Fig. 5: Temporal spiking patterns depend on scanning speed.

A Responses of three example neurons to two different textures (City Lights, a fabric with fine textural features and coarse ridges, as well as a dot pattern). Colors denote scanning speed, with darker colors corresponding to faster speeds. On the left, spikes are plotted across time. On the right, spikes times are “warped” such that each spike is plotted per mm of the texture rather than ms in time (by multiplying inter-spike intervals by scanning speed). B Timing-based classification of texture when trained on responses to textures presented at one speed (60, 80, 100, or 120 mm/s, n = 49 cells) and tested either within speed (cyan) or across speeds (dark blue). On the right, spike times are warped as in (A), and classifiers are trained and tested on these warped spike trains. Chance performance is 10% (dashed line). C Mean classification based on timing (blue) or rate (red), within and across speeds. Two cross-speed classifiers were assessed; light bars represent unwarped (spikes/ms), dark bars represent warped (spikes/mm) spike trains. Boxes show the median and interquartile range and the whiskers show the full range across 49 neurons and speed combinations (within speed, n = 4 speeds; across speeds, n = 12 combinations). D Mean cross-speed population classification based on rate (unwarped, red), timing (warped, blue), and an averaged combination of both (purple). Shaded regions denote standard deviation across 1000 iterations of randomly sampled populations of neurons.