Estimulação transcraniana por corrente contínua e treino motor em hemiparéticos: ensaio clínico, cego e controlado

Abstract

Neurological deficits due to stroke vary in intensity and duration of symptoms, being a major cause of disability and withdrawal from work due to sequelae. Hemiparesis is one of the most characteristic. Aim: To investigate the acute effects of transcranial direct current stimulation (tDCS) associated with a simulation of functional training in hemiparetic patients and healthy volunteers. Methods: A total of 5 hemiparetic subjects (GE) were randomly submitted at different times to Conditions A and B. In both conditions, tDCS was associated with a motor training with paretic limb. In Condition Anodal tDCS was applied on affected cerebral hemisphere and on Condition B, cathodal tDCS was applied on not affected hemisphere. In the group of healthy volunteers (GC), 10 healthy subjects, after randomization, were divided between these two conditions. The following tests were used: Box and Block Test (BBT), Nine Hole and Pin test (9HPT), Handgrip Dynamometry and Electroencephalography (EEG) in three different times: T0, baseline, T1 , after tDCS, and T2, after motor training. Results: In functional measurements, we found statistically difference for BBT between T0 and T1 (p = 0.035) and for 9HPT between T0 and T2 (p=0.038). In GC, a statistically significant difference was found between T0 and T2 in 9HPT (p = 0.044). In the electrophysiology, there was a statistically significant difference in GC during motor imagery in the alpha spectrum between T0, T1 and T2 (p = 0.005) and in the beta band between T0 and T2 (p=0.028) in the non-dominant index movement. Conclusion: The proposed protocol was able to create and identify positive responses of tDCS and motor training in manual dexterity in hemiparetic and healthy subjects. We suggest addition of a sham group, to better evaluate isolated contribution of tDCS and motor training.