Brain Activity and Upper Limb Movement Analysis in Individuals With Down Syndrome Undergoing Transcranial Direct Current Stimulation Combined With Virtual Reality Training: Study Protocol for a Longitudinal Randomized Controlled Trial

Background: Children with Down Syndrome have poorer functional and sensory skills compared to children with typical development. Virtual reality training could help improve these skills. Moreover, transcranial direct current stimulation has achieved promising results in terms of enhancing the effects of physical and sensory therapy by modulating cortical excitability. Methods/design The sample will be defined after conducting a pilot study with the same methodology as that to be used in the main study. The study will involve individuals with Down Syndrome with a cognitive age of six to 12 years according to the Wechsler Abbreviated Intelligence Scale. Will be randomly allocated into two groups: Group 1 AtDCS combined with a virtual reality game and a manual motor task. Group 2 sham AtDCS with a virtual reality game and a manual motor task. The training protocol will involve 10 sessions of AtDCS during memory and motor task games. Three 20-minute 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 session 10) and follow-up (one month after the proposed training). The evaluations will consist of an analysis 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 is believed to be related to interactive training 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 individuals. Therefore, the proposed study aims to complement the literature with further information and different variables to provide the scientific community with clinical data on this combination of interventions. Trial Registration: REBEC protocol number RBR-43pk59 registered on 2019/03/27 and Human Ethics Committee number 3.608.521 approved on 2019/09/30.