Thesis
General anesthesia is a network-level state transition driven by coordinated partial perturbation at conserved targets (SNARE release, Complex I, K2P channels, nAChR, NCA leak, GABA-A potentiation), not a single-target binding event. Mutants in any one target give partial phenotypes; non-immobilizers like hexafluoroethane fail despite engaging some of the same targets. Specificity emerges from the integrated network response, not the molecular fit.
The validator operationalises this directly. Per-anesthetic Hill-curve perturbation profiles are built from primary literature EC50/IC50 measurements, applied to the Cook 2019 C. elegans hermaphrodite connectome via a 300-neuron Brian2 LIF brain, and read out as quiescent-state enrichment in the locomotion command-interneuron set.
Interactive: V3 ensemble explorer
Five tabs over the V3 worm ensemble + V4 fly cross-species ensemble. Pick a volatile to see its Hill-shaped dose-response against the published worm EC50; toggle a mutant to see the Hill curve shift left (hypersensitive) or right (resistant); compare the three Eger compounds side-by-side to see why the conserved-substrate model distinguishes anesthetics from non-immobilizers; open the perturbation profile to see which mechanism classes each compound engages with primary literature anchors; or open the Cross-Species tab to compare the same architecture’s predictions on the C. elegans (Cook 2019, 300 neurons) and Drosophila larva (Winding 2023, 2,952 neurons) connectomes side-by-side.
Architecture
literature-grounded perturbation table ──▶ 300-neuron Brian2 LIF brain ──▶ network-state metrics
(per-(anesthetic, target_class) (Cook 2019 connectome, • quiescent fraction
EC50, max effect, Hill n, Loer & Rand 2022 NT identity, • command-interneuron mean rate
primary-PMID-anchored) per-edge CeNGEN Glu sign overlay) • population state autocorrelation
- Perturbation profiles for 9 compounds × 8 mechanism classes built from Mihic 1997, Patel & Honoré 1999, Forman 1996, Stewart 2000, Hanley 2002, Lu 2007, Belelli 1997, plus Eger 2001 for non-immobilizers. Each row carries a primary PMID; missing (anesthetic, class) cells are explicit
DEFERRED(not imputed). - Mutant baseline shifts (Complex I rate factor for gas-1, gas-2, nduf-6, ndus-8, nuo-1 per Kayser 2001; NCA leak factor for unc-79, unc-80 per Sedensky 1992; synaptic weight scaling for Gαo loss-of-function in goa-1, dgk-1 per Lackner 1999, Nurrish 1999).
- One free calibration parameter (α = 0.13), tuned only against halothane WT (Crowder 1996, EC50 = 340 µM aqueous). All downstream gates use the same locked α.
- Ensemble protocol: 60 s simulation × 5 seeds per (anesthetic, dose, genotype). 545 sims total; 8-core parallel; 23 min wall on RTX 4060 Ti host.
Validation gates
| Gate | Test | Predicted | Published | Error / score |
|---|---|---|---|---|
| 1 | Halothane WT calibration | 317 µM | 340 µM | 1.07× |
| 2 | Isoflurane WT — held out, no re-tuning | 291 µM | 290 µM | 1.002× (essentially exact) |
| 3 | Mutant directional accuracy (n=9) | — | — | 9 / 9 correct (100%) |
| 4 | Eger non-immobilizer specificity (n=3) | — | — | 3 / 3 correct |
Calibration uses one anchor and one parameter. Held-out tests then run with no further tuning.
