tDCS + Speech Therapy for Aphasia

Recruiting at 1 trial location

Overseen By E. Susan Duncan, PhD, CCC-SLP

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Louisiana State University and A&M College

Disqualifiers: Seizure history, Pregnancy, Pacemaker, others

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

Compensation: Varies

Number of Visits: 21

Duration: 8 weeks

30 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores whether combining speech therapy with transcranial direct current stimulation (tDCS) can aid individuals with chronic aphasia, a language disorder often caused by a stroke. Participants will receive either real or sham tDCS alongside their therapy to determine if the real stimulation enhances language recovery. Individuals who experienced a left hemisphere stroke over six months ago and have been diagnosed with aphasia may qualify, provided they have not recently undergone other speech therapy and can attend 16 sessions over 8 weeks. As an unphased trial, this study offers a unique opportunity to contribute to innovative research that could improve language recovery options for future patients.

Do I have to stop taking my current medications for the trial?

The trial protocol does not specify whether you need to stop taking your current medications. However, if you have a history of seizures or have changed seizure medication in the past 12 months, you may be excluded from participating.

What prior data suggests that transcranial direct current stimulation (tDCS) is safe for use in aphasia therapy?

Research has shown that transcranial direct current stimulation (tDCS) is generally safe and well-tolerated in human trials. Studies indicate that standard tDCS methods (up to 40 minutes, 4 milliamps) have not caused any serious side effects. This treatment is noninvasive and not painful, making it a promising option for helping people with aphasia recover language skills after a stroke.

Speech-language therapy (SLT) is a common and safe method for improving speech and language skills in people with aphasia. When combined with tDCS, this therapy might offer even greater benefits without major safety concerns.

Overall, research supports the safety of both tDCS and SLT, providing a strong basis for their use in clinical settings. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about using transcranial direct current stimulation (tDCS) combined with speech therapy for aphasia because it offers a novel approach compared to traditional speech-language therapy alone. Unlike standard treatments that primarily focus on rehabilitating language skills through practice and exercises, tDCS involves applying a mild electrical current to specific brain areas, potentially enhancing the brain's ability to repair and reorganize itself. This technique could speed up recovery and improve outcomes by stimulating brain regions involved in speech and language. Additionally, the use of a sham comparator allows researchers to assess the true efficacy of tDCS, helping to distinguish its benefits from the placebo effect.

What evidence suggests that this trial's treatments could be effective for aphasia?

This trial will compare the effects of anodal transcranial direct current stimulation (A-tDCS) combined with speech-language therapy (SLT) to a sham version of tDCS combined with SLT. Studies have shown that using a gentle electrical treatment like A-tDCS with SLT can aid people with language problems after a stroke. Research suggests this combination might enhance their ability to speak and repeat words. Some studies indicate that the electrical treatment in tDCS can enhance traditional language therapy. However, other studies have mixed results, with some showing no significant difference when comparing A-tDCS to a sham version. Overall, while the results are promising, they vary, so more research is needed to confirm its effectiveness. ^{1 3 5 6 7}

Who Is on the Research Team?

E. Susan Duncan, PhD, CCC-SLP

Principal Investigator

City University of New York

Are You a Good Fit for This Trial?

This trial is for right-handed, English-speaking adults with a high school education who had a single-event left hemisphere stroke over 6 months ago and have chronic aphasia. They must not be receiving other speech therapies during the study or have any conditions that would interfere with MRI scans, such as metal implants or pregnancy.

Inclusion Criteria

I can do the tasks needed for therapy, even with my speech difficulties.

High school education or equivalent

I can do the speaking and MRI tasks needed for the study.

Exclusion Criteria

I haven't had seizures or changed seizure medication in the last year.

You have a hairstyle that prevents electrodes from touching your scalp.

Failed vision or hearing screening

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person), 1 visit (virtual)

Pre-Treatment Assessment

Participants complete behavioral assessments and brain scans before therapy

4 weeks

2 visits (in-person)

Treatment

Participants receive tDCS and aphasia therapy for 8 weeks

8 weeks

16 visits (in-person)

Post-Treatment Assessment

Behavioral assessments and brain scans are conducted immediately after therapy

1 week

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

8 weeks

1 visit (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• Anodal transcranial direct current stimulation
• Sham transcranial direct current stimulation
• Speech-Language Therapy (SLT)

Trial Overview The study tests if brain stimulation using transcranial direct current stimulation (tDCS) can improve language abilities in people with post-stroke aphasia when combined with verb network strengthening treatment (VNeST). Participants receive weak electrical currents to their scalp twice weekly for 8 weeks during speech therapy sessions.

