The relationship between verbal fragmentation and grammatical complexity in healthy individuals over 40

The development of language skills during adulthood and the changes in linguistic production processes have traditionally been considered a fixed phenomenon within conventional language acquisition approaches. However, a more detailed examination of the relationship between verbal fragmentation and grammatical complexity in linguistic production processes is necessary. This study aims to explore the interaction between these two linguistic components by analyzing narrative samples collected from healthy individuals over the age of 40. In this study, language samples were collected from participants using narrative tools "Frog, Where Are You?" story, the "Cookie Theft Picture," and the "Accident Composition Picture." The collected data were analyzed using the SALT-TK 18 Research software. Verbal fragmentation (VF) criteria included within-utterance pauses, omissions at the word and morpheme levels, errors, and repetitions. Grammatical complexity (GC), on the other hand, was evaluated using parameters such as mean length of utterance in morphemes (MLU-M), the proportion of complex sentences, and the number of verbals. The relationships between variables were examined through regression and correlation analyses. The regression analyses, where GK was considered the independent variable and VF the dependent variable, revealed that VF types such as morphological omissions (R²=0.59), single-word fillers (R²=0.53), lexical omissions (R²=0.55), and phrase-level revisions (R²=0.65) were influenced by GK. Notably, a strong positive correlation between MLU-M and clause density (p=0.854) reinforced the assumption that MLU-M could be regarded as a GK parameter in narrative samples of Turkish-speaking adults. These findings suggest that increased grammatical complexity affects VF types and may elevate the morphosyntactic processing load in Turkish discourse.