Transcranial Alternating Current Stimulation (tACS) in Aphasia
Aphasia, Stroke
About this trial
This is an interventional treatment trial for Aphasia focused on measuring language, language impairment, transcranial alternating current stimulation, tACS
Eligibility Criteria
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
Sites / Locations
- Medical College of WisconsinRecruiting
Arms of the Study
Arm 1
Arm 2
Arm 3
Experimental
Experimental
Sham Comparator
tACS 10 Hz low frequency
tACS 40 Hz high frequency
tACS sham
High-Definition-tACS will be 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 10-Hz stimulation for 20-minutes with 1 milliampere (mA) peak-to-peak intensity. Stimulation will be maintained no longer than 20 minutes.
High-Definition-tACS will be 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 40-Hz stimulation for 20-minutes with 1 milliampere (mA) peak-to-peak intensity. Stimulation will be maintained no longer than 20 minutes.
High-Definition-tACS will be 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 for 10 to 30 seconds and then ramped down. In this way, the participants experience the same initial sensations (mild tingling) as the active tACS groups.