Aphasia, Stroke
Conditions
Brief summary
This study will assess the effects of transcranial alternating current stimulation (tACS) on language recovery after stroke.
Detailed 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. 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, potentially with brain stimulation concurrent with therapies. The current study will investigate the efficacy of high-definition tACS (HD-tACS) to help restore neural oscillatory activity in stroke survivors with aphasia. TACS differs from trancranial direct current stimulation (tDCS), a widely used brain stimulation paradigm, in that sinusoidal or alternating currents are delivered rather than direct currents. TACS is shown to manipulate ongoing oscillatory brain activity and also to modulate synchronization (or connectivity) between targeted brain areas. This feature of tACS is quite attractive, given the new body of evidence suggesting that language impairments stem from diminished brain connectivity and ensuing disruptions in the language network due to stroke. The study will employ high-definition tACS (HD-tACS) in a parallel, double-blinded, sham-controlled design combined with language therapy targeting phonological short-term memory (STM) function in stroke survivors with aphasia. Magnetoencephalography (MEG) and fMRI BOLD data collection will occur to determine tACS parameters and to evaluate stimulation-induced neural changes, respectively. The investigators plan to recruit 120 stroke survivors with aphasia in a 2-group tACS study design.
Interventions
DEVICEHD-tACS
High definition tACS will be applied during speech therapy.
DEVICESham HD-tACS
Sham high definition tACS will be applied during speech therapy.
Sponsors
Medical College of Wisconsin
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Diagnosed with left hemisphere stroke/aphasia * Consent date \>= 1 month after stroke onset * 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 * Contraindications to MRI or tACS, e.g. patients with metallic implants, and/or history of skull fractures, pregnancy, skin diseases * History of ongoing or unmanaged seizures * History of dyslexia or other developmental learning disabilities
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Accuracy on a phonological STM task | Upon the completion of therapy cycle (a cycle consists of 10 intervention days) and 10 weeks post | Accuracy changes in a delayed sample-to-match task assessing phonological STM after tACS. |
| fMRI measures of language network activation after tACS | Upon the completion of therapy cycle (a cycle consists of 10 intervention days) and 10 weeks post | Activation in the language network regions involved in phonological STM will be assessed before and after tACS |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Functional Communication Outcome | Upon the completion of therapy cycle (a cycle consists of 10 intervention days) and 10 weeks post | Improvements in using language in daily life or functional communication as assessed by patient reported measure of Communication Effectiveness Index (CETI) |
Countries
United States
Contacts
CONTACTSidney E Schoenrock, MA
CONTACTPriyanka Shah-Basak, PhD
Outcome results
None listed