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

This is a composite measure of verbal expression skills including tests of naming, verbal fluency, sentence completion, and responsive naming (one-word answers to basic questions). It is a subtest within the Western Aphasia Battery. The minimum score is 0 and maximum is 10, with 10 being the best outcome, and subscores are summed to determine the total score.

The above subtests will reflect the following: a composite measure of information content in conversational speech and picture description (scored from 0 (no speech produced or only meaningless utterances) to 10 (no signs of aphasia)); a measure of word and sentence repetition (scored from 0 (unable to repeat any part of a single word) to 100 (perfect repetition of all words and up to a 10 word sentence)); a composite measure of yes/no questions, auditory word recognition, and following sequential commands (composite subscore is from 1 to 10, with 10 being the best outcome); and an overall aphasia severity score (composite score, or Aphasia Quotient, comprised of all the above measures plus the naming and word finding score used as the primary outcome measure. Quotient scores range from 0 to 100, with 100 indicating no aphasia is present).

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. There are 60 items on the test. A score of 0 means no pictures were named correctly. A score of 60 means all pictures were named correctly.

Questionnaires were given at baseline, 3 weeks and 3 months after treatment. The SADQ consists of 21 questions graded on a 0-3 scale with 3 indicating the highest depression symptoms and 0 indicating none. Therefore, means reported below are an average score between 0 and 3. The SAQOL includes 17 questions about functional physical limitations and 7 questions about functional communication limitations in daily life. Questions are rated on a 1-5 scale with a score of 1 indicating greater disability and 5 indicating none. Therefore, means reported below are an average score between 1 and 5. The CETI measures change in functional communication by asking caregivers to make a mark on a straight line with "as able as before the stroke" written on the right side of the line and "not at all as able" on the left. The 16 responses are then converted by measuring the location of the mark on the line. A score of 10 indicates "as able as before the stroke" and 0 indicates "not at all as able".

The following subtests from the CLQT will be administered: Symbol Cancellation, Story Retelling, Generative Naming, 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 (EF), and Visuospatial skills (VS). Some tests are weighted more than others in each composite score, by multiplying the score as follows and then adding the scores together: Attention = Symbol Cancellation (x9), Story Retelling (x2), Symbol Trails (x3), Mazes (x4), and Design Generation (x1); EF = sum of Symbol Trails, Generative Naming, Mazes, and Design Generation; VS = Symbol Cancellation (x2), Symbol Trails (x2), Design Memory (x4), Mazes (x3), Design Generation (x1). For all composite scores, a low number indicates greater deficit. For Attention, the highest score is 215 and lowest is 0. For EF, the highest score is 40 and lowest is 0. For VS, the highest score is 105 and lowest is 0

A set of reading tasks designed to assess oral reading of real words and non-words at the single word level. The list of real words consisted of 142 words. A score of 0 indicates no words were read correctly and a score of 142 indicates all words were read correctly. The non-word test included 30 non-words. A score of 0 indicates no non-words were read correctly and a score of 30 indicates that all non-words were read correctly.

An assessment of upper extremity motor impairment, including: pinch grip, elbow flexion, and shoulder abduction. For pinch grip, which consisted of holding a small plastic cube between the thumb and index finger, scoring was as follows: 0=No movement, 11=Beginnings of prehension, 19=Grips cube but unable to hold against gravity, 22=Grips cube, held against gravity but not against weak pull, 26=Grips cube against pull but weaker than left side, 33=Normal pinch grip. For elbow flexion and shoulder abduction, scoring was as follows: 0=No movement, 9=Palpable contraction in muscle but no movement, 14=Movement seen but not full range/not against gravity, 19=Full range against gravity, not against resistance, 25=Movement against resistance but weaker than left side, 33=Normal power. Both the right and the left side were tested.