Synapse spacing had correlation 0.239 in two adult C. elegans maps after count, cell-class and geometry summary controls

We tested whether synapse spacing agrees between adult C. elegans maps after count and anatomical controls. We used 6,815 released connection records from Balshayi and colleagues. The main panel had 863 common directed connections in Witvliet adult maps 7 and 8. The score was the log ratio of actual mean synapse distance to the mean for random proximal locations. We adjusted both map scores for the count, proximal-point count and random mean distance in each map, their squared terms, and source and target cell classes. Residual correlation was 0.239, with an approximate 95% cell-class deletion interval of 0.065 to 0.398. Two comparisons with adult N2U gave 0.202 and 0.241. The main correlation was 0.221 without muscle targets and 0.260 when counts differed between maps. An added audit found dependent random controls when named connections had equal counts. Source code reuses their random seed. The main residual result kept its direction after excluding these records. We also checked that the log random-distance denominator cancels from the adjusted outcome. This is modest agreement of relative spacing in three fixed maps. It does not show common cluster positions, neural function or a population effect. The package preserves code, source-derived records, provenance, figures, controls and repeat instructions.

Caenorhabditis elegans · connectome · synapse spacing · synapse clustering · cross-animal comparison · random seeds · conditional correlation · reproducible research