Pauses as a Quantitative Measure of Linguistic Planning Challenges in Parkinson's Disease

Background/Objectives: Pausing is a multifaceted phenomenon relevant to motor and cognitive disorders, particularly Parkinson's Disease (PD). Thus, examining pauses as a metric for linguistic planning and motor speech difficulties in PD patients has gained significant attention. Here, we examined the production of silent and filled pauses (indexing difficulties at various linguistic processing levels) during narrative tasks to investigate the interplay between pausing behavior and informativeness/productivity measures. Methods: Individuals' pausing patterns during narratives were analyzed relative to their syntactic context (within and between sentences expressing motor and non-motor related content), in 29 patients in the mild-to-moderate stage of PD, and 29 age-matched healthy speakers. The interaction between communicative metrics (informativeness and productivity), motor symptoms, cognitive capabilities, and pausing behavior was explored to characterize the mechanisms underlying pause production and its influence on discourse content. Results: PD patients' pausing profile was characterized by an overall reduced number of pauses, longer silent pauses and fewer/shorter filled pauses, particularly before words that extend or specify the semantic content of sentences. Contrary to what was observed in healthy speakers, both the duration of silent pauses and the total number and duration of filled pauses could explain a significant proportion of variance in informativeness measures. Silent pause duration significantly correlated with measures of lexical access, indicating that cognitive processes influence pause production, while motor speech and cognitive challenges may also interact. Conclusions: Current results have significant implications for understanding discourse difficulties linked to PD and for formulating intervention strategies to improve communication efficacy.