Responsible: Elisa Pellegrino
Speech segmental and suprasegmental characteristics vary considerably across the life span due to degenerative changes in speech production mechanisms and neuro-muscolar control. Only little is known about age-related rhythmic variability when this is quantified in terms of segmental durational variability. This instead is important to understand in order to delineate between changes due to healthy ageing and those imputable to the insurgence of pathological conditions, which alter the rhythmic organization of speech (e.g. dysarthria). For this project, age-related rhythmic variability is analyzed cross-sectionally in Zurich Gernam and longitudinally in American English.. Cross-sectional research included comparisons of the consonantal and vocalic intervals durational variability in sentence reading between two groups of Zurich German speakers. Group 1: 16 young adults, aged from 18 to 32 years; group 2: 10 older adults, aged from 66 to 81 years. Longitudinal research examined the segmental durational variability of public speeches held by Noam Chomsky, Walter Cronkite and Donald Regan over a time span of about 40-50 years. Results of cross-sectional and longitudinal studies showed that age-related rhythmic variability is largely accountable for by speech rate differences. Rate normalized rhythmic metrics (VarcoC, VarcoV and n-PVI-V) did not differ significantly as a function of the speakers’ age.
Keywords: Ageing, speech rhythm, speech rate, cross-sectional and longitudinal design