Mutant directional accuracy — Gate 3 detail
| Gene | Direction (WB ontology) | Pred. EC50 | Mutant / WT ratio | Lit. ratio | In band |
|---|---|---|---|---|---|
| gas-1 | hypersensitive | 221 µM | 0.70 | 0.33–0.5 | close (within 1.5× of upper) |
| gas-2 | hypersensitive | 252 µM | 0.80 | 0.5–0.7 | close |
| nduf-6 | hypersensitive | 238 µM | 0.75 | 0.4–0.6 | close |
| ndus-8 | hypersensitive | 238 µM | 0.75 | 0.4–0.6 | close |
| nuo-1 | hypersensitive | 238 µM | 0.75 | 0.4–0.7 | in band |
| unc-79 | hypersensitive | 226 µM | 0.71 | 0.33–0.5 | close |
| unc-80 | hypersensitive | 226 µM | 0.71 | 0.33–0.5 | close |
| goa-1 | resistant | 860 µM | 2.72 | 1.5–3.0 | in band |
| dgk-1 | resistant | 620 µM | 1.96 | 1.5–2.0 | in band |
WBPhenotype anchors: WBPhenotype:0001611 (halothane hypersensitive), WBPhenotype:0001618 (halothane resistant). Citation paths preserved per gene. The two RESISTANT predictions land squarely in their published literature ranges; the seven HYPER predictions are all directionally correct with magnitudes slightly less extreme than published (within 1.5× of upper bound).
Eger non-immobilizer specificity — Gate 4 detail
The Eger 2001 panel was designed to falsify lipophilic-pocket-fit theories of anesthesia: hexafluoroethane and trans-1,2-dichloroethylene have appropriate lipid solubility for Meyer-Overton anesthetics but produce no immobilization in mammals. Cis-1,2-dichloroethylene, the stereoisomer, is an anesthetic. Single-pose docking pipelines cannot distinguish them. The network-state validator can:
| Compound | Eger 2001 class | Max quiescent fraction (any dose ≤ 30 mM) | Verdict |
|---|---|---|---|
| cis-1,2-DCE | anesthetic | 0.988 | correct |
| trans-1,2-DCE | non-immobilizer | 0.000 | correct |
| hexafluoroethane | non-immobilizer | 0.000 | correct |
Same architecture, same α, no compound-specific tuning. The non-immobilizers’ command-interneuron firing rates do drop monotonically with dose (any partial K2P engagement contributes), but neither crosses the immobilization threshold across four orders of magnitude (30 µM → 30 mM).
What this replaces
An earlier project iteration built a binding-occupancy → kinetic-shift → network → behavior chain driven by AutoDock Vina docking against AlphaFold structures of 30 C. elegans anesthetic targets. That pipeline failed three diagnostic tests:
- Vina ΔG was dominated by ligand chemistry: per-target regression of
log(predicted Kd)on(clogP, MW)across 14 ligands gave median R² = 0.735 — the docking step contributed ~7 percentage points of pooled variance over chemistry alone. - Predicted Kd was anti-correlated with worm-behavioral EC50 on the clean primary-anchor subset (Pearson r = -0.84, n=4, wrong sign).
- Anesthetic vs Eger non-immobilizer discrimination was 91% chemistry: regressing out (clogP, MW) collapsed Cohen’s d from -1.18 to -0.11 (Mann-Whitney p went from < 0.0001 to 0.50). Meyer-Overton beat the pipeline as a worm-potency predictor.
The diagnostic work also surfaced architectural failures downstream: a max()-aggregation in the perturbation manager collapsed 5 of 6 anesthetics to within 4 pA of each other at 1× EC50 despite EC50s spanning four orders of magnitude, and the Phase F gas-1 prediction was structurally invariant to the anesthetic-specific input (the block_factor term cancels analytically in the d_WT / d_g1 ratio).
The network-state validator above replaces that chain entirely: literature EC50s instead of Vina-derived occupancies, the full 300-neuron Cook connectome instead of a 50-neuron LIF demo, and direct network-state metrics instead of max()-aggregation followed by classifier-bank pattern matching. Calibration uses one anchor and one parameter; everything else is held-out.
Three-organism validation (V4 + V6) on a substrate-agnostic LIF integrator
The architecture transfers to Drosophila larva (Winding 2023 connectome, 2,952 neurons) and Mus musculus (generic LIF random graph, 3,000 neurons — no mammalian connectome required per V5 M2). Three independent organisms, three single-anchor calibrations.
