The Joy of Music with Hearing Implants
Cochlear implant designs have been successful in helping people hear speech, but music has presented manufacturers with greater challenges.
Music is more complex than speech Johanna Boyer, a music topic manager who works for cochlear implant manufacturer MED-EL, and herself a CI user, explains: “Music is much more complex than speech, with a wider range of frequencies and a bigger dynamic range.” MED-EL has worked to create more sophisticated implants using ‘fine hearing’ technology and soft, flexible electrodes to cover the entire cochlea, which results in an enhanced perception of pitch and tone across all frequencies.
Full and accurate representation of music Boyer adds: “With these techniques, cochlear implant users can improve their perception of music, because the musical signal is represented more fully and accurately.” This has enabled MED-EL to address common issues CI users face as they learn to hear again – such as distinguishing between certain individual instruments when several are playing together, or between acoustic and electric sounds. Some individuals have tuning issues. Vocal and instrumental vibrato can also cause CI users difficulty, because the brain struggles to process rapidly varying pitches when it interacts with the implant. University of Washington researchers are also working on techniques to create better designs. Les Atlas, a professor of electrical engineering, believes that the key may be to help them hear speech in noisy settings. His team has developed a new way of processing signals, enabling implant users to distinguish between different instruments and to hear music better. The researchers are also working on techniques to give implant users a better perception of pitch and melody. A team at the University of Southampton, UK called The Music Focus Group, has been examining ways to help people with CIs to get more out of listening to and making music. The team has started an Interactive Music Awareness Programme where “users can download software and carry out exercises on a regular basis so that they can retrain themselves to understand and start enjoying the music,” says Richard Polfreman, Associate Professor of Music and expert on the interface between music and technology.
Music and speech frequencies (Fellbaum, 1994)
Compared with music, speech tends to be well controlled, with well-established and predictable perceptual characteristics. By contrast, music contains much variation and the perceptual requirements can vary, based on the musician and the instrument being played.© Archive
What does music sound like through a cochlear implant? Hearing music through implants will be different for each person. Every person's hearing loss story is different, so is the perception of music after implantation. The brain needs time to (re-)adjust to stimuli and thus needs time to process these. Learning to hear with any cochlear implant takes patience and dedication - but the more the user listens to music, the better it will sound. In a study of music enjoyment, more than 90% of MED-EL recipients reported that music sounds pleasant through their cochlear implant.