Articulation Features of Parkinson's Disease Patients with Subthalamic Nucleus Deep Brain Stimulation.
Voice and speech disorders are one of the most important issues after subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson's disease (PD) patients. However, articulation features in this patient population remain unclear.



We studied the articulation features of PD patients with STN-DBS.



Participants were 56 PD patients treated with STN-DBS (STN-DBS group) and 41 patients treated only with medical therapy (medical-therapy-alone group). Articulation function was evaluated with acoustic and auditory-perceptual analyses. The vowel space area (VSA) was calculated using the formant frequency data of three vowels (/a/, /i/, and /u/) from sustained phonation task. The VSA reportedly reflects the distance of mouth/jaw and tongue movements during speech and phonation. Correlations between acoustic and auditory-perceptual measurements were also assessed.



The VSA did not significantly differ between the medical-therapy-alone group and the STN-DBS group in the off-stimulation condition. In the STN-DBS group, the VSA was larger in the on-stimulation condition than in the off-stimulation condition. However, individual analysis showed the VSA changes after stopping stimulation were heterogeneous. In total, 89.8% of the STN-DBS group showed a large VSA size in the on- than in the off-stimulation condition. In contrast, the VSA of the remaining patients in that group was smaller in the on- than the off-stimulation condition.



STN-DBS may resolve hypokinesia of the articulation structures, including the mouth/jaw and tongue, and improve maximal vowel articulation. However, in the on-stimulation condition, the VSA was not significantly correlated with speech intelligibility. This may be because STN-DBS potentially affects other speech processes such as voice and/or respiratory process.
Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.
Yasuhiro
Y
Tanaka
Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.
Takashi
T
Tsuboi
Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.
Hirohisa
H
Watanabe
Department of Neurosurgery, Nagoya University Graduate School of Medicine, Japan.
Yasukazu
Y
Kajita
Department of Neurosurgery, Nagoya University Graduate School of Medicine, Japan.
Daisuke
D
Nakatsubo
Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, Japan.
Yasushi
Y
Fujimoto
Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.
Reiko
R
Ohdake
Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.
Mizuki
M
Ito
Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.
Naoki
N
Atsuta
Department of Health Science, Aichi Gakuin University, Nisshin-city, Aichi, Japan.
Masahiko
M
Yamamoto
Department of Neurosurgery, Nagoya University Graduate School of Medicine, Japan.
Toshihiko
T
Wakabayashi
Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.
Masahisa
M
Katsuno
Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.|Research Division of Dementia and Neurodegenerative Disease, Nagoya University Graduate School of Medicine, Japan.
Gen
G
Sobue
D000368:Aged; D001184:Articulation Disorders / Q000209:etiology / Q000628:therapy*; D046690:Deep Brain Stimulation / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010300:Parkinson Disease / Q000150:complications / Q000628:therapy*; D013065:Speech Intelligibility; D020531:Subthalamic Nucleus
Parkinson’s disease; acoustic analysis; articulation; deep brain stimulation; dysarthria; formant analysis; speech; speech disorder; speech intelligibility