Brain Stimulation for Dyslexia

Overseen By Tess Fotidzis, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Vanderbilt University

Must not be taking: Psychotropics, Seizure meds, Stroke meds

Disqualifiers: Intellectual disability, Neurologic pathology, Psychiatric disorders, others

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

Compensation: Varies

Number of Visits: 3

100 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a new method to enhance reading skills in adults with dyslexia through non-invasive brain stimulation. Researchers aim to determine if this technique improves reading more effectively than traditional methods. The study compares various brain stimulation types, including CCN real non-invasive brain stimulation intervention, RLN and CCN real non-invasive brain stimulation intervention, and RLN real non-invasive brain stimulation intervention, alongside a sham version to assess real effects. Right-handed, native English-speaking adults who struggle with reading may qualify for this trial. As an unphased trial, it offers a unique chance to contribute to groundbreaking research that could transform dyslexia treatment.

Will I have to stop taking my current medications?

The trial excludes participants who are taking psychotropic medications or medications known to increase the risk of seizures or strokes. If you are on such medications, you may need to stop taking them to participate.

What prior data suggests that this non-invasive brain stimulation protocol is safe for adults with dyslexia?

Research has shown that non-invasive brain stimulation, such as transcranial direct current stimulation (tDCS), is generally safe. In studies involving 745 children and teens across 35 trials, no serious side effects occurred during 6,587 sessions, indicating that the treatment is usually well-tolerated.

For both the RLN and CCN brain stimulation methods, past research has found positive effects on brain functions related to reading and language skills. These benefits include fewer epileptic seizures and improvements in balance and math skills. Additionally, transcranial random noise stimulation (tRNS) has demonstrated stronger effects than tDCS on language and learning abilities.

Overall, while this specific trial is new, evidence from other studies suggests these brain stimulation methods are safe for people. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about these treatments for dyslexia because they use non-invasive brain stimulation, a method that directly targets specific brain areas involved in reading and language processing. Unlike traditional dyslexia interventions, which often focus on behavioral therapies and educational strategies, these treatments aim to enhance brain function through stimulation of the left dorsolateral prefrontal cortex and left angular gyrus. This approach has the potential to improve reading skills by directly modifying neural activity, offering a novel avenue for intervention. Additionally, the use of real versus sham stimulation allows for precise measurement of the treatment's effectiveness, potentially leading to faster and more targeted improvements in dyslexia management.

What evidence suggests that this trial's brain stimulation treatments could be effective for dyslexia?

Research has shown that non-invasive brain stimulation can help people with dyslexia improve their reading skills. In this trial, participants will receive different types of brain stimulation. The RLN and CCN brain stimulation methods, part of separate treatment arms in this trial, target brain areas involved in reading. Studies indicate that combining methods like transcranial direct current stimulation (tDCS) with reading exercises can enhance specific reading abilities, such as recognizing sounds in words. Additionally, tDCS has been linked to better reading speed and accuracy. Overall, these findings provide promising evidence that brain stimulation could be a useful tool for improving reading skills in individuals with dyslexia. ^{1 3 6 7 8}

Who Is on the Research Team?

Katherine S. Aboud, PhD

Principal Investigator

Vanderbilt University

Are You a Good Fit for This Trial?

This trial is for right-handed, native English-speaking adults aged 18-40 with dyslexia. Participants must not have a low IQ, developmental disorders, visual or hearing impairments that can't be corrected, metal devices in their body, recent migraines, severe fatigue or psychiatric issues. They should not be pregnant and mustn't take certain medications.

Inclusion Criteria

I am right-handed and only speak English.

Exclusion Criteria

I have a known neurological condition such as epilepsy or brain injury.

I have been recently diagnosed with migraines.

Hair styles that do not allow for proper EEG net fitting, or that pose potential risks for damage to EEG net

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Baseline Assessment

Establish baseline behavior and brain measures of the individual

1 day

1 visit (in-person, 3.5 hours)

Intervention

Behavioral and non-invasive stimulation intervention, including MRI and EEG sessions

1 day

1 visit (in-person, 3 hours)

Follow-up Assessment

Establish prolonged intervention effects using behavior and brain measures

1 day

1 visit (in-person, 2.5 hours)

Long-term Follow-up

Participants are monitored for changes in reading comprehension and brain activations

12 months

What Are the Treatments Tested in This Trial?

Interventions

• CCN real non-invasive brain stimulation intervention
• RLN and CCN real non-invasive brain stimulation intervention
• RLN real non-invasive brain stimulation intervention
• Sham intervention

Trial Overview The study tests the effect of non-invasive brain stimulation on reading comprehension in adults with dyslexia. It compares different types of stimulations (RLN and CCN) against a sham intervention to see which improves reading skills and brain function.

How Is the Trial Designed?

Group I: Reading and Language Network (RLN) Experimental Treatment 1 Intervention

Participants receiving real stimulation to the left angular gyrus.

Group II: RLN and CCN Experimental Treatment 1 Intervention

Participants receiving real stimulation to the left dorsolateral prefrontal cortex and left angular gyrus.

