Age Differences in Sequential Speech Production: Articulatory and Physiological Factors.

Abstract

To explore age differences in speech production in relation to orofacial physiology. Cross-sectional quasi-experimental group study. General community. Physically and cognitively healthy volunteers recruited from the community (N = 30), including 15 young (18-39) and 15 older (66-85) adults. Accuracy and speech rate were calculated during the production of sequences of syllables containing oral vowels, nasal vowels, or both. Lip and tongue muscular strength, muscular endurance, and tactile sensitivity were also measured. Older adults had a slower speech rate than younger adults and greater difficulty articulating nasal vowels. Analyses revealed that age-related decline in lip endurance is associated with decline in accuracy during speech production. Older adults are not just slower than younger adults, they also exhibit specific articulatory difficulties. Although many physiological changes in orofacial functions occur in aging, only muscular endurance of the lips is related to age-related differences in speech production. This information is important for the development of speech interventions targeting older adults with speech motor disorders.