Kjetil Falkenberg Hansen - helping the hearing impaired and seeking improved music interfaces
Music is the red thread that runs through Kjetil Falkenberg Hansen’s research, from Norwegian University of Science and Technology to KTH Royal Institute of Technology. At the moment, he is working to help people with cochlear implants to become more proficient in hearing with these aids.
Cochlear implants are small electronic devices surgically implanted to provide those with severe hearing impairments with a sensation of sound, through direct electrical stimulation of the auditory nerve. The devices are becoming very sophisticated, but since their resolution in frequency is still modest, users may find them less than pleasant to listen to.
"The music I’m talking about here is not of the melody-based, pleasant sounding sort that people often think of, and it does not have to be", says Hansen.
Instead, he works mostly with computer-generated sounds such as drum loops, noise and sweeping sounds. The sounds have a broad spectrum to cover the frequency range reproduced by the cochlear implants, and to compensate for the problems with discriminating melodies. The character of the computer-generated sounds is useful for determining which sounds are more comfortable to listen to, especially when working with children that have limited communicative abilities.
"For persons who are unused to hearing, the sheer exposure to sound can be overwhelming", he says. "Many deaf-born children have gone months or maybe years without any auditory stimuli."
With the possibility to control the sound environment, like that devised by Kjetil Falkenberg Hansen, people can practice listening to and interpreting various types of sounds and even use the control for expressive communication just like a musical instrument.
To make matters even more complex, many of the children that he works with have other impairments too, such as blindness or autism.
Using music to enable children with hearing impairments to become more comfortable with their cochlear implants is only an intermediate goal for Kjetil Falkenberg Hansen. His research addresses different aspects of developing expressive music interfaces. In other words, how can we make interfaces that allow the user to be expressive with sound and music in an effective and inclusive way?
Before his doctoral thesis in 2010, Hansen did a Master’s degree in Norway. The topic was Disc Jockey playing techniques, the goal was an analysis of what DJ’s do when they ‘scratch’ the records When he came to KTH Royal Institute of Technology, he was able to set up controlled experiments and work in a more scientific way.
"Making experiments and having a more scientific approach was the fun side of things, and gave me the incentive to start on my doctoral thesis", he says.
The transition from DJ tools to interfaces for the hearing impaired came about in collaboration with a speech therapist in Lund, who suggested that the research results might be applied to instruments for children with cochlear implants.
"In this type of work you have to shed your prejudiced ideas about what music is supposed to sound like", says Kjetil Falkenberg Hansen, while he plays some of the computer generated sounds used in his research.