tACS for Aphasia After Stroke

Overseen By Sidney Schoenrock, MA

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Medical College of Wisconsin

Disqualifiers: Severe cognitive, psychiatric, cardiac, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 2

Duration: 2-3 weeks

50 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This study is evaluating whether a type of electrical stimulation may help improve language recovery for individuals who have had a stroke.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It is best to discuss this with the trial coordinators or your doctor.

Is tACS safe for humans?

While specific safety data for tACS (transcranial alternating current stimulation) is not provided in the research articles, similar non-invasive brain stimulation methods like tDCS (transcranial direct current stimulation) and rTMS (repetitive transcranial magnetic stimulation) have shown an excellent safety profile in studies for aphasia after stroke. ^{1 2 3 4 5}

How does the tACS treatment for aphasia after stroke differ from other treatments?

The tACS (transcranial alternating current stimulation) treatment for aphasia after stroke is unique because it uses electrical currents at specific frequencies (10-Hz and 40-Hz) to potentially enhance brain function, unlike traditional speech and language therapy or tDCS (transcranial direct current stimulation), which uses constant electrical currents. This approach may offer a novel way to improve language abilities by targeting brain activity patterns differently. ^{6 7 8 9 10}

What data supports the effectiveness of the treatment tACS for aphasia after stroke?

Research shows that non-invasive brain stimulation methods like transcranial direct current stimulation (tDCS) can help improve language skills in people with aphasia after a stroke. These methods, when combined with speech therapy, have shown promise in enhancing recovery by promoting brain plasticity (the brain's ability to adapt and change). ^{5 11 12 13 14}

Who Is on the Research Team?

Priyanka Shah-Basak, PhD

Principal Investigator

Medical College of Wisconsin

Are You a Good Fit for This Trial?

This trial is for adults who have had a stroke and are experiencing language difficulties (aphasia), as well as healthy adults without neurological issues. Participants must be fluent in English, at least 18 years old, and right-handed if they've had a stroke. They can't join if they have severe sensory impairments, untreated psychiatric diseases, unstable medical conditions, metal implants in the skull, or history of seizures or dyslexia.

Inclusion Criteria

I am fluent in English.

Healthy Controls: Fluent in English

I have never had a neurological or psychiatric disorder.

Exclusion Criteria

I have a history of seizures.

You have conditions that make it unsafe for you to have an MRI or tACS.

You have serious problems with thinking, hearing, or seeing that would make it difficult to do tests related to thinking and language.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

1 visit (in-person)

Treatment

Participants undergo HD-tACS at 10 Hz or 40 Hz, or sham-tACS, combined with language tasks and EEG monitoring

2-3 weeks

Multiple visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

1 week

1 visit (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• tACS 10-Hz
• tACS 40-Hz
• tACS sham

Trial Overview The study is testing three types of transcranial alternating current stimulation (tACS): one with a frequency of 10-Hz, another with 40-Hz, and a sham (placebo) treatment to see how they affect language recovery after stroke and general language functions.

How Is the Trial Designed?

Group I: tACS 10 Hz low frequency Experimental Treatment 1 Intervention

All participants in a within-subject design will receive high-Definition-tACS, delivered via a battery operated alternating current stimulator (Soterix) using two 3x1 center-surround montages. Targets of stimulation will be localized based on the 10-10 International EEG system with center electrodes placed at a frontal and a temporoparietal site. The current is turned on and increased in a ramplike fashion over approximately 30 seconds. Participants will undergo tACS with frequencies ranging from 4-40Hz for 20-minutes with 2 milliampere (mA) peak-to-peak intensity. For sham stimulation, tACS is turned off after the first 30 seconds.

Who Is Running the Clinical Trial?

Medical College of Wisconsin

Lead Sponsor

Trials

645

Recruited

1,180,000+

Published Research Related to This Trial

In a study of 37 stroke patients, speech therapy combined with transcranial direct current stimulation (tDCS) significantly improved language function, with an average increase in aphasia quotient (AQ%) of 14.94% after treatment.

