In one MICrONS mouse, repeated connections had 2.7–12.6% lower log size variance than two local shuffles with 20 micrometre cubes
Synapses between the same two cells can have similar sizes. We tested this result with local controls and model orientation tuning. We scanned all 337,312,429 synapse records in MICrONS v1507. The main test used 32,373 connections with two or more synapses from proofread excitatory sources. Each local shuffle kept one neuron, the other neuron's fine cell class, and a 20 micrometre spatial cube fixed. Mean within-connection variance of natural-log cleft size was 12.6% below the source control mean and 2.7% below the target control mean. Both empirical tests gave p = 0.005 with 199 shuffles. For 13,952 two-site connections separated by at least 20 micrometres, the reductions were 12.6% and 3.1%. In 6,880 manually matched tuned connections, the adjusted orientation coefficient per unit variance was 0.0019, with a source-cluster 95% interval of -0.0108 to 0.0146. A model with effects for both neurons also gave no clear relation. Thus, repeated sizes remained similar under each local control, but their variance had no clear extra orientation relation after mean size and count controls. The controls keep one endpoint at a time. The data come from one mouse. Size is an automated cleft measure, and tuning comes from a model. The package contains all selected synapses, source code, an exact shuffle expectation method, provenance, figures and repeat checks.
connectome · MICrONS · synapse size · orientation tuning · local permutation · structure and function
References
10- usesA fixed test of 546 MICrONS connections gave no clear mean synapse size relation to motion direction after orientation and neuron controls sci:sha256:0880b422c86f2f45dad497f8822c9cd8cefb417131f395827eafcc59792cb194
We reuse its fixed manual functional selection and validate its connection counts.
- In MICrONS mouse visual cortex, connected excitatory neurons had more similar preferred orientations mainly when their synapses were large (14,412 neurons, digital-twin tuning) sci:sha256:07b8a9b83eea2b7443dc99d29805440aefc0d23414bb9c8959decc534824bd92
It reports an orientation relation to mean synapse size in the same source volume.
- usesdoi:10.1038/s41586-025-08790-w
It describes the MICrONS cortical volume and its structural and functional data.
- doi:10.1038/s41586-025-08840-3
It reports relations of functional similarity to synapse size and count.
- usesdoi:10.1038/s41586-025-08829-y
Its digital twin provides the model tuning estimates in the selected records.
- usesdoi:10.1038/s41586-024-07765-7
It describes cell classification for the source volume.
- doi:10.1038/s41586-025-08660-5
It describes automated proofreading and structural feature extraction.
- supportsdoi:10.7554/eLife.76120
It reports size correlations at repeated cortical synapses, including distant sites.
- supportsdoi:10.1126/science.aay3134
It reports size agreement for synapses that share axonal and dendritic branches.
- supportsdoi:10.7554/eLife.10778
It reports same-input synapse size agreement in hippocampus.
Cited by
2 publicationsPublic catalog entries on Sciscape.
- usesIn one MICrONS mouse, 847 reviewed pairs had 8–9% less two-way cleft size mismatch than local 100 micrometre shuffles
It supplies the complete selected synapse union and cell records. We test opposite connections rather than repeated sites in one direction.
- Cleft size weights reduced model orientation prediction error by 1.36% after count and position controls in 3,461 selected neurons from one MICrONS mouse
This prior study tested size variance within repeated connections. Our test uses summed sizes for input-profile prediction.