Figure 10. OSDNs showed broad tuning to varying frequencies of object motion in Manduca sexta. Unit I was an exception to this pattern, showing a monotonically increasing response to the frequency test. Spiking responses to the stimulus are shown as a solid line, while baseline spike rates are represented by the dashed line. The red line through each response curve represents the regression line that was fit to the 0–2 Hz response data. The red circles indicate the raw data points the regression line was fit to. The regression analysis indicates that for the range of frequencies that M. sexta can track (0–2 Hz), response increased with frequency (coefficients for this analysis can be found in Table 2).