What resolves this contention: Whether feedforward vs feedback corticocortical…

What resolves this contention: Whether feedforward vs feedback corticocortical inputs follow the canonical 'FF→middle layers, FB→L1/deep' rule. The first paper supports a clean cell-type and laminar selectivity (FF/FB both prefer 'looped' projection-class targets in L5/L6), while the second finds that long-range inputs onto L5 thick-tufted pyramidal cells violate the canonical layer-based rule at the dendritic-domain level. / FF and FB afferents showed similar cell-type selectivity, making stronger connections with looped neurons than with other projection types in layer (L)5 and L6, but not in L2/3, resulting in selective modulation of activity in looped neurons. / We show that input pathways target distinct dendritic domains with far greater specificity than appears from their axonal branching, often deviating substantially from the canonical patterns.