By: Kathleen Faulkner, Aswin Wijetillake, Marianna Vatti, Manuel Segovia-Martinez, Søren Kamaric Riis Research and Technology Development, Oticon Medical
Date: 3 November 2021
There is no doubt that music is an essential part of social life, health, and general well-being – and that substantial research is still needed to give cochlear implant listeners better access to this dimension of life. Music initiates a large range of cognitive processes, it brings forward emotions, memories, associations and makes us synchronize to the beat and makes us want to dance. Music is important for cognitive health – it is “BrainHearing™ 2.0”. We were therefore delighted to bring together researchers, clinicians, surgeons, and people using cochlear implants from across the globe to join forces to bring music to people with cochlear implants at our third International Symposium on Music and Cochlear implants. This bi-annual symposium was conceived by Oticon Medical in dialogue with Prof. Charles Limb, from the University of San Francisco and Assoc. Prof. Jeremy Marozeau from the Danish Technical University. The first Symposium on Music and Cochlear Implants was held at Eriksholm Research Centre in 2016, and the second was hosted by McGill University in 2018, in Montreal.
This year’s symposium was hosted by the Cambridge Hearing Group and was co-funded by the William Demant Foundation and Oticon Medical. The two-day event was held in a hybrid format, with 60 on-site attendees at St. John’s College in Cambridge and more than 300 people joining virtually. This event included talks from world-renowned scientists about cutting-edge research in areas of musical rehabilitation and training, brain hearing, multi-sensory stimulation, and innovative signal processing approaches. An Oticon Medical sponsored session featured our contributions to many of these areas. Oticon Medical got the attention of several of the leading researchers in the field, and the discussion during the symposium about our ongoing research collaborations were fruitful and promising.
A highlight of the event was the CI user panel, led by Prof. Kate Gfeller from the University of Iowa, where CI users shared their personal experiences with music. Oticon Medical sponsored travel grants for these CI users to participate in this discussion. The bi-annual Music and Cochlear Implants symposium is part of our large portfolio within the area of Music and CI. Here we will highlight a few of our key projects focused on Music in CI.
This is a critical interaction because most of us music researchers can’t actually hear the music through a cochlear implant, so we need to interact with them in this community in order to truly understand the problem and what and how we need to fix it.
David Landsberger, New York University School of Medicine.
Feeling the Beat
The Center for Music in the Brain at Århus University and the Institute for Sound and Vibration Research at University of Southampton will explore CI user’s perception of musical rhythm and groove, with and without a wearable electro-haptic device. Since the experience of rhythm is a central part of contemporary music and the basis of how we dance to and socialize through music, the enhancement of rhythm perception could have a substantial impact on CI users’ quality of life. Perception of music and how the brain processes music are central focal points of the study and the dynamic interplay between predictable structures in music and predictive brain processing as a way to better understand the enjoyment of music. This project is part of a large portfolio of research activities we are involved in at Oticon Medical on using additional input modalities, like vibrotactile input, for enhancing CI user’s performance in music listening, sound localization and speech recognition in noise environments. This study is funded by the William Demant Foundation.
Music Training Games
While auditory training may improve music perception skills and music enjoyment, training programs designed for adult CI users are typically not available outside of research protocols. Furthermore, training activities can be rather tedious or boring and many CI users fail to complete them. In Oticon Medical we are working to make music training fun and engaging by developing innovative games focusing on different musical aspects, such as pitch, timbre and harmonicity. During the Oticon Medical sponsored session we presented a sample of the music training games. Our next steps in collaboration with Aalborg University Copenhagen are to develop a variety of different games, trial them with CI users, and explore the potential benefit of including vibrotactile stimulation.
Sound Coding Strategies for Music
The sound coding strategy, which describes the signal processing algorithms the CI system uses to convert sound to electrical stimulation, is integral to a CI user’s perception of complex sounds such as music. At Oticon Medical, we are investigating several concepts for potential next generation sound coding strategies to improve aspects of music perception. We are also striving to find ways to tweak our current strategies to enhance the musical experience of our users. For example, in a research collaboration with Prof. Waldo Nogueira at the Hannover Medical School, we are investigating a new configuration of our current coding strategy that aims to improve enjoyment of popular music. Preliminary results of this joint project suggest patients prefer the updated configuration over the standard configurations.
Optimized Bimodal Fitting
In most geographies, 70-80% of new CI users also wear a hearing aid on their opposite ear. This low frequency acoustic information provides access to cues like pitch and melody that are not well conveyed by the CI alone. However, there is a great deal of variability in bimodal outcomes likely due to the lack of binaural fusion between the electric and acoustic stimulation. In a project funded by the William Demant Foundation, Oticon Medical is working closely with researchers at Hannover Medical School on a project focused on better understanding the fundamental basis for binaural fusion and investigating novel CI fittings aimed to facilitate fusion of the electric and acoustic information. Mismatches between the frequencies allocated to an electrode and the tonotopic frequency of the corresponding electrode may underlie the variability in bimodal benefits for bimodal CI users. Therefore, in partnership with Rigshospitalet in Copenhagen, we are exploring image-guided bimodal fitting using Nautilus to better align the frequency allocation based on the actual electrode position. Individualizing the fitting using the known values of electrode position parameters should provide an increased ability to achieve bimodal fusion which may benefit both speech and music perception.
Improving music encoding and musical enjoyment are critical, and these challenging tasks require substantial research and technology development in the years to come. These projects are part of the department of Research and Technology in Oticon Medical. In R&T we are involved in research and concepts that help to provide the foundation for the next generation of products and services. At Oticon Medical, we are highly determined to bring a better music experience to CI users, because music matters and because sound matters.