Single Session of Dual-tDCS Transiently Improves Precision Grip and Dexterity of the Paretic Hand After Stroke. (February 2014)

• Record Type: Journal Article
• Authors: Lefebvre, Stéphanie; Thonnard, Jean-Louis; Laloux, Patrice; Peeters, André; Jamart, Jacques; Vandermeeren, Yves
• Is Part Of: Neurorehabilitation & neural repair. Volume 28:Number 2(2014)
• Page Start: 100
• Page End: 110
• Publication Date: 2014-02
• Subjects: transcranial direct current stimulation -- precision grip -- Purdue Pegboard Test -- stroke rehabilitation -- repetitive transcranial magnetic stimulation; Nervous system -- Diseases -- Patients -- Rehabilitation -- Periodicals; Brain damage -- Patients -- Rehabilitation -- Periodicals; Spinal cord -- Wounds and injuries -- Patients -- Rehabilitation -- Periodicals; Nervous system -- Regeneration -- Periodicals; Neuroplasticity -- Periodicals; 616.804305
• DOI: 10.1177/1545968313478485
• Languages: English
• ISSNs: 1545-9683

Abstract

Background . After stroke, deregulated interhemispheric interactions influence residual paretic hand function. Anodal or cathodal transcranial direct current stimulation (tDCS) can rebalance these abnormal interhemispheric interactions and improve motor function. Objective . We explored whether dual-hemisphere tDCS (dual-tDCS) in participants with chronic stroke can improve fine hand motor function in 2 important aspects: precision grip and dexterity. Methods . In all, 19 chronic hemiparetic individuals with mild to moderate impairment participated in a double-blind, randomized trial. During 2 separate cross-over sessions (real/sham), they performed 10 precision grip movements with a manipulandum and the Purdue Pegboard Test (PPT) before, during, immediately after, and 20 minutes after dual-tDCS applied simultaneously over the ipsilesional (anodal) and contralateral (cathodal) primary motor cortices. Results . The precision grip performed with the paretic hand improved significantly 20 minutes after dual-tDCS, with reduction of the grip force/load force ratio by 7% and in the preloading phase duration by 18% when compared with sham. The dexterity of the paretic hand started improving during dual-tDCS and culminated 20 minutes after the end of dual-tDCS (PPT score +38% vs +5% after sham). The maximal improvements in precision grip and dexterity were observed 20 minutes after dual-tDCS. These improvements correlated negatively with residual hand function quantified with ABILHAND. Conclusions . One bout of dual-tDCS improved the motor control of precision grip and digital dexterity beyond the time of stimulation. These results suggest that dual-tDCS should be tested in longer protocols for neurorehabilitation and with moderate to severely impaired patients. The precise timing of stimulation after stroke onset and associated training should be defined.