Brain recorder software

Participants were sat at about 60 centimetres from the screen (HP L1710 17-inch LCD Monitor; frame rate of 60 Hz), and the EEG was recorded using a Brain Products Package.
The individuals scalp was first cleaned using abrasive gel and then the actiCAP cap was placed on their heads. The data was recorded from 16 Ag/AgCl active electrodes (Brain Products), placed in Fp1, F3, Fz, F4, FCz, C3, Cz, C4, T4, P7, P3, Pz, P4, P8, O1, and O2 locations according to the international 10–20 standard system. The ground electrode was placed at AFz position and the reference electrode at T3 position. Their impedance was kept under 10 kΩ. The electrodes were connected directly to the 16 channels Brain Products V-Amp Amplifier and sampled at 1000 Hz. EEG data was recorded using the Brain Products Brain Recorder software with notch filter at 50 Hz, while the stimuli were presented to the subjects. For each paradigm the individuals were informed about the respective tasks. Each experimental procedure (preparation + 5 paradigms) took around 70 minutes to complete.

EEG data were recorded using a 32-channel MR-compatible EEG system (Brain Products GmbH, Gilching, Germany). The EEG cap (BrainCap MR, Brain Products) consisted of 31 scalp electrodes placed according to the international 10–20 system electrode placement and one additional electrode dedicated to the ECG which was placed on the back of the subject. Data were recorded relative to an FCz reference and a ground electrode (GND) according to 10–20 electrode system. Data was sampled at 5000 Hz to enable removal of MRI gradient artifact. The impedance between electrode and scalp was kept below 5 kΩ. EEG was recorded using the Brain Recorder software (Version 1.03, Brain Products). To prevent the movement of the subjects’ head, we placed sufficient padding between the head and the head coil of the MRI scanner. Total time for each rest EEG recoding was same as rsfMRI recording (9.24 min), and time locked to each other.