Repercussions of transcranial direct current stimulation associated with neurofunctional physiotherapy in the electrical brain activity in stroke

Félix, V.1, Brito, R.1, Baltar, A. 1, Shirahige, L. 1, Monte-Silva, K1

1 Laboratório de Neurociência Aplicada – LANA, Universidade Federal de Pernambuco, Brasil

OBJECTIVE: to evaluate the transcranial direct current stimulation (tDCS) associated with neurofunctional physiotherapy on the electrical brain activity of post-stroke patients.

METHODS: randomized clinical trial, double blind, sham-controlled, with 45 patients with stroke. The patients undergo randomly to 10 sessions (5 times/weeks) of: (i) tDCS-anodic in the ipsi-lesional motor cortex (2mA, 20minutes, 0.057mA / cm²); or, (ii) tDCS-sham (2mA, 30 seconds, 0.057mA / cm²). After stimulation, all patients performed 45 minutes of neurofunctional physiotherapy considering the theory of motor learning and the principles of neuroplasticity. The electrical brain activity was assessed by quantitative electroencephalography using the Power Ratio Index (PRI). The PRI is a ratio of slow to fast frequency bands (delta+theta/alpha+beta). The evaluations were carried out before (Baseline) and after the 10 sessions (Revaluation). The results are shown in mean, standard deviation and mean difference (subtraction of revaluation-baseline).

RESULTS: The t-test revealed that anodic tDCS when associated with neurofunctional physiotherapy was not able to modify the cortical electrical activity (Baseline: 2.44±0.30; Revaluation: 2.56±0.42; p=0.17). The same was observed for tDCS sham (Baseline: 2.91±0.55; Revaluation: 3.04±0.39; p=0.46). Additionally, the t-test for independent sample showed a difference between the anodic and sham group at the baseline moment (p < 0.01), remaining after the revaluation (p <0.01). However, it is worth pointing that interpreting through the mean difference, the groups are similar in relation to interventions (anodic: 0.11±0.31; sham: 0.13±0.68; p=0.93).

CONCLUSIONS: tDCS associated with neurofunctional physiotherapy is not able to modify the electrical brain activity of voluntary stroke patients.

TABLE . Power Ratio Index

Mean difference: reassessment - baseline assessment

KEYWORDS: Stroke, tDCS, qEEG, Power Ratio Index


FUNDING/FINANCIAL SUPPORT: This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001