Aging deficits in naturalistic speech production and monitoring revealed through reading aloud

The current study investigated how aging affects production and self-correction of errors in connected speech elicited via a read aloud task. Thirty-five cognitively healthy older and 56 younger participants read aloud 6 paragraphs in each of three conditions increasing in difficulty: (a) normal, (b) nouns-swapped (in which nouns were shuffled across pairs of sentences in each paragraph), and (c) exchange (in which adjacent words in every two sentences were reversed in order). Reading times and errors increased with task difficulty, but self-correction rates were lowest in the nouns-swapped condition. Older participants read aloud more slowly, and after controlling for aging-related advantages in vocabulary knowledge, produced more speech errors (especially in the normal condition), and self-corrected errors less often than younger participants. Exploratory analysis of error types revealed that aging increased the rate of function word substitution errors (saying the instead of a), whereas younger participants omitted content words more often than did older participants. This pattern of aging deficits reveals powerful effects of vocabulary knowledge on speech production and suggests aging speakers can compensate for aging-related decline in control over speech production with their higher vocabulary knowledge and careful attention to speech planning in more difficult speaking conditions. These results suggest a model of speech production in which planning of speech is relatively automatic, whereas monitoring and self-correction are more attention-demanding, in turn leaving speech production relatively intact in aging. (PsycINFO Database Record (c) 2019 APA, all rights reserved).