Shows the decomposition of a flow field into responses of divergence, curl, and shear.

The meaning of symbols is: “/” response depends linear on the declination x that is the distance to the center of the visual field measured along the x-axis; “−” constant response independent of x; “∩” response with hyperbolic dependence on x, a discontinuity is attained if fixating the edge tangentially; “0″ no response. The cortical transform changes the different response characteristics; however, for all three sensors the tilted plane does not result in a hyperbolic response curve. Thus, fixating at the center (tilted cases) is qualitatively different from fixating at the edge (parallel cases).