Brain activity and upper limb movement analysis in children with Down syndrome undergoing transcranial direct current stimulation combined with virtual reality training: study protocol for a randomized controlled trial.

BACKGROUND: Children with Down syndrome have poorer functional and sensory skills compared to children with typical development. Virtual reality (VR) training could help improve these skills. Moreover, transcranial direct current stimulation (tDCS) has achieved promising results in terms of enhancing the effects of physical and sensory therapy by modulating cortical excitability. METHODS/DESIGN: Two investigations are proposed: (1) an observational study with a convenience sample consisting of children with Down syndrome (group 1-cognitive age of 6 to 12 years according to the Wechsler Abbreviated Scale of Intelligence) and children with typical development 6 to 12 years of age (group 2). Both groups will undergo evaluations on a single day involving a three-dimensional analysis of upper limb movements, an analysis of muscle activity of the biceps and brachial triceps muscles and an analysis of visuospatial and cognitive-motor variables. (2) Analysis of clinical intervention: a pilot study and clinical trial will be conducted involving individuals with Down syndrome (cognitive age of 6 to 12 years according to the Wechsler Abbreviated Scale of Intelligence). The sample will be defined after conducting a pilot study with the same methodology as that to be used in the main study. The participants will be randomly allocated to two groups: An experimental group submitted to anodal tDCS combined with a VR game and a manual motor task and a control group submitted to sham tDCS combined with a VR game and a manual motor task. The training protocol will involve 10 sessions of active or sham tDCS during memory and motor task games. Three 20-min sessions will be held per week for a total of 10 sessions. Evaluations will be performed on three different occasions: pre-intervention, post-intervention (after 10 sessions) and follow-up (1 month after the intervention). Evaluations will consist of analyses of electroencephalographic signals, electromyographic signals of the biceps and triceps brachii, and the three-dimensional reconstruction of the reaching movement. The results will be analyzed statistically with the significance level set at 5% (p ≤ 0.05). DISCUSSION: The optimization of the results obtained with virtual reality training is believed to be related to the interactive experience with a wide range of activities and scenarios involving multiple sensory channels and the creation of exercises, the intensity of which can be adjusted to the needs of children. Therefore, the proposed study aims to complement the literature with further information on tDCS and VR training considering different variables to provide the scientific community with clinical data on this combination of interventions. TRIAL REGISTRATION: Brazilian Clinical Trials Registry (REBEC) protocol number RBR-43pk59 registered on 2019 March 27 https://ensaiosclinicos.gov.br/rg/RBR-43pk59 and Human Research Ethics Committee number 3.608.521 approved on 2019 September 30. Protocol version 2021 October 20. Any changes to the protocol will be reported to the committees and approved. Informed consent will be obtained from all participants by the clinical research coordinator and principal investigator.

tDCS and motor training in individuals with central nervous system disease: A systematic review.

BACKGROUND: Transcranial direct current stimulation (tDCS) is a promising tool for patients with neurological disorders, as it increases cortical excitability, motor learning and functionality. The studies up to date have focused on the tDCS parameters while the effects of the motor training have not yet been fully addressed. The purpose of this study is to present a systematic review of all studies related to tDCS in conjunction with motor training (MT) to improve gait performance, functionality, mobility and balance in individuals with non-progressive central nervous system diseases. METHODS: Seven databases were searched for articles from inception to October 2018. The search strategy followed Collaboration guidelines. The Physiotherapy Evidence Database (PEDro) Scale and Cochrane Collaboration's tool for assessing the risk of bias were applied to evaluate methodological quality. RESULTS: Four hundred and sixteen recorded were screened. Ten studies met the inclusion criteria. All studies were randomized controlled trials, two of them had a crossover design and other two were pilot studies. Three paper analyzed children and adolescents with cerebral palsy, seven papers analyzed adults and elderly post stroke. tDCS with MT lead to significant results. CONCLUSIONS: This review found limited evidence for the use of tDCS with MT for in children with CP and adults post stroke, due to the small number of studies as well as their methodological heterogeneity. In the absence of more robust evidence, further studies with a consistent methodological design are needed to endorse the clinical application of tDCS with motor training.