Group III: Sham stimulation Placebo Group 1 Intervention

Participants receiving sham stimulation.

Who Is Running the Clinical Trial?

Vanderbilt University

Lead Sponsor

Trials

714

Recruited

6,143,000+

National Institutes of Health (NIH)

Collaborator

Trials

2,896

Recruited

8,053,000+

Published Research Related to This Trial

A systematic review of 64 studies involving 2262 participants found that transcranial direct current stimulation (tDCS) has a low dropout rate (6% for active and 7.2% for sham), indicating good acceptability among participants.

Despite the low dropout rates, many studies inadequately reported adverse events (AEs), highlighting a need for improved guidelines to standardize AE reporting in tDCS research.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A Systematic Review on the Acceptability and Tolerability of Transcranial Direct Current Stimulation Treatment in Neuropsychiatry Trials. Aparício, LVM., Guarienti, F., Razza, LB., et al.[2018]

Eighteen children and adolescents with dyslexia underwent 18 sessions of transcranial direct current stimulation (tDCS) combined with cognitive training, resulting in significant improvements in reading low frequency words and non-words, with effects lasting one month after treatment.

The study found no adverse effects from the tDCS treatment, indicating it is a safe and feasible option for enhancing reading abilities in children and adolescents with dyslexia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Evidence for reading improvement following tDCS treatment in children and adolescents with Dyslexia. Costanzo, F., Varuzza, C., Rossi, S., et al.[2018]

Non-invasive electrical brain stimulation (NEBS), particularly through techniques like transcranial direct current stimulation (tDCS) and transcranial random noise stimulation (tRNS), can effectively modulate brain function and improve motor skills in healthy individuals and patients with motor disabilities.

The article outlines a detailed protocol for applying tDCS to the primary motor cortex, discussing the benefits and drawbacks of different electrode placements, while also addressing safety and tolerability concerns associated with these stimulation methods.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Non-Invasive Electrical Brain Stimulation Montages for Modulation of Human Motor Function. Curado, M., Fritsch, B., Reis, J.[2018]

A study involving 26 children and adolescents with dyslexia showed that multiple sessions of transcranial direct current stimulation (tDCS) combined with reading training led to significant and lasting improvements in reading abilities, particularly in non-word and low-frequency word reading efficiency, even 6 months after treatment.

The study found no long-term adverse effects from tDCS, suggesting it is a safe and effective rehabilitative approach for enhancing reading skills in individuals with dyslexia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Long-lasting improvement following tDCS treatment combined with a training for reading in children and adolescents with dyslexia. Costanzo, F., Rossi, S., Varuzza, C., et al.[2020]

Transcranial direct current stimulation (tDCS) targeting the left temporo-parietal cortex has shown significant improvements in reading abilities, particularly in individuals with developmental dyslexia (DD), based on a systematic review of nine studies.

tDCS was especially effective for poor readers and those with DD, enhancing skills like word decoding in adults and non-word reading in younger individuals, while not benefiting proficient readers, suggesting its potential as a targeted intervention for reading difficulties.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

tDCS Modulatory Effect on Reading Processes: A Review of Studies on Typical Readers and Individuals With Dyslexia. Cancer, A., Antonietti, A.[2020]

Noninvasive brain stimulation (NIBS) combined with reading training has shown promise in improving reading performance in both children and adults with dyslexia, based on a review of 15 studies.

Targeting classical reading areas with NIBS can enhance various reading-related skills, and there is potential for modulating auditory cortex function to prevent phonological difficulties associated with dyslexia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The use of noninvasive brain stimulation techniques to improve reading difficulties in dyslexia: A systematic review. Turker, S., Hartwigsen, G.[2023]

Low intensity transcranial electrical stimulation (TES) is considered safe, with no serious adverse events reported in over 18,000 sessions across various populations, including healthy individuals and patients with neurological or psychiatric conditions.

While moderate adverse events like skin burns from tDCS are rare, mild adverse events such as headaches and fatigue are more common, and the safety profile is consistent across different age groups and vulnerable populations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Low intensity transcranial electric stimulation: Safety, ethical, legal regulatory and application guidelines. Antal, A., Alekseichuk, I., Bikson, M., et al.[2023]

The study assessed the safety of 1.5-mA transcranial direct current stimulation (tDCS) on 49 fasting healthy individuals during Ramadan, finding no serious adverse events or discomfort during the sessions.

There was no significant difference in side effects between active tDCS and sham stimulation, indicating that the tDCS protocol used is safe for fasting adults.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety of Transcranial Direct Current Stimulation of Frontal, Parietal, and Cerebellar Regions in Fasting Healthy Adults. Almousa, A., Alajaji, R., Alaboudi, M., et al.[2020]

Transcranial Direct Current Stimulation (tDCS) is generally considered safe, but there are concerns that it could lead to significant negative effects in healthy individuals.

The scientific community needs to be alerted about the potential risks of tDCS, emphasizing the importance of protecting healthy volunteers from possible harm.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety of transcranial direct current stimulation in healthy participants. Boccard-Binet, S., Sen, A.[2021]

Transcranial direct current stimulation (tDCS) significantly reduced depression scores in HIV patients co-diagnosed with Major Depressive Disorder (MDD) after a 2-week treatment, indicating its potential as an effective intervention.

