Population statistics of EIT images. A) and B) Grand average normalized conductivity change (δσ) at 8 ms for stimulation of whisker group 1 (δ, γ, E1, and D1), and group 2 (D2, C2, D3 and C3) respectively (n = 16 in 4 rats). C) and D) Significance map of peak δσ across rats and trials, projected onto the pial surface, across all layers (n = 16 in 4 rats) for group 1 and group 2 respectively.