A whole-organism simulator for Caenorhabditis elegans.
It simulates all 300 neurons and 95 body-wall muscles over the published electron-microscopy connectome, drives a biomechanical body through a viscous medium, and runs the animal from a fertilised egg through four larval stages to senescence and death. You can poke it anywhere on its body, knock out genes by name, laser-ablate individual neurons, and run the standard behavioural assays.
Teal is dorsal muscle, purple is ventral. The alternation running down the body is the undulatory wave that moves the animal.
git clone https://github.com/vdmkenny/celeganssim && cd celeganssim
python -m venv .venv && .venv/bin/pip install -e .
.venv/bin/python scripts/fetch_data.py # downloads ~43 MB, then builds
.venv/bin/worm serve # http://127.0.0.1:8080Requires Python 3.10+ and numpy. The viewer is standard library and vanilla
JavaScript, with no build step. Datasets are not redistributed here:
fetch_data.py pulls each from its publisher, verifies it, and builds the
processed files.
The connectome is Cook et al.'s corrected July 2020 release, published as an
Excel workbook and read by scripts/xlsx.py, a standard-library reader added
so the project keeps its numpy-only dependency. The 2019 edgelist and the
White et al. 1986 file are downloaded for comparison and are not used to build
anything.
worm serve # live browser viewer
worm validate # 52 checks against published measurements, in parallel
worm params # audit every model parameter and its provenance
worm assay all # run the standard behavioural assays
worm gene unc-25 # look up a locus
worm info # genome and connectome summary
worm export run.csv --seconds 120 --neuron AVAL
worm batch --genotype wild-type --genotype unc-25 --replicates 5Touch is a position along the body. The six touch receptor neurons tile the animal with overlapping graded receptive fields, so where you prod it determines which cells respond. Anterior touch drives reversal, posterior touch drives forward acceleration, and mid-body touch falls where the ALM and PLM fields cross over and is unreliable. These follow from the connectome rather than from rules: PLM has no chemical output at all, reaching the forward command interneuron PVC purely through gap junctions.
Mechanotransduction is phasic, as measured: the receptor current fires at stimulus onset and offset and adapts within tens of milliseconds, so the neurons report change rather than load (O'Hagan et al. 2005). Repeated plate taps habituate: synaptic depression at the touch cells' output synapses (Wicks & Rankin 1997) halves the evoked response over twelve taps and rest restores it (Rankin et al. 1990). The decrement lives in the difference of the two antagonistic tap reflexes (Wicks & Rankin 1995), which is why a localised poke habituates far less than a whole-body tap. The suprathreshold binary response does not habituate here and deeper depression sensitises it through PLM disinhibition, a wiring-level limit tracked as an expected failure.
Harsh touch (100-200 uN) is a separate channel. FLP covers the head and is
reversal-biased in the wiring; PVD tiles the rest of the body and favours
forward. Both are MEC-4 independent, so harsh responses survive in mec-4
mutants.
Left alone, the animal reverses on its own: a generator injects pulses into
the real backward command cells at the measured rates (about 2 per minute off
food, fewer on food, Gray et al. 2005; goa-1 roughly triples it, Segalat et
al. 1995). Chemotaxis is a biased random walk on top of that machinery: the
pirouette rate is multiplied down when the animal climbs a salt gradient and
up when it descends, with the measured 3x asymmetry (Pierce-Shimomura et al.
1999) and an ASE-style seconds-scale integration of dC/dt, gated by the real
ASE genome gains so che-1 and tax-4 silence it by mechanism. Honest
accounting. An earlier chemotaxis-index pass turned out to be an arena
artifact: on a small toroidal plate the scoring band covered 30% of the
surface, so a salt-blind animal scored 0.6-0.7 by wrapping through it. The
assay now uses Ward's geometry instead, an attractant spot and a control
spot with the animals released between them, where an animal that cannot
smell scores zero by symmetry rather than by the arena being the right size.
Both halves of the mechanism are now present. Klinokinesis modulates the
pirouette rate, and klinotaxis curves the forward runs: measured as the rate
at which heading error to the source falls during a run, it goes from
-0.02 deg/s with the steering off to -0.65 deg/s with it on, a clean dose
response. Together they are enough to move a plate: released midway between an
attractant and a control spot, wild type finishes on the attractant side
with an index of +0.50 while che-1, which cannot taste salt, ends up at
-0.83, the wrong side of a plate it cannot navigate.
