Braincap

Electromyography data were acquired using an MRI-compatible Brain Products’ BrainCap consisting of 2 bipolar and one reference electrode. The electrodes with a diameter of 2 mm were filled with electrode paste and positioned in pairs over the CS and LL on the left side of the face (Cacioppo et al., 1986 (link); Fridlund and Cacioppo, 1986 (link)). A reference electrode, 6 mm in diameter, was filled with electrode paste and attached to the forehead. Before the electrodes were attached, the skin was cleaned with alcohol. This procedure was repeated until electrode impedance was reduced to 5 kΩ or less. The digitized EMG signals were recorded using a BrainAmp MR plus ExG amplifier and BrainVision Recorder. The signal was low-pass filtered at 250 Hz during acquisition. Finally, data were digitized using a sampling rate of 5 kHz, and stored on a computer running MS Windows 7 for offline analysis.

Spontaneous EEG was recorded with a TMS-compatible 64-channel EEG cap (BrainCap, BrainProducts, Germany; Ag/AgCl electrodes) in accordance with the 10–10 extended international system. All electrodes were referred to the right mastoid and impedance was kept below 5 kΩ using a viscous electrode paste (Abralyt HiCl Gel, EasyCap, Germany); the ground electrode was incorporated in the cap at AFz. BrainRecorder software and BrainAmp MR Plus amplifiers (BrainProducts, Germany) with a 5000 Hz sampling rate and low-pass filter of 1000 Hz (no high-pass filter, resulting in a DC recording) were used to record periods of EEG throughout the experiment. Participants were at rest, with eyes open and gaze steadied on a fixation point.

All patients' brain activities were measured by EEG in a sitting position with eyes opened before, during, and after EA treatment. A 32-channel EEG based on the international 10–20 system was placed on the patients' scalp and recorded in a quiet room using BrainCap (Brain Products, Gilching, Germany) with a sampling rate of 1000 Hz. The ground electrode and reference electrode were placed in front and behind the Fz electrode, respectively. The electrode impedances were set to <5 kΩ. The brain wave data were continuously recorded for 30 minutes, including the 5-minute baseline EEG recording before EA treatment, the 20-minute EEG recording during the EA period, and the 5-minute EEG recording after removal of needles.

EEG was recorded in a quiet room. Participants were instructed to close their eyes and stay awake. Recordings lasted for 2–3 min. We used a BrainCap with a 10–20 system and a BrainAmp (Brain Products GmbH, Germany) 16-bit ADC amplifier. The sampling rate was 500 Hz. Of the 32 recorded channels, one was used to monitor the lower vertical electrooculogram and one was used to measure electrocardiographic activity. Two were positioned at the earlobes for re-referencing purposes to remove the bias of the original reference, which was placed at FCz. Data analysis was conducted for data collected from the remaining 27 electrodes F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T7, T8, P7, P8, Fz, Cz, Pz, FC1, FC2, CP1, CP2, FC5, FC6, CP5, CP6, TP9, and TP10. Impedances were kept below 10 kΩ.
The two EEG sessions were arranged to take place at the same time of the day. For most participants, this requirement was met by performing EEG within the same time-range around noon, after lunch (1 pm.). This means that we aimed to keep the time difference between the two recordings below 3 h. For three participants (HC, SCC, TLEl) the time difference was approximately 4 h, for two patients (MCI, TLEr) the time difference was 6 h, and for one HC the time difference was 11 h.
Table S4 lists the results of a clinical evaluation of the EEGs of all participants included in this study.

During the experiments, EEG signals were sampled at 1000 Hz using a multi-channel EEG acquisition system (BrainCap, Brain Products, Munich, Germany) with 63 scalp electrodes placed according to the international 10–10 system. The electrode locations were Fp1–2, AF3–4, 7–8, Fz, F1–10, FT7–8, FCz, FC1–6, T7–8, Cz, C1–6, TP7–8, CPz, CP1–6, Pz, P1–10, POz, PO3–4, 7–8 and Oz, O1–2. Two EOG channels were created by bipolarly referencing two pairs of electrodes (horizontal EOG channel: F9–F10; vertical EOG channel: (Fp1+Fp2)/2). The EEG signals were referenced to the left mastoid with a forehead ground. The hardware bandpass filter with cutoff frequencies of 0.016 and 250 Hz was applied before the sampling. The impedance of all electrodes was kept below 20 kΩ.

EEG was recorded in a quiet room using a BrainCap with a 10–20 system and a BrainAmp (Brain Products GmbH, Germany) 16-bit analog-to-digital converting amplifier. The sampling rate was 500 Hz. Of the 32 recorded channels, one was used to monitor the lower vertical electrooculogram and one was used to measure electrocardiographic activity. Two channels were positioned at the earlobes for rereferencing purposes to remove the bias of the original reference, which was placed at FCz. Data analysis was conducted for a subset of 17 electrodes: F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T7, T8, P7, P8, Fz, Cz, and Pz. Impedances were kept below 10 kΩ.
The two EEG sessions were arranged to take place at the same time of the day. For most participants, EEG was performed within the same time range around noon (1 pm).

The electroencephalogram (EEG) was recorded at a sampling rate of 500 Hz from a 31 channel ActiChamp amplifier and a 31 active electrode Braincap (Brain Products GmbH, Gilching, Germany). The electrodes were placed according to the extended 10–20 system: Fp1, Fp2, F7, F3, Fz, F4, F8, FC5, FC1, FC2, FC6, T7, C3, Cz, C4, T8, CP5, CP1, CP2, CP6, P7, P3, Pz, P4, P8, Oz, and at the left (M1) and right (M2) mastoids. Three electrodes recording the horizontal and vertical electrooculogram (EOG) were positioned to the left and right of the outer canthi of the eyes and below the left eye. The reference electrode was placed at the tip of the nose.
The pupil diameter of both eyes was recorded with an infrared EyeLink Portable Duo eye-tracker (SR Research Ltd., Mississauga, Ontario, Canada). The eye tracking was set up in remote mode at a sampling rate of 500 Hz.