L, central, centro-parietal, and parietal regions (arranged in a common 100 configurationL, central, centro-parietal, and

L, central, centro-parietal, and parietal regions (arranged in a common 100 configuration
L, central, centro-parietal, and parietal regions (arranged inside a standard 100 configuration), namely, Fz, FC3, FCz, FC4, C5, C3, C1, Cz, C2, C4, C6, CP3, CPz, CP4, P3, Pz, and P4. The left ear mastoid was utilised as a reference electrode when the best ear electrode was utilized as the ground electrode. The surface electrical Safranin References stimulation was delivered using a computer-controlled stimulator (ProStim, MXM, France) with a maximum pulse width (PW) modulation [51] of 400 at a constant amplitude and frequency (20 Hz). Every single stimulation sequence consisted of a trapezoidal envelope train PW (0.four s ramp-up, 1.two s plateau, and 0.4 s ramp-down). Rectangular electrodes of five 9 cm in size have been placed in the anterior compartment of the upper-limbs and the triceps surae muscle group for the lower-limbs to induce a wrist flexion and foot plantar flexion, corresponding for the mental job performed. The electrical stimulation was set by the participants before the start off from the experiment to a comfortable level. Nevertheless, it was ensured that the electrical stimulation did not exceed 25 mA. The EEG recording, display of visual cues, feedback, and online classification from the motor imagery tasks had been conducted utilizing OpenVIBE application [52]. The output on the classifier was sent as a command to the stimulator by means of MATLAB. An offline evaluation for automated ErrP detection was conducted within a Python 3.five atmosphere, the results of which are discussed in Section 3.Brain Sci. 2021, 11,5 of2.2. Participants Sixteen naive participants (13 male and 3 female, using a mean age = 28 9 years) volunteered for this study. Amongst the 16 participants, eight received feedback relating to the electrical stimulation (henceforth, named the FES group), whereas the other eight were offered visual feedback (henceforth, referred to as the VIS group). The choice of participants in the FES and VIS groups was carried out at random. The participants undertook the experiment in isolation even though sitting within a comfortable chair placed in front of a show monitor placed at eye level. The C6 Ceramide In Vitro subjects have been informed in regards to the objective from the experiment as well as the tasks they could be necessary to carry out prior to the start from the experiment. Immediately after this debriefing, if they agreed to continue with the experiment, the participants signed an informed consent form that was previously approved by the institutional (Inria) ethical committee. Following the completion in the experiment, the participants had been asked to provide a subjective assessment of how focused they have been while performing the tasks on scale of 110. two.three. Job Description and Visual Cue The participants performed the cued motor imagery tasks utilizing their left hand, suitable hand, left foot, and correct foot. Every participant in the FES and VIS groups underwent a single education session followed by three feedback sessions. Every session consisted of 24 trials for each motor imagery process. The visual cues (Figure two) have been displayed inside the following sequence. At the beginning of every trial, a fixation cross was displayed on the screen for 1 s. Motor imagery instructions have been then provided for 1 s within the type of arrows. The sequence of arrows was as follows: a left/right arrow to indicate a motor imagery around the left/right side, followed by an up/down arrow to indicate no matter whether to move the hand or foot. For example, if a proper arrow was displayed followed by a down arrow, then the participant will have to consider moving the appropriate foot. The instruction cues have been followed by a feedback.