Patients with less severe, fluent types of aphasia who started treatment within 30 days of their stroke showed the best responses, and those with hemorrhagic strokes had a higher likelihood of improvement compared to those with infarctions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Factors Associated with Good Responses to Speech Therapy Combined with Transcranial Direct Current Stimulation in Post-stroke Aphasic Patients. Jung, IY., Lim, JY., Kang, EK., et al.[2021]

Low-frequency transcranial magnetic stimulation (LF-rTMS) is the most effective non-invasive brain stimulation method for reducing global severity of post-stroke aphasia, based on a meta-analysis of 69 randomized controlled trials involving 1670 patients.

For specific language tasks, dual-transcranial direct-current stimulation (dual-tDCS) is superior for improving naming and repetition, while both anodal-tDCS and dual-tDCS are more effective than LF-rTMS for enhancing spontaneous speech.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparative efficacy of non-invasive brain stimulation for post-stroke aphasia: A network meta-analysis and meta-regression of moderators. Ding, X., Zhang, S., Huang, W., et al.[2022]

Transcranial direct current stimulation (tDCS) combined with language training showed improved verb production in a 43-year-old male with fluent-anomic aphasia after a stroke, suggesting enhanced language recovery.

The study indicates that using tDCS over Broca's area during language therapy may effectively support brain plasticity and improve language skills in individuals with aphasia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Translational treatment of aphasia combining neuromodulation and behavioral intervention for lexical retrieval: implications from a single case study. Galletta, EE., Vogel-Eyny, A.[2020]

Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) combined with speech and language therapy (SLT) significantly improves language abilities in patients with poststroke aphasia, as shown in a meta-analysis of 18 studies involving 536 participants.

The treatment is safe, with no reported adverse events, and the most effective LF-rTMS protocol was found to be 20 minutes per session at 90% of the resting motor threshold, administered 5 days a week for 2 weeks.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Low-Frequency Repetitive Transcranial Magnetic Stimulation in Patients With Poststroke Aphasia: Systematic Review and Meta-Analysis of Its Effect Upon Communication. Yao, L., Zhao, H., Shen, C., et al.[2021]

A systematic review of 25 studies involving 471 participants found that Transcranial Direct Current Stimulation (tDCS) did not improve overall functional communication in stroke patients, indicating limited efficacy for this primary outcome.

However, anodal tDCS, especially when applied over the left inferior frontal gyrus, showed a significant improvement in noun naming performance, suggesting it may be a promising targeted treatment for specific language deficits after stroke.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Transcranial direct current stimulation (tDCS) for improving aphasia after stroke: a systematic review with network meta-analysis of randomized controlled trials. Elsner, B., Kugler, J., Mehrholz, J.[2020]

Transcranial direct current stimulation (tDCS) shows promise as an adjunct treatment for improving speech-language deficits in patients with chronic post-stroke aphasia and primary progressive aphasia, by enhancing cortical excitability in language areas.

Current research emphasizes the need for more studies to connect improvements in neuropsychological test performance with real-world functional communication outcomes, as most existing studies focus on impairment rather than practical communication skills.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Transcranial direct current stimulation in post stroke aphasia and primary progressive aphasia: Current knowledge and future clinical applications. Sebastian, R., Tsapkini, K., Tippett, DC.[2019]

Cathodal transcranial direct current stimulation (tDCS) applied to the right inferior frontal gyrus significantly improved picture naming speed in 24 healthy subjects, suggesting a potential enhancement in language function.

The improvement in naming speed was linked to increased anatomical connectivity between the right Broca's area and the supplementary motor area, indicating that the effects of tDCS may depend on the brain's structural and functional connections.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Connectivity between right inferior frontal gyrus and supplementary motor area predicts after-effects of right frontal cathodal tDCS on picture naming speed. Rosso, C., Valabregue, R., Arbizu, C., et al.[2016]

Transcranial direct-current stimulation (tDCS) significantly improved articulatory accuracy in patients with aphasia after stroke, indicating its potential effectiveness in enhancing speech production.

