Speech and Voice Outcomes Following HD-tDCS Over the Left SMA

Louisiana State University and A&M College

Status: Not yet enrolling

Conditions: Parkinson Disease

Treatments: Device: Sham transcranial direct current stimulation; Device: Active transcranial direct current stimulation

Study type: Interventional

Funder types: Other

Identifiers

NCT06245070

IRBAM-21-1019

Details and patient eligibility

About

Pharmaceutical and neurosurgical treatments reliably ameliorate the cardinal motor symptoms in PD but, they often yield inconsistent outcomes for speech and voice disorders, with some studies showing exacerbation of pre-treatment deficits. Therefore, it is crucial to develop and optimize novel approaches that could simultaneously improve speech and voice deficits in PD and facilitate existing behavioral interventions. This project will investigate the immediate and short-term effects of multiple sessions of HD-tDCS over the left SMA on speech and voice deficits in PD.

Full description

Parkinson's disease (PD) is a movement disorder that affects more than one million individuals in the United States. Over 90 percent of individuals with PD manifest speech and voice impairments in the course of their disease, which can significantly compromise patients' quality of life. While pharmaceutical intervention and deep brain stimulation reliably improve the cardinal motor symptoms of PD, such as tremor, rigidity, and bradykinesia, the effects of these treatments on speech and voice are inconsistent, with some studies showing the exacerbation of pre-treatment deficits. This inconsistency often occurs because treatments are calibrated to ameliorate limb motor symptoms, with no direct optimization to improve speech and voice functions. However, there is no established non-invasive neurostimulation protocol for communication disorders in PD. Increasing evidence supports the application of non-invasive brain stimulation techniques such as transcranial direct current stimulation (tDCS) to improve both motor and non-motor symptoms in PD. However, limited evidence exists regarding the application of tDCS to improve speech and voice disorders in PD. Moreover, there is no established long-term effect of tDCS on speech and voice deficits in PD. In this proposed study, we will address these gaps by investigating the immediate and short-term effects of high definition-transcranial direct current stimulation (HD-tDCS) over the left supplementary motor area (SMA) on speech and voice deficits in 24 PD and 24 matched control participants.

Enrollment: 48 estimated patients

Sex: All

Ages: 18 to 80 years old

Volunteers: Accepts Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria:

• Clinical diagnosis of Parkinson's disease
• Native English speakers
• Adequate age-relative hearing and vision to perform the outlined tasks
• Able to provide their own written consent

Exclusion Criteria :

• Neurological disorders besides Parkinson's disease
• Previous brain surgery including deep brain stimulation
• Clinical diagnosis of dementia

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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48 participants in 2 patient groups

Active high definition transcranial direct current stimulation (HD-tDCS)

Experimental group

Description:

High-definition anodal transcranial direct current stimulation (2 milliamps \[mA\]) for 5 consecutive days (one session per day for 20 minutes each). The electrical current will be administered over the left Supplementary motor area. The stimulation will be delivered at an intensity of 2 milliamps (mA) for a maximum of 20 minutes.

Treatment:

Device: Active transcranial direct current stimulation

Sham high definition transcranial direct current stimulation (HD-tDCS)

Experimental group

Description:

High-definition sham transcranial direct current stimulation (2 milliamps \[mA\]) for 5 consecutive days (one session per day for 20 minutes each). The electrical current will be administered over the left Supplementary motor area. The current will be ramped up for the first 30 seconds following which the intensity will drop to 0 milliamps (mA).

Treatment:

Device: Sham transcranial direct current stimulation