| Gate | worm V3 (Cook 2019) | fly V4 (Winding 2023) | mouse V6 (random graph) |
|---|---|---|---|
| 1 — halothane WT calibration anchor | 317 µM (1.07× off 340) | 361 µM (1.06× off 340) | 297 µM (1.18× off 350) |
| 2 — held-out volatile (isoflurane) | 291 µM (1.002× off 290) | 323 µM (1.11× off 290) | 273 µM (1.06× off 290) |
| 3 — mutant magnitude predictions | inside lit band: 4/9 | inside lit band: 5/13 | inside lit band: 4/10 |
| 4 — Eger non-immobilizer specificity | 3 / 3 | 3 / 3 | 3 / 3 |
| α (free parameter, single-anchor) | 0.13 | 0.060 | 0.10 |
What survived adversarial controls — V5 + V5+ findings
V5 M2 (connectome permutation) and V5+ (no-integration sign-only baseline + Meyer-Overton baseline) jointly narrow what’s actually load-bearing in the architecture:
The substrate is largely interchangeable. V5 M2: fly result transfers to fully randomized graphs (P1, P2, P3 all pass Gate 1 at frozen α). Mouse V6 uses a generic random graph by design. Worm V3 needs at minimum cell-type-aggregate connectivity (P3 passes; P1, P2 fail). The “cross-phylum” framing was over-claiming organism-specific structural recovery.
Gate 3 directional accuracy is largely sign-propagation. A no-integration sign-only baseline matches the validator on 32/35 mutants (91% — identical to the validator). Network dynamics are decorative for the direction of mutant predictions; the perturbation table’s sign convention does the work.
Cross-organism MAC similarity at ~340-350 µM is largely Meyer-Overton. A lipid:water-partition baseline calibrated on halothane predicts halothane MAC perfectly (by definition) and matches the validator at order-of-magnitude across phyla. The “striking conservation” claim collapses to “lipid biophysics conserves across cells” (Meyer-Overton 1899).
Where the architecture genuinely beats Meyer-Overton:
| test | Meyer-Overton fold-error | Validator fold-error |
|---|---|---|
| held-out isoflurane (worm + fly + mouse) | 2.89-2.97× off | 1.00-1.11× off (~3× tighter on all 3 organisms) |
| etomidate mouse | 196× off | not directly tested in V6 (mechanism-specific table addresses it) |
| ketamine mouse | 44× off | mechanism-specific |
| Eger non-immobilizers | predicts they should immobilize at high dose | correctly classifies as non-immobilizers (3/3) |
| mutant magnitude predictions | no answer (Meyer-Overton has nothing to say) | several inside literature bands (TREK1_KO 2.04 in 1.5-2.5; TASK13_dKO 2.06 in 2-3; ND-49 0.62 in 0.5-0.7; gas-1 0.57 close to 0.33-0.5) |
Honest single-line claim, post-controls
A literature-anchored conserved-target Hill perturbation table, integrated through a generic LIF substrate (no specific connectome required), recovers held-out volatile EC50s ~3× tighter than Meyer-Overton, predicts mutant magnitudes inside literature bands for several mutants in each organism, and correctly classifies Eger non-immobilizers across worm, fly, and mouse with one free parameter calibrated per organism.
The architecture is largely substrate-agnostic. The mechanism map is what does the work. Cross-organism MAC similarity is consistent with Meyer-Overton (lipid biophysics) and not strong evidence of conserved targets on its own. The architecture’s distinctive contribution is within-organism precision on held-out volatiles, mutant magnitude, and Eger discrimination — places where Meyer-Overton fails.
V6 mouse scope: LRR / immobilization phenotype only. Higher-order mammalian features (cortical EEG burst suppression, NREM-like slow oscillations, gamma suppression, consciousness disruption) are NOT in the architecture and not claimed.
Use the Cross-Species tab to compare worm + fly + mouse halothane / isoflurane curves side-by-side.
Adversarial controls (V5) — what survives, what doesn’t
Honest follow-on testing reveals where the V3/V4 result is genuinely structural and where it is over-determined:
Bootstrap 95% CIs (1000 resamples on 5-seed ensembles): predictions are precise but tight. The worm-isoflurane held-out test (predicted 291 µM, 95% CI [276, 310] µM) sits inside its CI containing the published 290 µM — the strongest of the four EC50 predictions. The other three EC50s sit just outside their 95% CIs (worm halothane CI [297, 334] vs published 340; fly halothane CI [343, 373] vs 340; fly iso CI [315, 328] vs 290). Fold-errors of 1.06–1.11× are real but not statistically consistent with published values to within seed noise.
