Fig. 4

Technical validations. (a–c) A high-resolution MRI-derived finite element method (FEM) model computed for frontal, motor, and parietal stimulation montages. These quasi-static models are generalizable to 0, 5, and 30 Hz. (d–f) FEM model-predicted voltage topography (Model) during stimulation compared with single-participant (participant 10) peak scalp voltage (EEG) for frontal, motor, and parietal stimulation. (g) Baseline corrected EEG Welch power spectral density (PSD) computed over 30-sec periods pre, during, and post stimulation for participant 10 over all 9 stimulation conditions. (h) Percent change in deviation for behavioral (CTT) results for Experiment 1 averaged across 4 trials of each indicated stimulation condition. Data are summarized across participants and stimulation montages. Blacked out boxes indicate missing data. (i) Percent change in deviation for behavioral (CTT) results for Experiment 2 averaged across 20 trials of each indicated stimulation montage. Data are summarized across participants and stimulation montages. (j) Percent change in deviation for Experiment 2 across participants on a trial level for each of the 20 stimulation trials. Colorbars indicate the minimum (red), maximum (blue), and no change (white) in mean CTT deviation during 30 sec of stimulation compared to 30 secs before stimulation. For panels (i) and (j) repeated participants are indicated with individual colors and linked gray bars. Exemplary timeseries trials (trial 1) for an (k) F30 and (n) M30 session. Timeseries indicates combined EEG (channel C3), ECG, and CTT data (raw and moving average) before, during, and after stimulation; with an expanded view (inset) of EEG and ECG data. Spectrogram for an (l) F30 stimulation trial, derived from the EEG timeseries trial in panel (k) and spectrogram for an (o) M30 stimulation trial, derived from the EEG timeseries trial in panel (n). One trial of behavioral (CTT) data, for an (m) F30 and (p) M30 stimulation trial, comparing 30 secs before (Pre), during, and after (Post) stimulation. Mean deviation is indicated by dashed vertical lines. Panels (k–p) all show exemplary data for participant 24. (q,r) Behavioral (CTT) deviation from the center of the annulus, for one participant who repeated Experiment 2, three times with F30 and M30 montages. Each experimental run is indicated with a different participant number (1st run = 22, 2nd run = 23, 3rd run = 24). Deviation scores are indicted for 30 secs pre, during, and post stimulation. Mean deviation is indicated in orange, median is indicated in yellow, and each trial is indicted in shades of blue.