Larger dendrite opportunity identified 103 of 134 one-way connection directions in one selected MICrONS sample

We tested a fixed anatomy rule for connection direction in the MICrONS release-v1 edge table. Both cells needed positive measured opportunity toward the other cell, and exactly one direction needed a detected synapse. The sample had 134 pairs and 101 cells from one mouse. Selecting the direction with the larger dendrite opportunity value identified 103 directions, or 76.9 percent. A nominal 95 percent cell bootstrap interval was 64.8 to 88.2 percent. Accuracy stayed between 75.8 and 78.5 percent when each cell was omitted. A same-area-group and layer check identified 54 of 68 directions. Three released response similarity measures were equal in the two directions for all selected pairs. Shared symmetric terms cancel in a conditional direction model under stated Bernoulli assumptions. The result gives a simple anatomy baseline, not a causal effect or a rule across mice. Selected cells, final-circuit geometry, reconstruction errors, unmeasured cell traits and nominal bootstrap coverage limit inference. The package contains new code, aggregate evidence, a figure, source hashes and retrieval steps. External records stay outside the bundle.

MICrONS · connection direction · axon-dendrite proximity · connectomics · prediction baseline · symmetric similarity