The treatment was found to be safe, with no serious adverse events reported, and participants expressed high satisfaction with the protocol, suggesting good acceptability for future studies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Using Transcranial Direct Current Stimulation to Treat Depression in HIV-Infected Persons: The Outcomes of a Feasibility Study. Knotkova, H., Rosedale, M., Strauss, SM., et al.[2021]

In a study involving 62 healthy participants, anodal transcranial direct current stimulation (tDCS) at 2 mA for 20 minutes did not show a significant effect on cortical excitability, suggesting that this method may not reliably enhance brain activity as previously thought.

The study also explored individual factors like BDNF genotype and APLM latency to see if they influenced responses to tDCS, but found no evidence of variability in responses among participants, indicating a lack of identifiable 'responders' to the treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

No effect of anodal tDCS on motor cortical excitability and no evidence for responders in a large double-blind placebo-controlled trial. Jonker, ZD., Gaiser, C., Tulen, JHM., et al.[2021]

In a study involving 19 children and adolescents with dyslexia, transcranial direct current stimulation (tDCS) was found to significantly reduce reading errors during text reading when using a left anodal/right cathodal configuration, indicating a potential therapeutic effect.

The results also showed that the effects of tDCS on reading performance are polarity dependent, suggesting that customizing tDCS parameters could enhance treatment protocols for dyslexia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Reading changes in children and adolescents with dyslexia after transcranial direct current stimulation. Costanzo, F., Varuzza, C., Rossi, S., et al.[2016]

Transcranial current brain stimulation (tCS) techniques, such as tDCS, tACS, and tRNS, use weak electrical currents to influence brain activity noninvasively, with current intensities typically ranging from 0.3 to 5 A/m2.

These methods generate electric fields in the brain that can modulate neuronal activity, and the paper reviews the biophysics behind these interactions, highlighting the need for further research to optimize their therapeutic applications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Transcranial current brain stimulation (tCS): models and technologies. Ruffini, G., Wendling, F., Merlet, I., et al.[2022]

Transcranial direct current stimulation (tDCS) effectively increases beta-frequency power in the brain, indicating a readiness for improved cognitive functioning, as observed in a study with 10 healthy participants.

This study is significant as it is the first to simultaneously apply tDCS while recording EEG, providing insights into the dynamic changes in brain activity during stimulation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Beta-frequency EEG activity increased during transcranial direct current stimulation. Song, M., Shin, Y., Yun, K.[2014]

Microdermabrasion significantly reduced skin resistance by about 32%, allowing for higher doses of transcranial direct current stimulation (tDCS) without increasing skin sensations or device limitations.

The study found that while microdermabrasion increased perceived sensations slightly when not combined with sonication, overall, it enabled safer and more effective delivery of tDCS by lowering the voltage needed to achieve the same current.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Microdermabrasion facilitates direct current stimulation by lowering skin resistance. Chhatbar, PY., Liu, S., Ramakrishnan, V., et al.[2023]

Citations

1. withpower.com withpower.com/trial/phase-dyslexia-11-2022-1af8f

Brain Stimulation for Dyslexia ... RLN real non-invasive brain stimulation intervention will have tolerable side effects & efficacy for patients with Dyslexia and Dyslexia. See if you qualify

2. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/40466912/

A randomized, double-blind, controlled clinical trial The present study aimed to investigate whether tDCS would enhance the reading skills of dyslexic children and whether the effect is long-lasting.

3. clinicaltrials.gov clinicaltrials.gov/study/NCT05832060

Comparing the Efficacy of tDCS and tRNS to Improve ... Transcranial electrical stimulation improves phoneme processing in developmental dyslexia. ... non-invasive brain stimulation. transcranial electrical stimulation.

4. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC12159574/

On the Effects of Non-Invasive Brain Stimulation Techniques ... Conclusion: Research indicates that tDCS, when used with reading interventions, enhances specific reading skills in individuals with dyslexia. Additionally, ...

5. scielo.br scielo.br/j/codas/a/kbSV3xDLGgwwSwRRFMCCNhy/

a scoping review Efficacy of Transcranial Direct Current ... This study aims to improve the existing knowledge about the application of Transcranial Direct Current Stimulation in rehabilitating Developmental Dyslexia.

6. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/35938945/

A systematic review of randomized controlled trials on ... tDCS was found safe with no reported serious side effects in 6587 sessions conducted on 745 children and adolescents across 35 studies.

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6174647/

Impact of Transcranial Direct Current Stimulation on ... Positive results after transcranial direct current stimulation include reduction of epileptic seizures, improvement in static balance and ...

8. frontiersin.org frontiersin.org/journals/neurology/articles/10.3389/fneur.2024.1338430/full

Effects of online tDCS and hf-tRNS on reading ... Previous findings have shown stronger effects of tRNS compared to tDCS on language and learning abilities, including mathematical skills (69), as well as on ...