tACS Modulates Speech and Cognitive Impairments in People With PD by Targeting the Medial Frontal Cortex

NCT07240272 | Completed DMC

• 1 other identifier: Nos.82172528
• Study Type: interventional
• Target: 28
• Locations: 1 country
• Sites: 1

Brief Summary

This clinical trial aims to study whether transcranial alternating current stimulation (tACS) applied to the medial frontal cortex (MFC) can improve speech and cognitive function in people with Parkinson's disease (PD), and to evaluate the safety of tACS. The main goals are to answer the following questions:

1. 1.Can tACS stimulation of the MFC improve executive functions in people with PD (such as reasoning, planning, inhibition, and complex problem-solving)?
2. 2.Can it improve the integration of auditory information and speech motor control during communication?
3. 3.Receive one extra 20-minute session of either real or sham tACS each day for two weeks
4. 4.Attend clinic visits before stimulation, right after the 2-week period, and again at 1 month and 3 months for assessments and tests
5. 5.Have their executive function scores, speech performance, and related brain activity recorded

Conditions

Parkinson Disease

Keywords

Parkinson's disease; transcranial alternating current stimulation; medial frontal cortex; executive functions; speech disorder

Outcome Measures

Primary Outcomes (4)

• Verbal Fluency Test (VFT)

  The VFT assesses abilities such as thought initiation, rapid word retrieval, and cognitive flexibility. It has two parts: 1.Phonemic Fluency Test (PFT), people needed to name as many Chinese words as possible beginning with "fa" or "xiao" within 60 seconds. 2.Semantic Fluency Test (SFT), people needed to name as many items as possible from categories such as "fruits," "vegetables," "animals," and "occupations" within 60 seconds. The number of correct and non-repeated words produced within the time limit were recorded.

  Assessments were completed at baseline, after two weeks of stimulation, and at 1- and 3-month follow-ups.

• Digit Span Test (DST)

  The DST assesses working memory and selective attention. People repeat a series of numbers in the same order (forward) or reverse order (backward) as spoken by the examiner. The maximum correctly repeated sequence length was recorded.

  Assessments were completed at baseline, after two weeks of stimulation, and at 1- and 3-month follow-ups.

• Trail Making Test (TMT)

  The TMT assesses complex visual scanning, conceptual tracking, cognitive flexibility and divided attention. It has two parts: TMT-A: People draw a trail by connecting 25 Arabic numbers in ascending order. TMT-B: the trail alternates between connecting 12 Arabic numbers and 12 Chinese characters. The time taken to complete each task is recorded.

  Assessments were completed at baseline, after two weeks of stimulation, and at 1- and 3-month follow-ups.

• Speech motor integration ability as assessed by a well-established paradigm: frequency-altered feedback (FAF) task

  In the FAF task, participants needed to sit in a sound-attenuated room and produce the vowel /u/ according to instructions. The acoustic signal is recorded and randomly shifted in pitch by an external device. The pitch-shifted voice is then fed back to the participant. This unexpected pitch perturbation elicits either an opposite or a following acoustic compensation response. The amplitude and timing of this response are recorded and used to assess the participant's speech-motor integration ability.

  Assessments were completed at baseline, after two weeks of stimulation, and at 1- and 3-month follow-ups.

Other Outcomes (2)

• The event-related potentials (ERPs) components recorded by Electroencephalography (EEG)

  Assessments were completed at baseline, after two weeks of stimulation, and at 1- and 3-month follow-ups.

• The hemodynamic responses in the executive process as assessed by Functional Near-Infrared Spectroscopy (fNIRS)

  Assessments were completed at baseline, after two weeks of stimulation, and at 1- and 3-month follow-ups.

Study Arms (2)

6Hz-group

EXPERIMENTAL

Other: 6Hz-tACS

Sham-group

SHAM COMPARATOR

Other: Sham-tACS

Interventions

6Hz-tACS OTHER

tACS applied to the MFC at a frequency of 6 Hz, using a high-definition 1×4 electrode configuration with individualized current intensity, delivered for 20 minutes.

6Hz-group

Sham-tACS OTHER

Except for turning down the current intensity to zero during the 20-minute period, all other parameters are identical to those in 6Hz-group.

Sham-group

Eligibility Criteria

• Age: 35 Years - 80 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Clinical diagnosis of Parkinson's disease.
• Aged 35-80 years.
• Absence of non-PD neurological disorders.
• No hearing impairment, dementia, psychiatric abnormalities, or history of neurosurgical treatment.

You may not qualify if:

• Pregnancy.
• Any contraindications to electrical stimulation.

Sponsors & Collaborators

• Ke Dong, MD: lead

Study Sites (1)

Department of Rehabilitation Medicine, The First Affiliated Hospital, Sun Yat-sen University

Guangzhou, Guangdong, 510000, China

Location

MeSH Terms

Conditions

Parkinson Disease; Speech Disorders

Condition Hierarchy (Ancestors)

Parkinsonian Disorders; Basal Ganglia Diseases; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Movement Disorders; Synucleinopathies; Neurodegenerative Diseases; Language Disorders; Communication Disorders; Neurobehavioral Manifestations; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Research Associate

Study Record Dates

• First Submitted: September 26, 2025
• First Posted: November 20, 2025
• Study Start: August 1, 2023
• Primary Completion: May 1, 2025
• Study Completion: August 1, 2025
• Last Updated: November 20, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR, ANALYTIC CODE

Locations

CN (1)