Prosodic Differences in Mandarin Speakers With Alzheimer’s Disease

Abstract

Alzheimer’s Disease (AD) is a progressive neurodegenerative disorder affecting approximately 50 million people worldwide. Given AD’s potential to develop decades prior to the onset of cognitive symptoms, early detection is critical for improved intervention. Previous research has shown that acoustic analysis can identify biomarkers from speech for earlier diagnosis [Martínez-Nicolás et al., 2021, Frontiers in Psychology, 12, 645]. Among the acoustic parameters studied, intonation has drawn a reliable distinction between healthy controls and AD patients for Spanish speakers, with patients demonstrating less variability in pitch [Meilán et al., 2012, The Spanish Journal of Psychology, 15(2), 487-494]. However, it remains unclear whether such changes can be observed in languages with lexical tone. The present study seeks to substantiate the utility of prosodic change as an acoustic biomarker for AD in Mandarin speech. Preliminary comparisons of prosodic trajectories (intrasyllabic, intersyllabic, phonation) from four AD patients (2 males, 2 females) were compared to speech from four gender-matched neurotypical controls. Preliminary results indicate reductions to prosodic trajectories for AD patients in Mandarin. Our findings are consistent with previous observations for Spanish that AD patients produce reduced prosodic variation, even in a language with lexical tone.