Changes in speech prosody perception during Parkinson's disease: A comprehensive analysis

Introduction: Parkinson's disease (PD) is a progressive neurodegenerative disorder that affects approximately 1%-2% of individuals aged 60 and above. Communication disorders in PD can significantly impact the overall quality of life. As prosody plays a vital role in verbal communication, the present study examines Persian prosody perception in PD, focusing on linguistic and emotional aspects of prosody. Methods: This cross-sectional study aimed to compare the perception of linguistic and emotional prosody in three groups: middle-aged adults ( n = 22; mean age = 50.40 years), healthy older adults ( n = 22; mean age = 68.31 years), and individuals with Parkinson's disease ( n = 22; mean age = 65years). All individuals with PD were classified in stages 1; 1.5; 2; 2.5, and 3 of the disease using the Hoehn and Yahr scale. All participants had an MMSE score of 24 or above. The Florida Affect Battery (FAB) was used to evaluate prosody perception. This Battery was validated in the Persian language and its reliability and validity were reported as 94 % and 100 % respectively. Results: Participants with PD presented significantly lower scores than the older adults in all subtests of the FAB ( p < 0.05), while healthy older adults were significantly different only in linguistic discrimination (beta = -2.14; -3.68 to -0.61), and linguistic naming of prosody (beta = 1.25; 0.17 to 2.33) compared to middle-aged adults. Conclusions: The present study sheds light on the influence of PD on Persian prosody perception. Given the crucial role of prosody in verbal communication, these findings enhance our understanding of communication disorders in PD and could bring attention to consider prosody perception, among other aspects, when assessing individuals affected by PD.