Paths with receptor signs gave no clear added calcium prediction gain in a fixed test across 103 C. elegans worms

We tested whether paths with signs from transmitter and receptor genes help predict calcium changes after neuron stimulation. We used 52,147 changes from 1,228 events in 103 C. elegans worms. All 302 neuron slots in the corrected Cook map could act as relays. The expression rule reproduced all 3,638 original published labels. It assigned unique signs to 48.7% of Cook chemical edges and 57.6% of chemical weight. The control included unsigned paths, sign coverage, transmitter signs, cell identity and measured source activity. Five outer folds excluded whole test animals. Inner animal folds selected ridge penalties. Adding direct and two-step receptor path scores increased mean squared error from 0.486128 to 0.486462, or 0.069%. A descriptive 95% range from 199 animal-weight refits was an error reduction of -0.308% to +0.057%. The unsigned path and coverage block reduced error by 1.10%. Planned sample and response-window checks gave no clear receptor gain. The complete raw-data rebuild matched the response table. The package has code, inputs, provenance, model states, predictions, figures and repeat steps. These conditional response estimates use observed source activity. The result limits the specified scores and estimator. It does not test an isolated synapse sign or show that signs have no biological effect.

connectome · Caenorhabditis elegans · structure and function · synaptic sign · receptor expression · calcium imaging · signal propagation · animal validation · signed paths