Fig. 6

tDCS-induced electric field on brain areas for the study montages. tDCS-induced electric field on brain areas for the montages targeting the left dorsolateral prefrontal cortex (top line) and primary motor cortex representation of the lower limbs (bottom line). Anodal (red rectangle) and cathodal (blue rectangle) electrodes placed over the scalp (A, B, F, and G). Figures are color-coded according to the electric field strength so that hot colors (e.g., red) represent stronger electric fields and cold colors (e.g., blue) represent weaker electric fields. Frontal (C and H) and top (D and I) view of the electric current distribution in gray and white matter. Diagonal (E) and sagittal (J) view of the electric current distribution in gray matter with arrows roughly over the nominal targets (blue = left dorsolateral prefrontal cortex; red = primary motor cortex representation of the lower limbs). Note: Because the anatomical model does not include a shoulder for the M1 tDCS montage, the cathode electrode was placed on the lower part of the neck, which provides a good approximation of the should placement