p161fig04.37 Kanizsa squares that form either collinearly to their inducers (left panel) or perpendicular to them (right panel) confirm predictions of the BCS boundary completion model.<BR>|| Analog-sensitive boundary completion.  contour strength vs Kanizsa square image.  Increases with "support ratio" (Shipley, Kellman 1992). Inverted-U (Lesher, Mingoloa 1993; cf Soriano, Spillmann, Bach 1994)(shifted gratings). p370h0.6 BCS = Boundary Contour System, FCS = Feature Contour System. p161c1h0.85 "... As predicted by the BCS, they found an Inverted-U in contour strength as a function of line density. ... This effect may be explained by the action of the short-range competition that occurs <I>before</i> the stage of long-range cooperative grouping by bipole cells (<A HREF="http://www.BillHowell.ca/ProjMini/TrNNs_ART/images- Grossberg 2021/p153fig04.32 Double filter and grouping network.png">Figure 4.32</a>). It is thus another example of the balance between cooperative and competitive mechanisms. ..."