Treatment Outcomes With tDCS in Post-Stroke Aphasia
Treatment Outcomes With tDCS in Post-Stroke Aphasia
The purpose this study is to test the utility of pairing external neuromodulation with
 behavioral language treatment to boost therapy outcomes and to investigate the mechanisms
 associated with recovery. Because all PWA have word retrieval deficits, this project will
 test if greater language gains can be achieved by supplementing anomia intervention with
 excitatory brain stimulation to the left hemisphere and will evaluate associated functional
 brain changes to aid the optimization of neural reorganization to facilitate language
 processing.
Aphasia is a language impairment that commonly occurs following brain damage (e.g., stroke).
 While language rehabilitation can yield improved language functioning, treatment outcomes
 vary greatly across individuals. In chronic aphasia, language gains occur through the brain's
 inherent ability to reorganize (i.e., neuroplasticity).

 While Speech-language therapy (SLT) can target various language skills and modalities, the
 most pervasive deficit across all persons with aphasia (PWA) is difficulty with word finding.
 Thus, aphasia treatment often includes some form of intervention focused on improving naming
 abilities. As with language function in general, naming abilities in PWA seems to be
 associated with left hemisphere recruitment, particularly with the viable tissue at the rim
 of the lesion (perilesional areas). This project investigates an innovative approach to
 improving current therapy by examining the benefits of using excitatory transcranial direct
 current stimulation (tDCS) stimulation/neuromodulation during anomia treatment (i.e.
 word-finding treatment).

 This study investigates an innovative approach to improving current therapy by examining the
 benefits of using excitatory tDCS stimulation/neuromodulation during anomia treatment. This
 project will provide novel mechanistic understanding of changes in functional brain
 connectivity in persons with post-stroke aphasia and how connectivity relates to treatment
 outcomes.

 The aims of this study are as follows:

 Aim 1. To investigate the benefits of using broad transcranial direct current stimulation
 (tDCS) to improve word retrieval in persons with aphasia (PWA). Aim 2. To study functional
 brain changes related to this treatment. Aim 3. To examine behavioral and neural
 re-organization correlates related to treatment outcomes.

 All participants will complete the following 3 components: (1) Baseline Assessment, (2)
 Interventions (i.e., SLT with active tDCS & sham tDCS , and (3) Outcome Testing (i.e.,
 Behavioral & Brain Imaging). During the first week, each participant will complete all of the
 Neuropsychological Testing Battery and the first round of the outcome measures as pre-testing
 before starting SLT. Then the participant will complete 2 weeks of SLT accompanied with
 either active tDCS or sham tDCS. Once the SLT is completed, the participant will complete
 round 2 of outcome testing (i.e., post-testing for 1st SLT phase and pre-testing for 2nd SLT
 phase). Then, the participant will complete another 2 weeks of SLT but with the other tDCS
 condition. Once SLT is completed, the participant will complete round 3 of outcome testing
 (i.e., post-testing for 2nd SLT phase). Lastly, the participant will complete round 4 of
 outcome testing (i.e., follow-up)
Inclusion Criteria:

 -  Presence of post-stroke aphasia

 -  Single left hemisphere stroke etiology

 -  At least 6 months post-stroke

 -  Age range between 18 and 80 years old

 -  Speak English as a native language

 -  Adequate hearing and vision to complete the tasks

 Exclusion Criteria:

 -  Severe auditory comprehension deficits (determined by pretest) (i.e., global aphasia,
 Wernicke's aphasia, transcortical sensory aphasia)

 -  Inability to provide informed consent

 -  Co-occurring history of neurological disease/disorder/injury (e.g., traumatic brain
 injury, right hemisphere stroke, dementia)

 -  Co-occurring history of a major mental illness (e.g., schizophrenia, drug addiction,
 bipolar)

 -  Clinical conditions contraindicated for MRI or tDCS (e.g., implanted electrical
 devices, claustrophobia, seizure disorder)

 -  Positive pregnancy test (for females)