Connectome permutation tests (Erdős-Rényi rewiring, configuration-model degree-preservation, cell-type block shuffle):
| permutation | worm Gate 1 | fly Gate 1 |
|---|---|---|
| P1 — full random rewiring | FAIL (54 µM, 6.35×) | PASS (370 µM, 1.09×) |
| P2 — degree-preserving | FAIL (168 µM, 2.02×) | PASS (380 µM, 1.12×) |
| P3 — cell-type block shuffle | PASS (319 µM, 1.07×) | PASS (356 µM, 1.05×) |
| Eger specificity (3/3) | PASS in all 6 permutations |
The “connectome-constrained” framing was over-claiming. The worm result requires at minimum cell-type-level structural connectivity (random rewiring breaks it; cell-type-block-preserving rewiring doesn’t). The fly result is NOT connectome-dependent — random graphs of comparable density also pass. The Eger specificity result is NOT a connectome claim in either organism — it’s a perturbation-table sparseness story.
The conserved-substrate hypothesis itself survives: the perturbation-table + network-integration architecture recovers behavioral phenotypes from molecular pharmacology in both organisms. What’s narrower than the original claim: the specific Cook 2019 / Winding 2023 wiring is NOT the load-bearing structural feature in either organism.
Status
- V3 worm ensemble shipped + V4 fly cross-species ensemble shipped. All four gates pass in both organisms.
- Repo:
AnestheticSimulator/(public). Built at $0 external spend on an RTX 4060 Ti. - Open work: per-mutant Complex I factor refinement (currently nduf-6 / ndus-8 / nuo-1 share an estimate; per-gene primary-literature factors would differentiate them); FlyBase driver-line NT data integration to replace V1’s cell-type heuristic; full adult Drosophila (FlyWire ~140K neurons) substrate as a follow-on.
Sources & attribution
Perturbation-table primary anchors: Mihic 1997 PMID 9311785 (GABA-A α1β2γ2 volatile EC50); Patel & Honoré 1999 PMID 10321245 (TREK-1 halothane EC50); Forman 1996 PMID 8633440 (nAChR α4β2 halothane); Hanley 2002 PMID 12411414 (Complex I IC50); Stewart 2000 PMID 11095753 + van Swinderen 1999 PMID 10051668 (SNARE Ca-cooperativity reduction; Drosophila + mammalian NMJ); Lu 2007 PMID 17972040 (NALCN block); Belelli 1997 PMID 9298537 (etomidate β-specific GABA-A); Eger 2001 Anesth Analg 92:1395 (non-immobilizer panel).
Worm-behavioral EC50 anchors: Crowder 1996 PMID 8855256 (halothane WT 340 µM); Morgan & Sedensky 1995 PMID 7549290 (isoflurane WT 290 µM, gas-1 hypersensitivity).
Mutant phenotype anchors (WB ontology): WBPhenotype:0001611 (halothane hypersensitive — gas-1, gas-2, nduf-6, ndus-8, nuo-1, unc-64, unc-79, unc-80, unc-9, cox-4, cox-5A); WBPhenotype:0001618 (halothane resistant — dgk-1, eat-16, egl-10, goa-1, ocrl-1, unc-64, cox-4, cox-5A); WBPhenotype:0001609 (isoflurane hypersensitive); WBPhenotype:0001619 (isoflurane resistant). Per-gene WBPaper IDs preserved in data/state_validation/wb_directional_mutants.csv.
Connectome substrate: Cook 2019 PMID 31270481 hermaphrodite connectome; Loer & Rand 2022 neurotransmitter identity table; per-edge CeNGEN-derived glutamate receptor sign overlay (Taylor 2021 PMID 34182862). 300 neurons (intersection of chemical synapse + NT identity rosters).
Computational stack: AutoDock Vina 1.1.2 (binding-pipeline diagnostics, deprecated for current architecture); Brian2 2.9 with cython codegen target (Stimberg 2019 PMID 31429824); MuJoCo 3.2 (body model, separate work). Python 3.11, miniconda env ml.
Author: Rohit Ravi. NYU undergraduate, Data Science with Philosophy minor. AI-assisted computational research scope; no wet-lab work performed.