Fig. 4

Impacts of electrode spacing. (A) Illustrations of electrode configurations with vessel maps (top line) and corresponding subtracted changing areas calculated from stimulations with different electrode spacings (bottom line). A: anterior; L: lateral. (B) Super pixel time courses of the two conditions. The solid lines were obtained from the red dots nearest to source electrodes indicated in (A) and the hollow ones (labeled “distant”) were obtained from the far-most dots in (A). (C) Maximum reflectance changes among all rats imaged. The two different electrode spacing conditions showed significant differences. *: p < 0.01. (D) Calculated changing area ratios of the two conditions. The pixels of the areas having more than 3‰, 5‰, 7‰ reflectance changes were counted, and the ratios were then calculated to the maximum value (3‰ at 600 μm electrode distance), respectively