Abstract
Word recognition in noisy situations using linear and non-linear hearing aids was evaluated in subjects with mild and moderate sensorineural hearing loss. First of all, the experimental conditions were established in free-field for fifteen normal hearing listeners. The investigated conditions were composed of the following items; the sound pressure level of signal and noise, the sources of noise (white noise and weighted noise), and the azimuth of loudspeakers (front, right and rear sides) in a free-field. As a result, the signal noise ratios were +10dB and +5dB, the weighted noise was suitable, and the front and right sides were appropriate for the position of the loud speakers. Next, ten mild and moderate sensorineural hearing loss patients with one linear hearing aid and two non-linear hearing aids underwent a word recognition evaluation under these same conditions. The word recognition score with non-linear hearing aids tended to better than with linear ones. Especially, the non-linear hearing aid using a full dynamic compression function demonstrated the best results for patients in which the dynamic range was narrow.
