NCT05386394 · Johns Hopkins University
Transcranial Direct Current Stimulation in the Treatment of Primary Progressive Aphasia
What this study is about
While many have strongly suggested that transcranial direct current stimulation (tDCS) may represent a beneficial intervention for patients with primary progressive aphasia (PPA), this promising technology has not yet been applied widely in clinical settings.
View original scientific description
While many have strongly suggested that transcranial direct current stimulation (tDCS) may represent a beneficial intervention for patients with primary progressive aphasia (PPA), this promising technology has not yet been applied widely in clinical settings. This treatment gap is underscored by the absence of any neurally-focused standard-of-care treatments to mitigate the devastating impact of aphasia on patients' family, work, and social lives.
Interventions
DEVICE
Active tDCS + Language Therapy
Active tDCS stimulation will be delivered by a battery-driven constant current stimulator. The electrical current will be administered to a pre-specified region of the brain (inferior frontal gyrus). The stimulation will be delivered at an intensity of 2mA (estimated current density 0.04 milliamps (mA)/cm2; estimated total charge 0.048 Coulombs (C)/cm2) in a ramp-like fashion for a maximum of 20 minutes. Language therapy will be conducted in conjunction with stimulation and will target oral and written naming.
DEVICE
Sham tDCS + Language Therapy
During sham stimulation, current will be administered in a ramp-line fashion but after the ramping the intensity will drop to 0 mA. Language therapy targeting oral and written naming will be administered during sham tDCS stimulation.
Primary outcome measures
Immediate Change in Phonemic Accuracy
Time frame: Baseline and Immediate follow-up of 3-week intervention period
The primary outcome measure will be tDCS-induced change in performance on phonemic accuracy of trained items. Phonemic accuracy will be calculated on a scale of 0-100% with a higher number reflecting higher accuracy. The change in performance from baseline will be compared between the tDCS condition and the sham condition.
Immediate Change in Letter Accuracy
Time frame: Baseline and Immediate follow-up of 3-week intervention period
The primary outcome measure will be tDCS-induced change in performance on letter accuracy of trained items. Letter accuracy will be calculated on a scale of 0-100% with a higher number reflecting higher accuracy. The change in performance from baseline will be compared between the tDCS condition and the sham condition.
Change in Phonemic Accuracy at 3-month follow-up visit
Time frame: Baseline and 3 months post intervention
The primary outcome measure will be tDCS-induced change in performance on phonemic accuracy of trained items, 3 months following the discontinuation of intervention. Phonemic accuracy will be calculated on a scale of 0-100% with a higher number reflecting higher accuracy. The change in performance from baseline will be compared between the tDCS condition and the sham condition.
Change in Letter Accuracy at 3-month follow-up visit
Time frame: Baseline and 3 months post intervention
The primary outcome measure will be tDCS-induced change in performance on letter accuracy of trained items, 3 months following the discontinuation of intervention. Letter accuracy will be calculated on a scale of 0-100% with a higher number reflecting higher accuracy. The change in performance from baseline will be compared between the tDCS condition and the sham condition.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Presence of aphasia attributable to non-fluent PPA or logopenic PPA
- High school education (or more)
- Between the ages of 50 and 80
- Must be able to understand the nature of the study and give informed consent
Exclusion criteria
- Cognitive impairment of sufficient severity to preclude giving informed consent (Mini Mental State Examination \[MMSE\] less than 15)
- Any unrelated neurologic or physical condition that impairs communication ability
- History of unrelated neurological conditions, including but not limited to traumatic brain injury (TBI), stroke, or small vessel disease, that has resulted in a neurologic deficit
- 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
- A medically unstable cardiopulmonary or metabolic disorder
- Individuals with pacemakers or i
Where
- Baltimore, Maryland
- Philadelphia, Pennsylvania
Collaborators
National Institute on Aging (NIA)
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 5, 2026 · Source of record for eligibility and locations