Effect of tDCS on Motor Functions and Brain Activity in Acute Stroke Patients

Stroke or cerebrovascular accident is a leading cause of disabilities. Physical therapy is a standard treatment to help motor recovery after stroke. However, disabilities remained in some stroke patients despite intensive training. After stroke, there are changes of cortical excitability and brain activity in both hemispheres. Lesioned hemisphere decreases cortical excitability and increases number of low-frequency brain activity, while the non-lesioned hemisphere increases cortical excitability and increases number of high-frequency brain activity. Transcranial direct current stimulation (tDCS) is a technique which delivers weak direct current through scalp and can be used as an adjunctive treatment. Anodal tDCS can increase cortical excitability and amount of high-frequency brain activity. Increased amount of high-frequency brain activity in the lesioned hemisphere can indicate better recovery of stroke. Meta-analysis has reported the benefits of anodal tDCS for motor recovery in stroke patients. However, only few studies have investigated tDCS effects in acute phase of stroke which is a crucial time for enhancing motor recovery. This study aims to investigate the effects of anodal- and cathodal tDCS combined with conventional physical therapy for 5 consecutive sessions on motor functions and brain activity in acute stroke patients at immediate and 1-month follow-up. Participants will be randomly assigned into 2 groups (sham-, and anodal tDCS). Participants in the anodal group will receive 1.5 mA tDCS for 20 minutes before physical therapy programs for 5 consecutive sessions, while the sham group will receive sham tDCS with physical therapy. Brain activity by electroencephalography and motor performances by Fugl-Meyer Assessment and Wolf Motor Function Test will be evaluated at baseline, post-intervention (day 5), and follow-up at 1 month. We hypothesize that anodal tDCS combined with physical therapy for 5 consecutive days can immediately increase number of high-frequency brain activity and improve motor functions and this effect will last for a month compared to the sham group.

Inclusion criteria

• Age between 18-75 years old
• First-ever acute ischemic stroke of anterior circulation system (anterior cerebral artery or middle cerebral artery territory)
• Stroke onset from 2-10 days
• Having a stable medical condition
• Alert of consciousness
• Able to follow commands
• Modified Rankin Scale (mRS) ≤ 4

Exclusion criteria

• Hemorrhagic stroke
• Recurrent stroke
• Presence of other neurological disorders such as unilateral neglect
• Presence of metal implantation, intracranial shunt, cochlear implantation or cardiac pacemakers
• Presence of opened wound or infectious wound around scalp
• History of epilepsy or any neurological antecedent or unstable condition which can lead to seizure
• Body Mass Index (BMI) > 30 kg/m2
• Received hormonal treatment
• Ischemic heart disease and peripheral vascular ischemia
• Last stage of kidney disease and liver disease