What resolves this contention: Whether anatomical/developmental microcolumnar g…

What resolves this contention: Whether anatomical/developmental microcolumnar grouping predicts excitatory connectivity in mouse cortex: sister-clone L4 pairs are preferentially wired, but apical-bundle co-membership does not predict L5B pyramidal connectivity. / Clonal sister-cell L4 excitatory neurons in mouse barrel cortex form reciprocal E→E connections at significantly higher rates than non-clonal pairs at <50 μm intersomatic distance. / Paired recordings of L5B pyramidal neurons in mouse S1 show that connection probability does not depend on whether the pair share an apical-dendrite bundle (a microcolumn-like anatomical grouping).