Acoustic and Perceptual Correlates of Vowel Articulation in Parkinson’s Disease With and Without Mild Cognitive Impairment: A Pilot Study

This pilot study investigates the added acoustic and perceptual effect of cognitive impairment on vowel articulation precision in individuals with Parkinson’s Disease (PD). We compared PD patients with and without Mild Cognitive Impairments (MCI) to elderly healthy controls on various acoustic measurements of the first and second formants of the vowels /i, u, a:, Open image in new window , a/, extracted from spontaneous speech recordings. In addition, 15 naive listeners performed intelligibility ratings on segments of the spontaneous speech. Results show a centralization of vowel formant frequencies, an increased formant frequency variability and reduced intelligibility in individuals with PD compared to controls. Acoustic and perceptual effects of cognitive impairments on vowel articulation precision were only found for the male speakers.