“Young” and “Old” Voices: the prosodic auto-transplantation technique for speaker’s age recognition

The present study is intended to figure out the extent to which prosody and intonation affect listeners’ ability to estimate the speaker’s age. The performance of a 40-year old anchorman and another by the same speaker at the age of 80 were spectroacoustically analyzed in order to identify the prosodic features of a “young” and an “old” voice. The results of the analysis have shown significant differences between the two voices on a suprasegmental level. To test the effects of these differences on a perceptual level, through the prosodic transplantation technique, the F0 values and the durations of segments and silences were transferred from the “young” to the “old” voice and viceversa. Two age recognition tests, based on original and transplanted voices, were administered to Italian listeners. The results of perceptual tests have confirmed the strict relationship between some rhythmic and prosodic features and the speaker’s age and have demonstrated the effectiveness of the transplantation technique. With advancing age, articulation rate and speech rate slow down, voice register rises and tonal range widens. Moreover, the “old” voice is also characterized by a higher percentage of vocalic portion which determines a shift of the Italian rhythm towards the isomoraic pattern.