tACS to Enhance Language Abilities

NCT ID: NCT06092814

Last Updated: 2025-08-08

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 120 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-07-12
• Study Completion Date: 2028-08-31

Brief Summary

The goal of this study is to see if transcranial alternating current stimulation (tACS) can be used to enhance language abilities in people with post-stroke aphasia. Participants will receive real and sham tACS in conjunction with various language tests. Researchers will compare the post-stroke aphasia group with aged matched controls to see if brain response to tACS differs between groups.

Detailed Description

This research will investigate whether transcranial alternating current stimulation (tACS), a form of noninvasive brain stimulation, can be used to enhance language abilities in people with aphasia (PWA) due to stroke and healthy older adults when compared to placebo (sham) tACS. The investigators hypothesize that alpha vs. sham tACS will improve language abilities. In addition, the investigators propose that alpha vs. sham tACS will increase local alpha power as well as alpha-induced functional connectivity, and the degree to which alpha tACS increases will be related to the degree of language performance improvement. Finally, the investigators hypothesize that PWA will exhibit abnormalities in alpha-related activity when compared to matched controls, and aphasia severity will be associated with the degree of PWA dysfunction in alpha power and alpha-driven functional connectivity.

Conditions

Stroke; Aphasia, Acquired; Aphasia

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: TREATMENT
• Blinding Strategy: TRIPLE

Study Groups

real-tACS

The active stimulation will consist of an alternating current delivered in the alpha frequency band with a peak-to-peak intensity of 4 milliamps (mA) for 20 minutes. Participants will complete sentence completion and verb generation task during stimulation.

Group Type: ACTIVE_COMPARATOR

Active transcranial alternating current stimulation (tACS)

Intervention Type: DEVICE

Transcranial Alternating Current Stimulation (tACS) is a device that applies a low-intensity electrical current to the brain through electrodes on the scalp.

sham-tACS

Sham stimulation involves the delivery of 60 seconds of the actual stimulation waveform ("ramp up") which is then gradually reduced to 0 milliamps (mA) ("ramp down"). Participants will complete sentence completion and verb generation task during stimulation.

Group Type: PLACEBO_COMPARATOR

Active transcranial alternating current stimulation (tACS)

Intervention Type: DEVICE

Transcranial Alternating Current Stimulation (tACS) is a device that applies a low-intensity electrical current to the brain through electrodes on the scalp.

Interventions

Active transcranial alternating current stimulation (tACS)

Transcranial Alternating Current Stimulation (tACS) is a device that applies a low-intensity electrical current to the brain through electrodes on the scalp.

Intervention Type: DEVICE

Other Intervention Names

Sham transcranial alternating current stimulation [(ACS)

Eligibility Criteria

Inclusion Criteria

1. Presence of aphasia

2. Suffered a single, left hemisphere stroke

3. Stroke ≥6 months old (chronic) at the time of enrollment

1. Right-handedness

2. Must be able to understand the nature of the study, and give informed consent

Exclusion Criteria

1. Inability to understand the nature of the study

2. Marked naming impairment

3. Impaired non-verbal, conceptual processing

4. History of significant medical or neurological disorder (other than stroke)

5. History of significant or poorly controlled psychiatric disorders

6. Current abuse of alcohol or drugs, prescription or otherwise

7. Nursing a child, pregnancy, or intent to become pregnant during the study

8. Clinically significant hearing loss

9. Contraindications to tACS

10. Contraindications to MRI

1. Diagnosis of a neurodegenerative disease or clinically significant cognitive complaint

2. Any unrelated neurologic or physical condition that impairs communication ability

3. History of unrelated neurological conditions including but not limited to traumatic brain injury, stroke, or small vessel disease that has resulted in a neurologic deficit

4. Any additional neurological condition that would likely reduce the safety of study participation, including central nervous system (CNS) vasculitis, intracranial tumor, intracranial aneurysm, multiple sclerosis or arteriovenous malformations

5. A medically unstable cardiopulmonary or metabolic disorder

6. Terminal illness associated with survival <12 months

7. Major active psychiatric illness that may interfere with required study procedures or treatments as determined by the enrolling physician

8. Current abuse of alcohol or drugs, prescription or otherwise

9. Contraindications to tACS

10. Contraindications to MRI

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 85 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of Pennsylvania

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

University of Pennsylvania

Philadelphia, Pennsylvania, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Daniela Sacchetti, MS

Role: CONTACT

danielas@pennmedicine.upenn.edu

215 573 4336

Denise Harvey, PhD

Role: CONTACT

harveyde@pennmedicine.upenn.edu

215 573 4336

Facility Contacts

Denise Harvey, PhD

Role: primary

harveyde@pennmedicine.upenn.edu

215-573-4336

Daniela Sacchetti, MS

Role: backup

danielas@pennmedicine.upenn.edu

215 573 4336

Other Identifiers

854139

Identifier Type: -

Identifier Source: org_study_id