Transcranial Alternating Current Stimulation (tACS) in Aphasia

Stroke Clinical Trial

Official title:

Exogenous Tuning of Neural Oscillations as a Mode of Treatment in Post-stroke Aphasia

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT04375722
• Other study ID #: 36878
• Status: Recruiting
• Phase: N/A
• Start date: January 4, 2020
• Est. completion date: January 2025

Study information

• Verified date: September 2022
• Source: Medical College of Wisconsin
• Contact: Samantha Drane, MS
• Phone: 414-955-5891
• Email: sdrane[@]mcw.edu
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study will assess the effects of transcranial alternating current stimulation (tACS) on language recovery after stroke as well as healthy language functions.

Description:

Aphasia is a debilitating disorder, typically resulting from damage to the left hemisphere, that can impair a range of communication abilities, including language production and comprehension, reading, and writing. Approximately 180,000 new cases of aphasia are identified per year, and approximately 1 million or 1 in 250 are living with aphasia in the United States (NIH-NIDCD, 2015). Treatments are limited and provide modest benefits at best. The current emphasis in aphasia rehabilitation is to formulate intensive speech and language therapies and augment therapeutic benefits by providing brain stimulation concurrent with therapies. Transcranial direct current stimulation (tDCS) is one of the most widely used such technique. While tDCS has had relative success in chronic aphasia (>6 months after stroke), it has not been efficacious during subacute stages (<3 months after stroke). But enhancing language recovery early after stroke is desirable because of its potential impact on long-term language outcomes and quality-of-life.

The current study will investigate the efficacy of high-definition tACS (HD-tACS) to help restore neural oscillatory activity in aphasia. TACS differs from tDCS in that sinusoidal, alternating currents are delivered rather than constant currents. TACS can manipulate the ongoing oscillatory neuronal activity and potentially increase functional synchronization (or connectivity) between targeted areas. This feature of tACS is quite attractive, given the new body of evidence suggesting that language impairments stem from diminished functional connectivity and disruptions in the language network due to stroke. The selection of tACS frequencies in this study is guided by our preliminary work examining pathological neural oscillations found near stroke-lesioned areas (or perilesional) in aphasia. By exogenously tuning the perilesional oscillations with tACS, the investigators hope to up-regulate communication across these areas and other connected areas to improve language outcome. If successful, tACS will be a powerful and novel treatment approach with reverberating positive impact on long-term recovery.

The study will employ HD-tACS in a within-subject and sham-controlled design, using two frequencies (alpha/10 Hz and low-gamma/40 Hz) combined with language tasks and electroencephalography (EEG) to evaluate subsequent behavioral and neurophysiological changes. Investigators plan to recruit 50 participants: 25 stroke survivors with aphasia at lease 1 month after stroke, and 25 healthy controls.

Participants will complete language testing that covers a broad range of language functions, medical history, and MRI. Eligible participants will undergo active tACS at 10 Hz or 40 Hz, or sham-tACS. All participants will receive all three stimulation types during separate visits. The tACS administrator and participants will be blinded to the stimulation type. The order of stimulation type will be counterbalanced across participants. Washout period between visits will be at least 48 hours to minimize potential carryover effects. EEG will be acquired before and after tACS during periods of rest (resting-state) and during language tasks. Participants will complete a questionnaire at the end of stimulation visits to assess potential side effects of tACS. Total time enrolled in the study is expected to be 2-3 weeks, which may be longer depending on participant's availability.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 50
• Est. completion date: January 2025
• Est. primary completion date: January 2025
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 85 Years

Eligibility

Inclusion Criteria:

Healthy Controls

• 18 years of age or older

• Fluent in English

• No history of neurological or psychiatric disorders

Stroke Patients

• Diagnosed with post-stroke aphasia by referring physician/neuropsychologist

• Consent date >=1 months after stroke onset

• Right-handed

• Fluent in English

• 18 years of age or older

Exclusion Criteria:

• Severe cognitive, auditory or visual impairments that would preclude cognitive and language testing

• Presence of major untreated or unstable psychiatric disease

• A chronic medical condition that is not treated or is unstable

• The presence of cardiac stimulators or pacemakers

• Any metal implants in the skull

• Contraindications to MRI or tACS

• History of seizures

• History of dyslexia or other developmental learning disabilities

Related Conditions & MeSH terms

• Aphasia
• Stroke

Intervention

Device:
• tACS 10-Hz
Low frequency alternating current will be applied.
• tACS 40-Hz
High frequency alternating current will be applied.
• tACS sham
Sham stimulation setting will be applied.

Locations

Country	Name	City	State
United States	Medical College of Wisconsin	Milwaukee	Wisconsin

Sponsors (1)

Lead Sponsor	Collaborator
Medical College of Wisconsin

Country where clinical trial is conducted

United States, 

References & Publications (16)

Antal A, Alekseichuk I, Bikson M, Brockmöller J, Brunoni AR, Chen R, Cohen LG, Dowthwaite G, Ellrich J, Flöel A, Fregni F, George MS, Hamilton R, Haueisen J, Herrmann CS, Hummel FC, Lefaucheur JP, Liebetanz D, Loo CK, McCaig CD, Miniussi C, Miranda PC, Moliadze V, Nitsche MA, Nowak R, Padberg F, Pascual-Leone A, Poppendieck W, Priori A, Rossi S, Rossini PM, Rothwell J, Rueger MA, Ruffini G, Schellhorn K, Siebner HR, Ugawa Y, Wexler A, Ziemann U, Hallett M, Paulus W. Low intensity transcranial electric stimulation: Safety, ethical, legal regulatory and application guidelines. Clin Neurophysiol. 2017 Sep;128(9):1774-1809. doi: 10.1016/j.clinph.2017.06.001. Epub 2017 Jun 19. Review. — View Citation

Bucur M, Papagno C. Are transcranial brain stimulation effects long-lasting in post-stroke aphasia? A comparative systematic review and meta-analysis on naming performance. Neurosci Biobehav Rev. 2019 Jul;102:264-289. doi: 10.1016/j.neubiorev.2019.04.019. Epub 2019 May 8. — View Citation

Buzsaki, G. (2006). Rhythms of the brain. New York: Oxford.

