p375fig11.06 The contrast constraint on binocular fusion is realized by obligate cells in layer 3B of cortical area V1.<BR>||  Model implements contrast constraint on binocular fusion (cf. "obligate" cells Poggio 1991).  An ecological constraint on cortical development.  [left, right] eye cart V1-[4 monocular simple, 3B binocular simple, complex2/3A] cells.  Inhibitory cells (red) ensure that fusion occurs when contrasts in left and right eye are approximately equal.