Where is Research Headed?
In most cases, the mathematics and science that is taught to high school students is about what we know. They are things that we have already figured out and someone could get the impression that it’s all been done. Calculus itself is 400 years old. Here, we have concentrated on the FFT, which was probably known in the early 1800s, but was rediscovered in 1965 – still a long time ago, at least to today’s high school student. The CI does use other digital processing techniques that are newer, and we have told you that the CI works. Problem solved? – not by a long shot.
We often fail to let students in on the dirty little secret – there is way more stuff that we don’t yet know.
Currently, a primary direction of research in cochlear implants is music appreciation. Understanding speech is a high-level (brain-centered) functionality. Even if we can’t get the nerve stimulus exactly right, the brain can figure out the words. However, pitch and tone are truly generated in the cochlea, and the CI is no match for what evolution has produced. Below is a link to a demo, (from the web site of the House Ear Institute) which shows what music sounds like to a CI user. The file steps through the simulation for 4, 8, 16, and 32 channels before playing the original music. (Recall that current state of the art CI is equivalent to about 16 channels.)
The physiological limitations of the electrode/cochlea interface indicate that the problem will not be solved by adding more electrodes. Researchers are at work on identifying new processing techniques that can enable the CI to better represent music. In other words, they are working on an applied math problem. Likely, someone will identify the creative math solution – a new mathematical discovery – that will make it work. Could it be you?