Age-related differences in the production of textual descriptions.

Narratives produced by 69 healthy Italian adults were analyzed for age-related changes of microlinguistic, macrolinguistic and informative aspects. The participants were divided into five age groups (20-24, 25-39, 40-59, 60-74, 75-84). One single-picture stimulus and two cartoon sequences were used to elicit three stories per subject. Age-related differences were found with respect to semantic paraphasias, paragrammatisms, syntactic complexity, degree of both local and global coherence, local coherence errors (like ambiguous referencing), and in the level of informativeness conveyed by the stories. The results showed some null effects of age, some effects with a sharp drop in performance in the oldest group, and several effects suggesting a gradual decrease in performance across age groups. No age differences were found with respect to phonological selection and noun-verb ratio. In the proportion of details vs. main themes, the results indicated a possibly better story construction ability in the middle aged (40-59) and young elderly (60-74) groups compared to the younger or the oldest group. Story-type (single picture vs. picture sequence) had a significant influence on some macrolinguistic and informativeness measures.