[Hearing impairment in quietude and noise; 2 different forms of expression of presbyacusis].

Many elderly persons have problems in understanding speech in the presence of voice babble, music, etc. Fitting a hearing aid often does not improve their speech intelligibility. For a better insight, we should distinguish between two different modes of presbyacusis. The first mode expresses itself in attenuation of all incoming sounds, which can be compensated successfully by the hearing-aid's electronic amplification. The second mode has to do with a reduced capacity of the ear to separate simultaneous sounds. As the hearing aid amplifies both the wanted and the unwanted sounds, its effect is in this case nihil. Extensive investigations have indicated the extent to which each of the two modes is actually present in the elderly. The data have confirmed that the amplification of the hearing aid cannot solve the hearing problems of the majority of the elderly. They need primarily a hearing aid that would help to separate simultaneous sounds. At the moment, the most promising solution of this difficult technical challenge is improving the directional sensitivity.