How Is the Trial Designed?

Group I: A-tDCS & speech-language therapy Experimental Treatment 2 Interventions

Anodal transcranial direct current stimulation (2 milliamps \[mA\]) plus aphasia therapy for 16 sessions (20-minutes per each 60-minute treatment session) over the course of 8 weeks. The electrical current will be administered over ventral inferior frontal gyrus. The stimulation will be delivered at an intensity of 2 milliamps (mA) for a maximum of 20 minutes.

Group II: Sham-tDCS & speech-language therapy Placebo Group 2 Interventions

Sham transcranial direct current stimulation (2 milliamps \[mA\]) plus aphasia therapy for 16 sessions (20-minutes per each 60-minute treatment session) over the course of 8 weeks. Electrodes will be placed as in A-tDCS. Current will be ramped up for the first 30 seconds following which the intensity will drop to 0 milliamps (mA).

Who Is Running the Clinical Trial?

Louisiana State University and A&M College

Lead Sponsor

Trials

12

Recruited

1,100+

City University of New York

Lead Sponsor

Trials

23

Recruited

6,000+

Published Research Related to This Trial

In a study involving 10 individuals undergoing standard aphasia therapy, 70% expressed interest in and were eligible for transcranial direct current stimulation (tDCS), which was administered during therapy sessions.

Data from four participants showed a large effect size (Cohen's d = 1.32) favoring active tDCS over sham stimulation, suggesting that tDCS may enhance communication outcomes in aphasia therapy, although one participant with severe deficits did not benefit.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical Feasibility of Combining Transcranial Direct Current Stimulation with Standard Aphasia Therapy. Duncan, ES., Nakkawita, SG.[2022]

A systematic review of 12 trials involving 136 participants found no evidence that transcranial direct current stimulation (tDCS) improves functional communication or language impairment in stroke patients with aphasia.

The meta-analysis of six trials indicated that tDCS did not significantly enhance outcomes in picture naming tasks, suggesting that it may not be an effective adjunct to speech and language therapy for aphasia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Transcranial direct current stimulation (tDCS) for improving aphasia in patients with aphasia after stroke. Elsner, B., Kugler, J., Pohl, M., et al.[2022]

A systematic review of five trials with 54 participants found no evidence that transcranial direct current stimulation (tDCS) improves speech and language therapy outcomes for stroke patients with aphasia.

While no adverse events were reported, the studies primarily measured picture naming rather than real-life communication, and cathodal tDCS over the non-lesioned hemisphere showed potential as a promising approach.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Transcranial direct current stimulation (tDCS) for improving aphasia in patients after stroke. Elsner, B., Kugler, J., Pohl, M., et al.[2022]

Transcranial direct current stimulation (tDCS) shows promise as an adjuvant treatment for improving speech production in chronic stroke patients with aphasia, based on preliminary evidence.

Further research is needed to fully understand how tDCS works, its optimal application in language rehabilitation, and how it interacts with existing therapies to enhance long-term recovery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Can tDCS enhance treatment of aphasia after stroke? Holland, R., Crinion, J.[2022]

Transcranial direct current stimulation (tDCS) combined with speech and language treatment (SLT) is safe for stroke survivors with aphasia, showing no serious adverse events during a six-week treatment involving 30 sessions.

Participants receiving active tDCS exhibited greater improvements in functional language compared to those receiving sham treatment, suggesting that tDCS may enhance the effectiveness of SLT, although the superiority of one stimulation polarity over another remains unclear.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Extended fMRI-Guided Anodal and Cathodal Transcranial Direct Current Stimulation Targeting Perilesional Areas in Post-Stroke Aphasia: A Pilot Randomized Clinical Trial. Cherney, LR., Babbitt, EM., Wang, X., et al.[2021]

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]

In a study involving 37 participants with moderate to severe aphasia, repeated anodal transcranial direct current stimulation (A-tDCS) did not show a significant positive impact on language recovery when combined with language therapy, compared to a sham stimulation group.

