EEG procedures
The procedures for the EEG recording in the clinical trial involved resting state EEG being recorded for 2 min for each of eyes closed and eyes open, using Curry 7, a 64-channel quick-cap system, and a SynAmps2 amplifier. In this analysis, we focused on the eyes closed recording to limit the influence of visual processing on signal variability and fluctuating attention due to wandering gaze. EEG was digitized at 1000 Hz, and impedance was kept below 10 kΩ. Data analysis and feature extraction was performed using custom Matlab scripts and routines adapted from the EEGLab toolbox [Resting state signals were filtered using independent high-pass (1 Hz) and low-pass (50 Hz) filters and resampled to 250 Hz. Line noise (60 Hz) and its harmonics (120, 180, 240 Hz) were removed using the Cleanline plugin [To reduce the number of statistical comparisons, and to focus on a generic cortical impression of complexity, the LZC and MSE were estimated first at the level of a single channel and then reduced to a single dimension by taking the mean across channels (e.g., [