Article

The purpose of this study was to define the acoustic voice and speech
characteristics of patients with Parkinson disease (PD). Seven female patients
with PD and seven female healthy controls participated in this study. Each
subject was instructed to vocalize extended corner vowels (/a/, /e/, /i/, /u/)
three times for at least 5 seconds at a comfortable voice loudness and tone. The
voice was analyzed using the Praat program. As a result, female patients with PD
showed a significant increase in jitter and noise-to-harmonics ratio (NHR). In
addition, F1 and F2 among the PD patients demonstrated asymmetric centralization
of unrounded vowels (/a/, /e/, /i/) in high/low/front/back positions of the
tongue, consequently leading to a significant decrease in vowel space area,
compared to healthy controls. This study showed the acoustic characteristics of
vowel sounds not only by laryngeal variables such as abnormal jitter and NHR, but
also by articulatory variables such as asymmetric centralization and reduced
vowel space area in female patients with PD. Therefore, it is important to use
these objective and sensitive variables to evaluate the status or severity of
hypokinetic dysarthria in patients with PD.

Langue : ANGLAIS