Figure 2
Left and right fields (L and R circles) of visual sensation and magnitude estimates as a function of electric current in mA (line-scatter charts). The top, middle, and bottom visual fields indicate threshold, mid, and upper level sensations. All stimuli were at 10 Hz. (a) Forehead and right mastoid plate electrodes. (b) Forehead plate electrode and top (Cz) cup electrode. (c) Right ear canal tiptrode and right temple plate electrode. (d) Right ear canal tiptrode and left mastoid plate electrode.
