p364fig10.13 The bottom-up adaptive filter, intracortical grouping circuit, and intercortical top-down attentional circuit all use the same competitive decision circuit between layers 6 and 4, called the attention-preattention interface, with which to select the featural patterns that will be processed.<BR>||  Bottom-up filters and intracortical grouping feedback use the same 6-to-4 decision circuit, LGN-> Vx[6,4,2/3].  competitive decision circuit, modulatory on-center off-surround network.  Top-down intercortical attention also uses the same 6-to-4 decision circuit!