Both groups showed improvement in language abilities after therapy, but there were no statistically significant differences in outcomes between the A-tDCS and control groups, indicating that A-tDCS may not provide functional benefits in early post-stroke rehabilitation for aphasia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

No effects of anodal transcranial direct stimulation on language abilities in early rehabilitation of post-stroke aphasic patients. Polanowska, KE., Leśniak, M., Seniów, JB., et al.[2019]

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]

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]

In a study involving 24 patients with non-fluent aphasia, both anodal transcranial direct current stimulation (A-tDCS) and sham stimulation (S-tDCS) combined with speech and language therapy (SLT) led to significant improvements in naming ability, indicating that therapy itself is beneficial.

While the A-tDCS group showed higher effect sizes in naming time post-treatment and at the 3-month follow-up, the overall evidence for A-tDCS providing additional language gains was weak, suggesting that more research is needed to confirm its effectiveness in early post-stroke rehabilitation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Anodal transcranial direct current stimulation in early rehabilitation of patients with post-stroke non-fluent aphasia: a randomized, double-blind, sham-controlled pilot study. Polanowska, KE., Leśniak, MM., Seniów, JB., et al.[2016]

Transcranial direct current stimulation (tDCS) applied to the left inferior frontal gyrus significantly improved language abilities in patients with nonfluent poststroke aphasia when combined with speech language therapy, as shown by a higher Aphasia Quotient in the A-tDCS group compared to the sham group (72.99 vs. 46.18).

The study involved 18 patients over four weeks, with results indicating that tDCS enhances the effectiveness of speech language therapy, particularly in areas other than comprehension, suggesting a beneficial mechanism of action for language recovery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of Anodic Transcranial Direct Current Stimulation Combined With Speech Language Therapy on Nonfluent Poststroke Aphasia. Zhao, Q., Wang, J., Li, Z., et al.[2022]

In a study involving 11 chronic stroke patients with aphasia, dual transcranial direct current stimulation (tDCS) showed a significant improvement in naming response times compared to baseline, suggesting enhanced efficacy over single tDCS.

Both single and dual tDCS improved the number of correct responses in naming tasks, but dual tDCS, which targeted both the left and right inferior frontal gyri, may offer greater benefits for language recovery in stroke patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of dual transcranial direct current stimulation for aphasia in chronic stroke patients. Lee, SY., Cheon, HJ., Yoon, KJ., et al.[2021]

Citations

1. sciencedirect.com sciencedirect.com/science/article/pii/S2666459325000885

Effect of transcranial direct current stimulation combined ... tDCS combined with SLT demonstrates potential enhancement in language recovery on post-ischemic stroke aphasia. The combination may augment speech content, ...

2. pubs.asha.org pubs.asha.org/doi/10.1044/2024_AJSLP-23-00312

Effectiveness of Transcranial Direct Current Stimulation as ... All SRs and one MA reported improvements following tDCS stimulation for general aphasia abilities and measures of repetition and speech fluency.

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6528187/

Transcranial direct current stimulation (tDCS) for improving ... Currently there is no evidence of the effectiveness of tDCS (anodal tDCS, cathodal tDCS and Dual‐tDCS) versus control (sham tDCS) for improving functional ...

4. ahajournals.org ahajournals.org/doi/10.1161/STROKEAHA.122.041557

Transcranial Direct-Current Stimulation in Subacute Aphasia This single-center, randomized, double-blind, sham-controlled efficacy trial tested the hypothesis that anodal tDCS augments language therapy in subacute ...

5. clinicaltrials.gov clinicaltrials.gov/study/NCT01486654?cond=Agrammatism&viewType=Table&rank=9

Transcranial Direct Current Stimulation and Aphasia ... The purpose of this study is to evaluate the effectiveness of small amounts of electrical current, applied without surgery to the brain, in combination with ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC5007190/

Safety of transcranial Direct Current Stimulation: Evidence ... To date, the use of conventional tDCS protocols in human trials (≤40 min, ≤4 mA, ≤7.2 Coulombs) has not produced any reports of a Serious Adverse Effect or ...

7. clinicaltrials.gov clinicaltrials.gov/study/NCT01486654?term=AREA%5BBasicSearch%5D(aphasia)%20AND%20AREA%5BSponsorSearch%5D(NIDCD)&rank=6

Transcranial Direct Current Stimulation and Aphasia ... This study proposes to evaluate the safety, feasibility, and effectiveness of anodal and cathodal tDCS in study subjects with Broca's aphasia after stroke, ...