King Chung, Ph.D., CCC-A, FAAA Amplification and Communication Research Lab ACRL

Current Research Areas   Application of advanced hearing aid technologies to enhance cochlear implant performance   Application of advanced hearing aid technologies to create high-tech hearing protectors that can reduce noise level, enhance low-level sounds, and allow communication with peers.

Methodologies 1. Cochlear Implant  Preprocess incoming signal using hearing aids prior to cochlear implant speech processor via:  Recordings on KEMAR  a hearing aid preprocessor 2. Hearing Protector   Measured the effects on noise level when the noise reduction algorithms are implemented in series or in parallel with compression systems.   Record speech in noise materials with and without digital noise reduction algorithms and compare the speech recognition ability of listeners

Recent Results 1. Cochlear Implant  Directional microphones enhanced speech understanding and perceived sound quality  Noise reduction algorithms improved perceived sound quality 2. Hearing Protector   Noise reduction algorithms implemented in parallel with compression system can provide both low level amplification and effective high level noise reduction.   Noise reduction algorithms reduced the level of noise without aversively affecting speech intelligibility in white noise or in environments where the availability of speech cues is higher limited.

Future Directions 1. Cochlear Implant   Test hearing aid preprocessors in real world environments 2. Hearing Protector   Modify hearing aids to become hearing protectors and test their performance in real-world noises   Implement noise reduction algorithms that can be tailor-fit to specific noisy environments and to optimize the noise reduction algorithm performance for effective noise reduction and communication