While tDCS showed qualitative improvements in naming and syllable repetition tasks, these results were not statistically significant, suggesting that further research is needed to fully understand its impact.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of Anodal tDCS on Articulatory Accuracy, Word Production, and Syllable Repetition in Subjects with Aphasia: A Crossover, Double-Blinded, Sham-Controlled Trial. Vila-Nova, C., Lucena, PH., Lucena, R., et al.[2021]

A systematic review of 21 trials involving 421 participants found no evidence that transcranial direct current stimulation (tDCS) improves functional communication in people with aphasia after stroke, indicating low effectiveness for this purpose.

However, there is moderate evidence that tDCS may enhance noun naming accuracy, suggesting it could have some benefits in specific language tasks, although it did not show similar effects for verb naming.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Transcranial direct current stimulation (tDCS) for improving aphasia in adults with aphasia after stroke. Elsner, B., Kugler, J., Pohl, M., et al.[2023]

Citations

1. England pubmed.ncbi.nlm.nih.gov

Non-invasive brain stimulation as add-on therapy for subacute post-stroke aphasia: a randomized trial (NORTHSTAR). [2022]

2. Switzerland pubmed.ncbi.nlm.nih.gov

Induction of neuroplasticity and recovery in post-stroke aphasia by non-invasive brain stimulation. [2022]

3. Korea (South) pubmed.ncbi.nlm.nih.gov

The Factors Associated with Good Responses to Speech Therapy Combined with Transcranial Direct Current Stimulation in Post-stroke Aphasic Patients. [2021]

4. United States pubmed.ncbi.nlm.nih.gov

Comparative efficacy of non-invasive brain stimulation for post-stroke aphasia: A network meta-analysis and meta-regression of moderators. [2022]

5. Switzerland pubmed.ncbi.nlm.nih.gov

Translational treatment of aphasia combining neuromodulation and behavioral intervention for lexical retrieval: implications from a single case study. [2020]

6. United States pubmed.ncbi.nlm.nih.gov

Low-Frequency Repetitive Transcranial Magnetic Stimulation in Patients With Poststroke Aphasia: Systematic Review and Meta-Analysis of Its Effect Upon Communication. [2021]

7. England pubmed.ncbi.nlm.nih.gov

Transcranial direct current stimulation (tDCS) for improving aphasia after stroke: a systematic review with network meta-analysis of randomized controlled trials. [2020]

8. United States pubmed.ncbi.nlm.nih.gov

Excitatory repetitive transcranial magnetic stimulation induces improvements in chronic post-stroke aphasia. [2022]

9. United States pubmed.ncbi.nlm.nih.gov

Non-invasive repeated therapeutic stimulation for aphasia recovery: a multilingual, multicenter aphasia trial. [2022]

10. Netherlands pubmed.ncbi.nlm.nih.gov

Transcranial direct current stimulation in post stroke aphasia and primary progressive aphasia: Current knowledge and future clinical applications. [2019]

11. United States pubmed.ncbi.nlm.nih.gov

Connectivity between right inferior frontal gyrus and supplementary motor area predicts after-effects of right frontal cathodal tDCS on picture naming speed. [2016]

12. Brazil pubmed.ncbi.nlm.nih.gov

Transcranial brain stimulation (TMS and tDCS) for post-stroke aphasia rehabilitation: Controversies. [2020]

13. New Zealand pubmed.ncbi.nlm.nih.gov

Effect of Anodal tDCS on Articulatory Accuracy, Word Production, and Syllable Repetition in Subjects with Aphasia: A Crossover, Double-Blinded, Sham-Controlled Trial. [2021]

14. England pubmed.ncbi.nlm.nih.gov

Transcranial direct current stimulation (tDCS) for improving aphasia in adults with aphasia after stroke. [2023]