Non-invasive recording of EEG from the cervical spinal cord via surface electrodes placed around the neck

Data and scripts used for Chander et al. 2022. EEG data recorded via 10 electrodes placed around the neck of 17 healthy young human individuals, in addition to EEG data recorded from scalp electrodes (numbers of electrodes vary across individuals), an ECG channel, and EOG channels. The reference electrode was placed above the right acromion, the ground electrode above the left acromion. Sampling rate 5000 Hz, online lowpass filter 1000 Hz, online highpass filter .1 Hz (BrainAmp DC amplifier). During recordings, the left median nerve of participants was stimulated using a DS7 Digitimer at ~110% of motor threshold (constant current stimulation, 50-500 µsec pulse width (depending on the participant), square wave) at 3 Hz. 15% of stimuli were pseudo-randomly omitted. Participants counted the number of omissions in each of 3 minute blocks. The montage for neck electrodes is explained in Chander et al. 2022. There are three trigger values: 1 = experimenter pressed a key to start the experiment, or to initiate a new block. 130 = median nerve stimulation. 99 = omission. Further details in Chander et al. 2022. The scripts are mostly aiming at characterizing high-frequency signals (400-1200 Hz) in response to median nerve stimulation (8 to 16 ms), and their dissociation from the evoked response.