Design and implementation of an FPGA-based embedded system for the automatic adaption of cochlea implants


The goal of this project is to develop a system that allows for the dynamic, in-situ adaptation of cochlea implants. This system is based on a neurological effect also known as the stapedius reflex. This reflex is the brain's response to very loud sound sources, and constitutes a cochlea protection mechanism: by contracting the stapedius muscle, it increases the damping of the sound signals that travels through the middle ear.


In essence, this project progresses in the following three stages:

  1. Deriving the electrical activity of the stapedius muscle.
  2. Detecting the stapedius reflex by correlating electrical signals and visual observations.
  3. Investigating various adaptation mechanisms that regulate the frequency-specific gain values depending on the overall sound volume, the frequency-specific volume, and the appearance or non-appearance of the stapedius reflex.

In order to allow for systematic research, the final result will be an easy-to-use research-and-development tool.


So far the following results have been achieved:

  1. A small data base of electrical activities which have been derived at the stapedius muscle during surgery.
  2. Development of a first prototype for the processing and filtering of the derived signals.
  3. Development of a first prototypical analysis platform that is based on the graphical user interface library Qt.


Peer-reviewed Conference Papers:

WARMUTH, R., BEHRENS, M., DAHL, R., EHRT, K., PAU, H-W. and SALOMON, R., 2014.  Automatic Detection of the Electrical Elicited Stapedius Reflex by Evaluation of Its Electromyographic Signals Engineering. 6, (4), pp. 169-176, DOI: 10.4236/eng.2014.64020.

WARMUTH, R. and SALOMON, R., 2014. The Stapedius Reflex: Processing ist neuronal activity with a small embedded system. International Joint Conference on Neural Networks (IJCNN). IEEE, pp. 3938 - 3943. DOI: 10.1109/IJCNN.2014.6889848.

WARMUTH, R., BEHRENS, M., DAHL, R., PAU, H-W. and SALOMON, R., 2013. The Stapedius Reflex: Beyond its Visually Observable Binary On/Off Behavior. 16. Jahrestagung, Rostock, Deutschland.

WARMUTH, R., BEHRENS, M., DAHL, R., PAU, H-W. and SALOMON, R., 2012. About Electromyographic Signals and the Automatic Detection of the Stapedius Reflex. Inner Ear Biology.

LÜDER, M., WARMUTH, R., HEINRICH, E., JOOST, R. and SALOMON, R., 2011. SRD - Towards a System for the In-Situ Detection of the Stapedius Reflex. IEEE Symposium Series on Computational Intelligence (SSCI 2011), pp. 29 - 34. ISBN: 978-1-4244-9910-6.

WARMUTH, R., GOLDMANN, S. and SALOMON, R., 2010.  WiiLoc: a Step Towards Efficient Device Identification in Large Office Buildings by Wii-Based Localization. IEEE 14th International Conference on Emerging Technologies and Factory Automation (ETFA 2010), pp. 1-6.


DE 10 2013 214 049.5. Ralf Salomon und Ralf Warmuth. Verfahren und Vorrichtung zur Einstellung mindestens eines Verstaerkungsfaktors. Erteilt am 21.11.2014.