Fig. 5. DCMD responses to 30 consecutive approaches of a `locust' or `bird' at 34 s intervals. (A) Sample raster plots from one sequence of 30 approaches showing responses of the right DCMD to a `locust' (black) and a `bird' (red) approaching from +45° azimuth. (Bi) The peak spike rate, (Bii) the spike rate at t=–200 ms and (Biii) number of spikes decreased following the first approach of either a `locust' (black circles and line) or `bird' (red circles and line) and plateaued after 10 or 15 approaches. Data plotted (means ± S.D.) are from 9 animals. For clarity the S.D. is shown in only one direction. Mean values of each plot were well fit by a single exponential decay of the form y=y₀+ae^-bx. r² values for each plot are indicated. Means were calculated from pooled right and left DCMDs (0° azimuth trajectories) and pooled ipsilateral DCMDs (±45° azimuth).