Similarity between neuronal encoding of pairs of neurons within and between nuclei. (A-C) Mean Victor-Purpura distance between pairs of spike trains from different neurons with the same baseline firing rate, during injection of similar currents. The comparison is between the distances of pairs within the same nucleus to distances of pairs in different nuclei. (A) Red: GP-GP pairs (±SEM, n = 89, p < 0.001, Wilcoxon rank sum test), blue: GP-EP pairs (n = 73, p < 0.001), green: GP-SNr pairs (n = 119, p < 0.001). (B) Red: EP-GP pairs (±SEM, n = 73, N.S., Wilcoxon rank sum test), blue: EP-EP pairs (n = 24), green: EP-SNr pairs (n = 47, N.S.). (C) red: SNr-GP pairs (±SEM, n = 119, N.S., Wilcoxon rank sum test), blue: SNr-EP pairs (n = 47, p < 0.00), green: SNr-SNr pairs (n = 43, p < 0.001).