tDCS and CO-OP in Chronic Stroke

This project seeks to evaluate the acceptability feasibility, practicality feasibility, and preliminary effect of combining transcranial direct current stimulation (tDCS) and metacognitive strategy training (MCST) in individuals with chronic stroke.

Currently seven million people are living in the United States post stroke, making stroke the leading cause of long term disability. Almost half of the people living in the community following stroke have problems that challenge the activities that support their daily lives. This is in part due to the rehabilitation community's focus on short term stroke recovery and not on supporting survivors' need to actively manage their long-term disability and the environment around them so they can return to full participation in communities of their choice post-rehabilitation. The rehabilitation community is in need of evidence-based interventions for addressing post-stroke functional limitations. Metacognitive strategy training is a performance-based, problem-solving approach to task performance difficulties. Participants are taught to identify when to apply a cognitive strategy, how to apply it, and how to monitor and adapt usage of cognitive strategies within task performance. Metacognitive strategy training is recognized as a practice standard for addressing functional limitations post-stroke. Transcranial direct current stimulation is a method that has been used for over 15 years to modulate the excitability of targeted brain regions. While it does not directly stimulate neurons, it results in changes to polarity of neuronal membranes and is thought to facilitate or inhibit neuroplasticity. Combination of these approaches may result in an interaction of effects and a greater effect on function in individuals post-stroke than either approach used alone.

One-hour session three times per week for 4 weeks. Participants will receive anodal tDCS (1.5 mA) to the dorsolateral prefrontal cortex (dlPFC) for 20 minutes at the beginning of each session. Following each tDCS session, the participants will complete a sensations questionnaire.The basis for each session will be task-based practice of client-chosen goals and the use of cognitive strategies using CO-OP.

Transcranial direct current stimulation modulates the excitability of targeted brain regions, and is thought to facilitate or inhibit neuroplasticity. Participants will receive anodal tDCS (1.5 mA) to the dorsolateral prefrontal cortex (dlPFC) for 20 minutes at the beginning of each session. CO-OP focuses on learning of a global problem-solving strategy, Goal-Plan-Do-Check (GPDC), within the performance of participant-chosen goals. Use of a broadly applicable strategy and meaningful activity ensures the intervention is salient to the participant and increases likelihood of transfer. Uniquely, therapists applying CO-OP use guided discovery methods to support participants in analyzing their own performance of a given task and generating potential solutions for improving performance. Participants become equipped with these skills through repetitive application of the Goal-Plan-Do-Check process.The intervention focuses on learning GPDC with gradual withdrawal of guided discovery methods.

Acceptability of Intervention Measure (AIM), Intervention Appropriateness Measure (IAM), & Feasibility of Intervention Measure

A brief questionnaire to evaluate participant satisfaction regarding the intervention's acceptability, appropriateness, and feasibility

A brief interview to gather participant perceptions of the intervention, including their perceived benefit and practicality of the intervention and suggestions for improvement for the intervention.

An objective measure of participant performance of goals. Each goal is rated by a trained observer from 1 (no activity criteria were met) and 10 (all activity criteria were met).

Self-report measures of perceived performance and satisfaction of occupational performance on a 1 to 10 Likert scale

Inclusion Criteria: > 6 months post mild to moderate ischemic stroke self-reported functional limitations Age 30-80 Exclusion Criteria: history of other neurological diagnoses cognitive impairment (less than or equal to 21 on the Montreal Cognitive Assessment) severe aphasia (greater than or equal to 2 on the NIHSS language item non-English speaking any additional condition where the PI deems participation unsafe pregnancy, 7) history of seizures medications that influence cortical excitability metallic implants above the chest history of welding or metalwork severe depressive symptoms (>21 on Patient Health Questionnaire)

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