64 channel eeg cap

The electroencephalogram (EEG) data were recorded using a 64-channel EEG cap according to the international 10/20 system (Brain Products, Munich, Germany), and the reference electrode was placed on the tip of the nose. The horizontal and vertical electrooculograms (EOG) were monitored via electrodes placed lateral to the external canthus of the left eye and above the right eye, respectively. The AFz electrode on the cap served as a ground. During the recordings, all electrode site impedances were maintained below 10 kΩ. The EEG data were recorded at a sampling rate of 500 Hz and amplified using a 0.016–100 Hz bandpass for offline analysis.

Participants were seated in a comfortable chair in a silent, temperature-controlled room. They wore protective goggles and were asked to focus their attention on the stimuli and relax their muscles. The EEG data were recorded using a 64-channel EEG cap with Ag-AgCl scalp electrodes placed according to the international 10–20 system (Brain Products GmbH, Munich, Germany; pass band: 0.01–100 Hz; sampling rate: 1000 Hz). The nose was used as the reference electrode, and the impedances of all electrodes were kept lower than 10 kΩ. Electrooculographic (EOG) signals were simultaneously recorded using surface electrodes to monitor ocular movements and eye blinks.

EEG experiment was carried out in a silent and temperature-controlled room. Participants were seated in a comfortable chair and wore protective goggles. The EEG data collection was performed with a 64-channel EEG cap (Brain Products GmbH, Munich, Germany). The sampling rate was 1,000 Hz and the passband was 0.01–100 Hz. The electrode impedances were kept lower than 10 kΩ. Electrooculographic (EOG) signals were simultaneously recorded using surface electrodes to monitor ocular movements and eye blinks.
EEG data were analyzed using EEGLAB (Delorme and Makeig, 2004 (link)) and in-house MATLAB scripts (MathWorks). Continuous EEG data were band-pass filtered from 1 to 30 Hz using FIR filters. EEG data were further corrected using independent component analysis (ICA) algorithm (Makeig et al., 1997 (link); Delorme and Makeig, 2004 (link); Onton et al., 2006 (link)). ICA components that were considered as purely or predominantly driven by artifacts (such as ocular artifacts, myogenic artifacts) were discarded based on visual inspection of power spectrum, time course and topography. The remaining components were re-referenced to nose.