Chu RK, Braun AR, Meltzer JA. MEG-based detection and localization of perilesional dysfunction in chronic stroke. Neuroimage Clin. 2015 Apr 8;8:157-69. doi: 10.1016/j.nicl.2015.03.019. eCollection 2015. — View Citation

Dubovik S, Ptak R, Aboulafia T, Magnin C, Gillabert N, Allet L, Pignat JM, Schnider A, Guggisberg AG. EEG alpha band synchrony predicts cognitive and motor performance in patients with ischemic stroke. Behav Neurol. 2013;26(3):187-9. doi: 10.3233/BEN-2012-129007. — View Citation

Finnigan S, van Putten MJ. EEG in ischaemic stroke: quantitative EEG can uniquely inform (sub-)acute prognoses and clinical management. Clin Neurophysiol. 2013 Jan;124(1):10-9. doi: 10.1016/j.clinph.2012.07.003. Epub 2012 Aug 2. Review. — View Citation

Finnigan SP, Walsh M, Rose SE, Chalk JB. Quantitative EEG indices of sub-acute ischaemic stroke correlate with clinical outcomes. Clin Neurophysiol. 2007 Nov;118(11):2525-32. Epub 2007 Sep 21. — View Citation

Fridriksson J, Rorden C, Elm J, Sen S, George MS, Bonilha L. Transcranial Direct Current Stimulation vs Sham Stimulation to Treat Aphasia After Stroke: A Randomized Clinical Trial. JAMA Neurol. 2018 Dec 1;75(12):1470-1476. doi: 10.1001/jamaneurol.2018.2287. — View Citation

Fries P. Rhythms for Cognition: Communication through Coherence. Neuron. 2015 Oct 7;88(1):220-35. doi: 10.1016/j.neuron.2015.09.034. Review. — View Citation

Grefkes C, Fink GR. Reorganization of cerebral networks after stroke: new insights from neuroimaging with connectivity approaches. Brain. 2011 May;134(Pt 5):1264-76. doi: 10.1093/brain/awr033. Epub 2011 Mar 16. Review. — View Citation

Helfrich RF, Schneider TR, Rach S, Trautmann-Lengsfeld SA, Engel AK, Herrmann CS. Entrainment of brain oscillations by transcranial alternating current stimulation. Curr Biol. 2014 Feb 3;24(3):333-9. doi: 10.1016/j.cub.2013.12.041. Epub 2014 Jan 23. — View Citation

Herrmann CS, Rach S, Neuling T, Strüber D. Transcranial alternating current stimulation: a review of the underlying mechanisms and modulation of cognitive processes. Front Hum Neurosci. 2013 Jun 14;7:279. doi: 10.3389/fnhum.2013.00279. eCollection 2013. — View Citation

Kielar A, Deschamps T, Chu RK, Jokel R, Khatamian YB, Chen JJ, Meltzer JA. Identifying Dysfunctional Cortex: Dissociable Effects of Stroke and Aging on Resting State Dynamics in MEG and fMRI. Front Aging Neurosci. 2016 Mar 3;8:40. doi: 10.3389/fnagi.2016.00040. eCollection 2016. — View Citation

Shah-Basak PP, Kielar A, Deschamps T, Verhoeff NP, Jokel R, Meltzer J. Spontaneous oscillatory markers of cognitive status in two forms of dementia. Hum Brain Mapp. 2019 Apr 1;40(5):1594-1607. doi: 10.1002/hbm.24470. Epub 2018 Nov 12. — View Citation

Shah-Basak PP, Norise C, Garcia G, Torres J, Faseyitan O, Hamilton RH. Individualized treatment with transcranial direct current stimulation in patients with chronic non-fluent aphasia due to stroke. Front Hum Neurosci. 2015 Apr 21;9:201. doi: 10.3389/fnhum.2015.00201. eCollection 2015. — View Citation

Shah-Basak PP, Wurzman R, Purcell JB, Gervits F, Hamilton R. Fields or flows? A comparative metaanalysis of transcranial magnetic and direct current stimulation to treat post-stroke aphasia. Restor Neurol Neurosci. 2016 May 2;34(4):537-58. doi: 10.3233/RNN-150616. Review. — View Citation

* Note: There are 16 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	tACS frequency-dependent changes in language performance on object and action naming tasks	Improvement on noun and verb retrieval performance as determined by increases in accuracy and decreases in reaction time.	Immediate changes monitored after 20 minutes of tACS of each type
Primary	tACS frequency-dependent neurophysiological changes	Concomitant frequency-specific EEG changes in spectral power and phase synchronization are expected.	Immediate changes monitored after 20 minutes of tACS of each type
Secondary	Individual differences in tACS responsiveness	tACS responsiveness depending on language impairment types, stroke lesion and language lateralization characteristics will be explored.	Based on immediate changes monitored after 20 minutes of tACS of each type