The ageing voice: changes in fundamental frequency, waveform stability and spectrum.

In the present study we searched for age dependent acoustic changes in the voice of 205 men and women divided in four age groups from 60 to 99 years old. Sixty young men and women served as a comparison group. The findings cover three domains of acoustic features. Firstly, the voice pitch of males and females congruate one to another, while range and variability both increase. The values of jitter, shimmer and harmonics-to-noise ratio (measures of microstability of frequency, amplitude and waveform resp.) reflect a growing voice instability. From all spectral characteristics, only the difference between the first and the second harmonic differs significantly when comparing young to old women.