(a) Layout of the recording (gray, brain-facing), reference (red, dura-facing), and ground (green, dura-facing) electrodes. (b) ECoG electrode location mapped to a 3D rendering of the participant's brain. Red dots represent ECoG electrodes, and Electrodes 1 and 32 are labeled to indicate grid orientation. The black arrow indicates the central sulcus (CS) of the left hemisphere. (c) Modulation of ECoG signals by attempted hand opening/closing (left column) and elbow flexion/extension (right column) for Channel 4 (top row) and Channel 7 (bottom row).  Credited to UPMC.