Figure 8. Distributions of minimum detectable modulation depths and differences obtained with spike train classification techniques indicate that spike timing information is crucial for many cells. a, c, e, Left histograms indicate the lowest modulation depth that could be reliably (72.5% corresponds to a p value of < 0.001) discriminated from the unmodulated control tone. b, d, f, Right histograms indicate the smallest difference in modulation depth (e.g., for 10%, 10 vs 20%, or 50 vs 60%) that could be reliably discriminated by the classifiers. The classifier type is indicated above each panel. White bars indicate that the result was obtained at the lowest modulation depth (a, c, e) or modulation depth difference (b, d, f) presented to the cell, allowing for the possibility that the actual threshold is lower. Black bars indicate that the threshold value obtained was not the lowest tested modulation depth.