to engage in a personal "musical auditory training" program, one that required a significant time commitment over several months. I'll report on my experiences and impressions in Part 2 of this article in the next issue.

Given that my interest in this topic is both personal and professional, the first steps I took were to examine both the professional literature and the experiences of other implantees. I am far from the only implant user going through this experience and CI manufacturers are well aware of the challenge they face in this respect. By design, CIs were engineered to improve speech perception, not music appreciation. There are significant acoustical differences between speech and music, and processing strategies that are appropriate for one modality may not necessarily work for the other. In fact, while implant users can obtain excellent speech perception scores, their recognition and enjoyment of music still leaves much to be desired. In spite of large individual differences, implant users generally have noted that they have difficulty recognizing and enjoying music. For some implant users, particularly those for whom music had played an important role in their lives, this difficulty is distressing.

To better understand exactly where listening deficiencies occur, researchers have examined the various components of a musical signal, i.e., the beat, rhythm, pitch, timbre, and melody. "Beat" is a steady sound pulse, while "rhythm" is the grouping of beats to create any succession of durations of sound. It is that aspect of the signal that impels people to tap their toes and clap their hands. Research has shown that implant users can perceive the rhythmical patterns of music as well as normally hearing people. So it seems that, at a minimum, people using a cochlear implant can respond to the rhythmical qualities of a musical piece and enjoy and respond to that feature of the music.