Currently, we are working on computer models of electrically, acoustically and electroacoustically-stimulated auditory system and their evaluation. Topics are: 

• Speech intelligibility of cochlear implant users
• Speech intelligibility for combined electro-acoustical stimulation in binaural and monaural conditions
• Physiology of the interaction between electric and acoustic stimulation
• Interaction between hearing aid algorithms and psychoacoustics as well as speech intelligibility.

Four audio examples are shown on the right for the presentation of our several possible simulations. They let you experience the hearing with a cochlear implant (CI) or with a hybrid device (low frequencies go to the hearing device at the ear canal, high frequencies to the CI) which is called electro acoustic stimulation (EAS).

Listen to the examples in the following order:
1. CI-Simulation
2. the low frequency part of the signal (please make your speakers as loud as possible)
3. the EAS-Simulation
4. the original sentence.

Could you understand the german sentence "Das Pferd frisst keinen Gurkensalat" right at the first example? All simulations were created through signal processing using scripts and functions by MATLAB from The MathWorks, Inc. The so called vocoder is responsible for the signal processing and the alteration of the signal. The CI-Vocoder was and is further developed at the University of Oldenburg. For a detailed explanation of the CI-Vocoder in the context of the master's thesis by Timo Bräcker click here.

If you want to test the CI-Vocoder, you can download it here. The only necessary software you need is a MATLAB distribution.