Continuous theta burst stimulation over right cerebellum for speech impairment in Parkinson's disease: study protocol for a randomized, sham-controlled, clinical trial

Xiaoxia Zhu; Guangyan Dai; Meng Wang; Mingdan Tan; Yongxue Li; Zhiqin Xu; Di Lei; Ling Chen; Xi Chen; Hanjun Liu

doi:10.3389/fnagi.2023.1215330

Continuous theta burst stimulation over right cerebellum for speech impairment in Parkinson's disease: study protocol for a randomized, sham-controlled, clinical trial

Front Aging Neurosci. 2023 Aug 15:15:1215330. doi: 10.3389/fnagi.2023.1215330. eCollection 2023.

Authors

Xiaoxia Zhu^#¹, Guangyan Dai^#¹, Meng Wang^#², Mingdan Tan¹, Yongxue Li¹, Zhiqin Xu¹, Di Lei¹, Ling Chen³, Xi Chen¹, Hanjun Liu^{1

4}

Affiliations

¹ Department of Rehabilitation Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
² Department of Radiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
³ Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
⁴ Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.

^# Contributed equally.

Abstract

Background: Speech impairment is a common symptom of Parkinson's disease (PD) that worsens with disease progression and affects communication and quality of life. Current pharmacological and surgical treatments for PD have inconsistent effects on speech impairment. The cerebellum is an essential part of sensorimotor network that regulates speech production and becomes dysfunctional in PD. Continuous theta-burst stimulation (cTBS) is a non-invasive brain stimulation technique that can modulate the cerebellum and its connections with other brain regions.

Objective: To investigate whether cTBS over the right cerebellum coupled with speech-language therapy (SLT) can improve speech impairment in PD.

Methods: In this randomized controlled trial (RCT), 40 patients with PD will be recruited and assigned to either an experimental group (EG) or a control group (CG). Both groups will receive 10 sessions of standard SLT. The EG will receive real cTBS over the right cerebellum, while the CG will receive sham stimulation. Blinded assessors will evaluate the treatment outcome at three time points: pre-intervention, post-intervention, and at a 12-week follow-up. The primary outcome measures are voice/speech quality and neurobehavioral parameters of auditory-vocal integration. The secondary outcome measures are cognitive function, quality of life, and functional connectivity determined by resting-state functional magnetic resonance imaging (fMRI).

Significance: This trial will provide evidence for the efficacy and safety of cerebellar cTBS for the treatment of speech impairment in PD and shed light on the neural mechanism of this intervention. It will also have implications for other speech impairment attributed to cerebellar dysfunctions.

Clinical trial registration: www.chictr.org.cn, identifier ChiCTR2100050543.

Keywords: Parkinson’s disease; auditory-vocal integration; cerebellum; continuous theta burst stimulation; hypokinetic dysarthria.

Grants and funding

This study was funded by grants from the National Natural Science Foundation of China (Nos. 82172528 and 81972147), the Guangdong Basic and Applied Basic Research Foundation (No. 2022A1515011203), the program of Guangdong Provincial Clinical Research Center for Rehabilitation Medicine (No. 2023B110003), the Guangdong Province Science and Technology Planning Project (No. 2017A050501014), and the Guangzhou Science and Technology Programme (No. 201604020115).