The two balls was recorded, and the number of ball rotations was counted. Then, we removed the set, and instructed the participants to start over again if they dropped the ball. Due to the possibility of shifting the stimulation site, the participant was instructed not to pronate or supinate the forearm or flex or extend the wrist from a starting position during the BR task. Experimental procedure Participants were seated in a reclining chair. The stimulator was placed on the ventral side of the wrist joint and fixed with Velcro. Participants rested with their forearms on a table placed to their right. The first part of the experiment recorded resting SEPs for 2 min (rest). Then, SEPs were recorded at a set of 1 and 2 during the BR task.
Also, SEPs were recorded at sets of 11 and 12 during the BR task (post) after the participants practiced the BR task for 8 sets (Figure 1). The participants were stimulated at Spain phone number list approximately 120 per set. The stimulation was delivered 240 times in pre or post. Figure 1 frontiersin.org Figure 1. The BR task was carried out 12 sets in total. The mean of the first two sets is defined as pre. The mean of the last two sets is defined as post. Recording and analysis The Neuropack system was used for all electrophysiological recording.
The electroencephalography (EEG) was measured using Ag/AgCl electrodes placed over three scalp sites, F3, C3′ (2 cm posterior to C3), and P3. A reference electrode was placed at the left earlobe (A1). The electrode impedance was kept below 5 kΩ at all recording sites. The electrooculogram (EOG) was recorded from the right suborbital region. Trials with EOG waveform exceeding 80 μV were rejected (Akaiwa et al., 2022a). EEG signals were recorded with a 0.1–200 Hz band-pass filter at a sampling rate of 1,000 Hz. The SEP analysis window was from 50 ms before to 100 ms after the stimulus onset. The amplitude of four SEP components were calculated by peak-to-peak methods.