Building a working cochlea

Dr Paul Teal, a senior lecturer in the School of Engineering and Computer Science at Victoria University, is part of an international research team that in 2013 was awarded €2.9 million (NZ$4.5 million) by the European Commission to build a model of the human cochlea – the spiral snail-like chamber located inside the ear that turns sound vibrations into electrical signals that travel along nerves to the brain and allow us to hear.

Measuring the electrical signal inside the cochlea

Dr Teal, the only researcher not from a European university or research organisation, received nearly NZ$188,000 of the funding. He was asked to join the team after his ground-breaking research into better ways of measuring the electrical signal generated inside the cochlea (the cochlear microphonic) gained international attention. This research could ultimately lead to new and improved techniques to assess hearing loss.

A healthy functioning cochlea compresses sound waves that amplify quiet sounds more than loud sounds. Commonly with hearing loss, this compression is degraded. The 3-year project will hopefully provide a 3D model of the physics of motion in a working cochlea. Dr Teal’s input allows electrical components to be added to the model, which would otherwise be only mechanical and acoustic. Once finished, the cochlea model and research will be open source (any researcher can access it) and will form part of the Virtual Physiological Human (VPH) framework, which is developing digital data on the entire human body.

Dispute about how the cochlea works

In a press release from Victoria University, Dr Teal says there is still a lot of dispute about how the cochlea even works. “It’s hard to study because of where it is in the body [buried deep inside the ear] and the complex processes at work.”

“The fact that the data will be open source is important. The VPH framework allows observations made in laboratories all over the world to be included and analysed. The models developed as a result of that will ultimately be able to be matched against data about an individual to find out exactly what is taking place with a patient.”

Dr Teal’s research takes advantage of recent advances in electronics to find ways of collecting an electrical signal directly from the cochlea.

Applications of a working cochlea model

He says the tests currently used to measure hearing loss don’t define the full spectrum of sounds people hear, and the prescriptions given as a result are based on population averages rather than an individual’s condition.

“My vision is that we will one day be able to hook people up to a device that plays them tones and sounds and gives an automatic read-out on the make-up of the hearing aid they need."

“Developing the first full model of a working cochlea will bring us closer to realising that vision.”

As well as cochlea research, Dr Teal is hoping to use his expertise in signal processing to develop less invasive ways of monitoring foetal heart beats and methods of detecting seizures in new-born babies.