Clinical Research Directory

tDCS will be delivered using an electrical stimulation device d (1X1 tES, Soterix Medical Inc., USA, CE marked) delivering a direct current at 2 mA for a period of 20 minutes. Silicone electrodes are placed in sponges soaked in physiological saline (5 cm × 7 cm) (EASYpadTM, Soterix Medical Inc.), with the anode and cathode centered on the optimal cortical areas determined during testing visits.

tSCS will be applied for 20 minutes using a constant current electrical stimulator (DS5 or DS7A, Digitimer Ltd, CE marked) delivering monophasic pulses at 30 Hz at stimulation sites and intensities specific to each participant and defined in advance during testing visits.

For the sham stimulation interventions, the current slowly increases to the intensity used during the active interventions for 30 seconds, then slowly decreases over the next 30 seconds, at the beginning and end of the stimulation. The sham interventions use the same electrode placements as during the active ones for a total duration of 20 min.

The cognitive-motor task will be administered using the ArmeoControl software supplied with the ArmeoSping® or ArmeoPower® upper limb rehabilitation exoskeleton. Participants will be seated in a chair or their wheelchair and fitted into the exoskeleton.The exoskeleton is linked to a series of exercises performed on a computer via a virtual reality interface (ArmeoControl), which allows simultaneous training of the arms and hands in a large workspace. Two vertical and horizontal "visually guided reaching" tasks will be offered, each lasting 10 minutes. These tasks are chosen to provide training in cognitive-motor functions (grabbing a target moving in a virtual workspace) and sensorimotor functions (interacting with the exoskeleton to move the target).