Presbycusis and phonemic regression.

One thousand forty two tonal and speech audiograms are compared to the results of Jerger's speech audiometry (Synthetic Sentence Identification). In older subjects (more than 50 years) with a normal PTA or with a high frequency hearing loss, the speech intelligibility is better in a silent than in a noisy environment where it is a function of the Speech reception threshold. This difference is much smaller in younger individuals. In subjects with a horizontal Pure Tone Audiogram (PTA) (between 20 and 60 dB) the speech intelligibility is almost the same in a silent or a noisy environment for both age groups. An important part of phonemic regression in the elderly probably can be explained by pathology of the organ of Corti and the first cochlear neuron.