Unveiling the dynamics of discourse production in healthy aging and its connection to cognitive skills

Aging affects language asymmetrically, with a greater impact on language production than on comprehension. In this study, 256 Italian-speaking healthy adults were divided into four age groups: 64 young adults (20–39 years old), 64 middle-aged adults (40–59 years old), 64 mature adults (60–74 years old), and 64 older adults (75–89 years old). Their narrative discourse was assessed using a multilevel discourse analysis procedure. This captured age-related linear and nonlinear trends. Productivity showed a mixed pattern, with no age-related effects on word production and a linear decrease in speech rate. All microlinguistic (lexical and grammatical) and macrolinguistic (pragmatic and discourse level) abilities were affected by aging. Linear trends were observed for phonological, cohesion, and local coherence errors and for complete sentences. Nonlinear declines were observed for semantic and global coherence errors and for the production of informative words with significant modifications in performance after age 75. Working memory, attention, inhibitory control, and Theory of Mind also declined and were strongly associated with macrolinguistic abilities.