Effect of transcranial direct-current stimulation (TDCs) on postural control of children with typical development

Abstract

The Cerebellum controls balance and posture by comparing motor planning and motor execution, and by performing online movement corrections. The Transcranial Direct Current Stimulation (TDCs) is a safe, non-invasive and painless neuromodulatory technique that changes cortical excitability; anodal TDCs has facilitatory effects, while cathodal TDCs causes inhibition. The neurofunctional effects of TDCs on postural control of healthy adults has already been studied. Cerebellar TDCs has also been used to improve postural control of individuals with neurologic impairment, including children with cerebellar dysfunction. Nevertheless, the effects of cerebellar TDCs on postural control of healthy children was not studied. The aim of the present study is to describe the effects of anodal and cathodal cerebellar TDCs on postural control of children with typical development, in comparison with sham TDCs. This is a single blind randomized placebo-controlled clinical trial with cross-over. Twenty children of both genders, aging between 7 and 10 years, without motor difficulties (more than 49% on Movement Assessment Battery for Children 2), will be randomly allocated for anodal, cathodal or sham cerebellar TDCs (TCT - tDCS simulator®). Active anodal or cathodal stimulation with be performed with 1mA for 20 minutes; sham stimulation will be composed of 1mA for 30 seconds and 0 mA until it reach 20 minutes . Postural control will be assessed using a force platform (EMG System - Brasil) immediately before and after anodal, cathodal or sham TDCs in the following conditions: bipodal standing with the eyes opened; bipodal standing with the eyes closed; bipodal standing on foam with the eyes opened; bipodal standing on foam with the eyes closed. Three measures of 30 seconds in each condition will be performed. The mean area, amplitude and velocity of the center of pressure on anteroposterior and mediolateral directions will be analyzed. After an interval of at least one week, the subjects will be submitted to the cross-over. Data will be analysed by comparison of means with repeated measures analysis of variance (ANOVA), considering significance level below 0,05. (AU)