Audio interface design as influenced by perception research
Research in “auditory psychophysics” represents the deep-level study of how the physics of sound is represented by our conscious mind.So what does that have to do with interface design?Well… anything that connects to human perception has implications on how we might perceive an interface.Taking the next logical step, modern research on sound perception can, and does, have implications for the next generation of audio interfaces (true for both a complete audio interface such as an automated phone system, or simply the audio aspect of a multi-modal interface such as a cell-phone ring).Examples of this trend can be seen surrounding interface ideas related to hearing loss.
First, let’s target the implications of research and technology geared toward accessibility for those suffering from hearing loss.Hearing aids have participated in an endless struggle with the telephone since their inception.Imagine your phone conversations continually interrupted by the amplified sound of your hearing aid bumping against your telephone.This is only one of many accessibility problems for hearing aid users.This problem multiplies in severity when compounded with the inability of microphones to distinguish relevant sounds from background noise (a factor which has expanded with the advent of using cell-phones in public places).So who has the answer?… Nokia does, with their Wireless Loopset. This exceptional device is sure to be the first of a series of accessible solutions. The Loopset uses BlueTooth technology to actually turn your hearing-aid into your cell-phone headset, an elegant and complete solution.
Another demonstration concerns a condition known as presbycusis: a loss of sensitivity to high-frequency sound that emerges with age. In general, the older you get, the more difficulty you have hearing high-pitched noises. The condition emerges from the degeneration of certain neural receptors in the cochlea (a hydraulic pump within your ear designed to separate complex sounds into their individual components). The first “researchers” to jump on adopting interface implications from this were, in fact, young British students with mischievous intentions. It’s really quite brilliant; students configured their cell-phones to play an extremely high frequency ringtone (named ‘Mosquito’ in its original implementation by a Welsh security company). Ironically, this tone was first designed to disperse loitering teenagers while leaving adults unaffected. In this case, however, older professors could not detect the sound of their students text-messaging each other across the room. This anecdote raises two open questions:
- How could we use this principle in a commercially viable device?
- Are you young enough to hear the sound?