Fig. 4. (A) Distribution of differences in preferred directions (on x axis in units of radians) within each pair of selected patches. For the majority of tests there was no difference in preferred direction (PrefDir.) between the two patches (peak at zero). (B) The response range of each patch is plotted against the response range of the other patch in the pair (the largest response range was plotted on the x axis for all tests). Response range was defined as the difference between the largest and the smallest responses on the directional tuning curve. Values are means ±1 s.e.m.; for N values, see Materials and methods.