Graphs of the bundle cross-sectional velocity profile when Rol2 was lowered 10-fold to 20 KΩ. A: 0 gj-channels. B: 100 gj-channels. When there were 0 channels, the shape was similar to that when Rol2 was the standard 200 KΩ (see Fig. 4A). With 100 channels, there was almost no effect (compare with Fig. 4D).