Using Transcranial Direct Current Stimulation (tDCS) to Improve Post-Stroke Aphasia

• Western Aphasia Battery - Revised: Naming and Word Finding score [ Time Frame: Change from baseline to one day after treatment ] [ Designated as safety issue: No ]
  This is a composite measure of verbal expression skills including tests of naming, verbal fluency, and sentence completion.
  
  

• Western Aphasia Battery - Revised: Spontaneous Speech, Repetition, Auditory Verbal Comprehension and overall Aphasia Quotient [ Time Frame: Immediately; 2 weeks post-treatment; 12 weeks post-treatment ] [ Designated as safety issue: No ]
  The above subtests will reflect the following: a composite measure of information content in conversational speech and picture description; a measure of word and sentence repetition; a composite measure of yes/no questions, auditory word recognition, and following sequential commands; and an overall aphasia severity score.
  
  
• Philadelphia Naming Test (PNT) [ Time Frame: Immediately; 2 weeks post-treatment; 12 weeks post-treatment ] [ Designated as safety issue: No ]
  A test of picture naming using more common items than other picture naming tests, which reduces relationships between performance and premorbid education and socioeconomic status.
  
  
• Boston Diagnostic Aphasia Examination (BDAE): Verbal agility subtest [ Time Frame: Immediately; 2 weeks post-treatment; 12 weeks post-treatment ] [ Designated as safety issue: No ]
  A measure of annunciation to assess the impact of tDCS on slurring of speech and verbal apraxia.
  
  
• Subjective assessments including: Communicative Effectiveness Index, Stroke and Aphasia Quality of Life Scale, and Stroke Aphasic Depression Questionnaire [ Time Frame: Immediately; 2 weeks post-treatment; 12 weeks post-treatment ] [ Designated as safety issue: No ]
  A set of questionnaires to be administered to subjects and immediate family members in order to assess the impact of language impairments on functional communication skills and overall quality of life.
  
  
• Cognitive-Linguistic Quick Test (CLQT) [ Time Frame: Immediately; 2 weeks post-treatment; 12 weeks post-treatment ] [ Designated as safety issue: No ]
  The following subtests from the CLQT will be administered: Symbol Cancellation, Story Retelling, Symbol Trails, Design Memory, Mazes,and Design Generation. These scores will be used to calculate composite scores for the cognitive domains of attention, executive function, and visuospatial skills.
  
  
• Reading assessments [ Time Frame: Immediately; 2 weeks post-treatment; 12 weeks post-treatment ] [ Designated as safety issue: No ]
  A set of reading tasks designed to assess oral reading of real words and non-words at the single word level.
  
  
• Motricity Index [ Time Frame: Immediately; 2 weeks post-treatment; 12 weeks post-treatment ] [ Designated as safety issue: No ]
  An assessment of upper extremity motor impairment, including: pinch grip, elbow flexion, and shoulder abduction.
  
  

This study tests whether aphasia or alexia, language and reading disorders occurring after traumatic brain injury or stroke, can be improved using transcranial direct current stimulation (tDCS). tDCS is a non-invasive technique that applies a small amount of direct electrical current to the brain in order to temporarily alter brain processing. Adults with aphasia/alexia resulting from stroke or traumatic brain injury will undergo baseline behavioral testing of various language and cognitive functions. Subjects who are willing to undergo MRI evaluation will also be scanned. They will then receive five days of either real or sham tDCS with standardized speech-language therapy, under a double-blind randomized placebo-controlled design. Behavioral assessments, and MRIs for those participating in the MRI portion of the study, will be performed again at multiple time points after completing tDCS to assess for changes in these measures.