Effect of transcranial direct current stimulation on brain connectivity during the first weeks after stroke

Abstract

Background: Stroke is one of the leading causes of long-term disability in Brazil and worldwide. A significant portion of the patients do not recover completely from upper limb paresis, the most common impairment. Non-invasive neuromodulation interventions such as Transcranial Current Stimulation (tDCS) have been developed to potentiate brain plasticity and allow more effective motor recovery. However, the effects of tDCS on brain connectivity in the first weeks post-stroke are poorly understood. Objectives: To compare the effects of 6 sessions of active cathodic tDCS or placebo on the connectivity between the contralesional primary motor cortex and the ipsilesional motor cortex. Methods: Resting state functional magnetic resonance imaging (rsfMRI) of 15 patients with upper limb paresis who underwent cathodal tDCS of the unaffected hemisphere between 3 days and 6 weeks post-stroke were collected in the study "Safety of transcranial direct current stimulation in the subacute stage after ischemic stroke". The connectivity data of seven patients in the active group and eight patients in the placebo group will be compared using the matlab-based cross-platform software - CONN (functional connectivity toolbox).