Effects of Transcranial Direct Current Stimulation in Post-stroke Aphasia
Study Details
Study Description
Brief Summary
This study aims to determine whether transcranial direct current stimulation (tDCS) paired with speech-language therapy is more beneficial than speech-language therapy alone in acute and chronic post-stroke aphasia.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
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N/A |
Detailed Description
This study aims to determine whether behavioral word-retrieval therapy coupled with anodal tDCS will improve the fluency and name retrieval performance of participants with post-stroke aphasia more efficiently and for greater duration than language therapy alone (i.e. in the sham condition).
tDCS neuronal targets will be selected in this order:
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left posterior superior-middle temporal gyrus (an area critical for word retrieval and word comprehension),
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left posterior frontal areas found to be responsible for lexical selection if the first area is infarcted, or
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right cerebellum (important for learning, and consistently activated in naming task) if both of the other areas are infarcted.
The same areas will be stimulated during the first tDCS and sham periods. If the participant returns for a second period of tDCS and sham with language therapy, the right cerebellum will be stimulated (if it was the only uninfarcted target area investigators will stimulate this area again). For cerebellar stimulation, either anodal or cathodal will be used as studies show that anodal or cathodal stimulation has an effect on cognitive functions.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Active tDCS plus Speech-Language Therapy Active tDCS will be applied at the beginning of 45min speech-language therapy session and will last for 20 min. Language therapy will be oral and written naming. This is a cross-over study so all participants will receive this arm but the order will be randomized. |
Device: Active tDCS plus Speech-Language Therapy
Stimulation will be delivered by a battery-driven constant current stimulator. The electrical current will be administered to a pre-specified region of the brain not affected by the lesion(perilesional areas, right hemisphere or cerebellum). The stimulation will be delivered at an intensity of 2mA (estimated current density 0.04 mA/cm2; estimated total charge 0.048C/cm2) in a ramp-like fashion for a maximum of 20 minutes. Speech-language therapy will be oral and written naming.
Other Names:
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| Sham Comparator: Sham plus Speech-Language Therapy Sham tDCS will be applied at the beginning of 45min speech-language therapy session. Language therapy will be oral and written naming. This is a cross-over study so all participants will receive this arm but the order will be randomized. |
Device: Sham plus Speech-Language Therapy
Speech-Language therapy will be administered during sham stimulation. Current will be administered in a ramp-line fashion but after the ramping the intensity will drop to 0 mA. Speech-language therapy will be oral and written naming.
Other Names:
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Outcome Measures
Primary Outcome Measures
- Change in picture naming scores in trained and untrained items [Before and after 15 sessions of intervention (3 weeks) and at 2 weeks and 2 months follow-ups]
Secondary Outcome Measures
- Change in Philadelphia Naming Test: Picture naming of everyday objects, different from training set [Before and after 15 sessions of intervention (3 weeks) and at 2 weeks and 2 months follow-ups]
- Change in Written naming of objects and actions [Before and after 15 sessions of intervention (3 weeks) and at 2 weeks and 2 months follow-ups]
The investigators will evaluate the absolute number as well as the percent change of the list of objects and actions assigned for intervention as trained and untrained items.
- Change in working memory (digit span) [Before and after 15 sessions of intervention (3 weeks) and at 2 weeks and 2 months follow-ups]
- Change in verbal fluency [Before and after 15 sessions of intervention (3 weeks) and at 2 weeks and 2 months follow-ups]
The investigators will use letter (F, A, S) and semantic fluency measures (animals, fruits and vegetables) and the investigators will measure how many were added or omitted at follow-up intervals.
Eligibility Criteria
Criteria
Inclusion Criteria:
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Clinically diagnosed with with post-stroke aphasia and word-retrieval deficits
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Premorbid speakers of English
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Diagnosis will be based on neuropsychological testing, language testing (most commonly the Western Aphasia Battery), MRI and clinical assessment
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Stroke size: any l
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Location: Left hemisphere strokes only from any etiology.
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Time since stroke onset: 1 day to 20 years.
Exclusion Criteria:
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uncorrected visual or hearing impairment by self report
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other premorbid neurological disorder affecting the brain
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any other language-based learning disorder or other neurodegenerative disorder such as Alzheimer's Disease or Primary Progressive Aphasia
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premorbidly diagnosed with a developmental language disorder
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Pregnant women will also be excluded
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Johns Hopkins Medicine | Baltimore | Maryland | United States | 21287 |
Sponsors and Collaborators
- Johns Hopkins University
Investigators
None specified.Study Documents (Full-Text)
None provided.More Information
Publications
- Dmochowski JP, Datta A, Huang Y, Richardson JD, Bikson M, Fridriksson J, Parra LC. Targeted transcranial direct current stimulation for rehabilitation after stroke. Neuroimage. 2013 Jul 15;75:12-19. doi: 10.1016/j.neuroimage.2013.02.049. Epub 2013 Mar 5.
- Schlaug G, Marchina S, Wan CY. The use of non-invasive brain stimulation techniques to facilitate recovery from post-stroke aphasia. Neuropsychol Rev. 2011 Sep;21(3):288-301. doi: 10.1007/s11065-011-9181-y. Epub 2011 Aug 14. Review.
- NA00078932