What resolves this contention: Single-cell barcoding (MAPseq) shows pervasive d…

What resolves this contention: Single-cell barcoding (MAPseq) shows pervasive divergent multi-area projections from single neurons, complicating the bulk-tracer 'projection from area A to area B' interpretation that underlies the regional Allen mesoscale connectome. / MAPseq projection mapping of 591 V1 neurons shows that the dominant mode of intracortical information transfer is not 'one neuron–one target area' — most neurons project to multiple cortical and subcortical areas, often in non-random combinations. / The Allen Mouse Brain mesoscale connectome characterizes inter-areal projections at the regional/cell-type level using bulk AAV tracers averaged across animals.