The plate has no handedness of its own: omega turns here are always ventral,
so each animal is given a side to lie on the way a worm on agar is, and a
population averages the turn direction out. Without that, every animal curled
the same way and accumulated 371 degrees of rotation in ten minutes, which an
assay reads as behaviour. A steady gait curl remains, unrelated to
orientation, tracked as
issue #34.
The search itself has a history: dopamine carries the memory of food. In the
minutes after leaving a lawn the reversal rate runs at the local-search value,
then decays to a low dispersal rate over tens of minutes (Gray et al. 2005),
and cat-2, which cannot make dopamine, never elevates above dispersal while
its baseline stays intact (Hills et al. 2004).
A reversal ends in an omega turn with a probability that rises with how far the animal backed up, read from Gray et al.'s measured curve: rare after a single backward bend, near-certain after four. Stronger stimuli hold the reversal longer through the command balance itself, so harsh touch earns both a longer retreat and a sharper turn without either being scripted to. Escape vigor is latched at reversal onset from the command excess, the published AVA-transient relationship; the omega turn coils the anterior body and reorients it by about 133 degrees, the measured figure. The turn comes from a travelling wave running along a gently curved body rather than from a deep static bend: bending harder saturates the muscle targets, kills the wave and the thrust with it, and the animal spins in place.
Monoamines do not travel down the wired connectome. A cell that makes dopamine releases it into the tissue and every cell carrying a cognate receptor responds, synaptic partner or not, so they are a second layer: 2,626 ligand-receptor edges of which only 6% are also chemical synapses (Bentley et al. 2016). Each receptor carries the sign of its measured coupling, so DOP-3 (Gi) inhibits where DOP-1 (Gq) excites on the same cell, and the ligand-gated chloride channels inhibit directly.
Basal slowing falls out of it. Food contact excites the eight dopaminergic
cells, dopamine reaches the cholinergic motor neurons through DOP-3, and the
animal slows 13.9% on encountering a lawn, inside the measured band. It is
mechanism rather than a formula, and the knockouts say so: cat-2 slows 0.1%
because it makes no dopamine, tph-1 slows 16.1% because serotonin is not
what carries this response, and dop-1 slows more than wild type because
removing the excitatory receptor leaves DOP-3 unopposed. Receptor genes are
therefore experimental tools here, not inert annotations.
The layer is deliberately quiet at rest. Release is measured as a deviation from the animal's own slow baseline, so an undisturbed animal receives no net modulation and the resting operating point every other constant is calibrated against does not move.
Thirty-one loci are mapped onto the subsystems their products implement. Knockouts reach only the cells that CeNGEN single-cell RNA-seq measures the gene in:
| Gene | Expressed in | Effect |
|---|---|---|
mec-4 |
the six touch receptor neurons | gentle touch abolished, harsh touch intact |
unc-25 |
28 cells: DD, VD, RME, AVL, DVB, RIS, RIB | GABA lost, animal hypercontracts |
che-1 |
ASEL, ASER | salt sensing lost, odour intact |
cat-2 |
the eight dopaminergic neurons | no dopamine: basal slowing and area-restricted search both lost |
daf-2 |
158 cells | lifespan roughly doubles, requires daf-16 |
worm gene <name> resolves any of the 46,926 annotated loci to its WormBase ID,
chromosome and coordinates.
Alt-click any cell in the network view to kill it: it stops sending and receiving, and the surviving network's resting state is re-solved around the loss.
| Ablation | Result |
|---|---|
| AVB + PVC | forward drive falls to 0.00, reversals intact |
| AVA + AVD + AVE | touch-evoked reversal abolished |
| ALM + AVM | anterior touch sensitivity lost |
All 448 cells laid out sensory to interneuron to motor to muscle, ordered to minimise edge crossings, with node brightness tracking live drive. Hover any cell for its transmitter, current drive and strongest partners with weights. Pin it, or watch it in the trace panel to see its activation over the last 30 seconds.
Runs from fertilised egg to death on measured timings: 14.2 h of embryogenesis with milestones, 50.7 h from hatch to adult across four larval stages, dauer entry under crowding and scarcity, a sperm-limited brood of ~300 over ~5 days, then senescence and death at a lifespan that scales with temperature and genotype.
Each reports the metric its original paper reports and carries that paper's reference value.
| Assay | Measures |
|---|---|
chemotaxis |
chemotaxis index on a salt gradient |
thermotaxis |
drift relative to remembered cultivation temperature |
touch-habituation |
response decrement over repeated taps |
basal-slowing |
speed drop on encountering food |
touch-response |
reversal probability by body position |
lifespan |
egg to death, with brood size and reproductive period |
CSV or JSON of trajectory, behavioural state, developmental stage and named
neuron activations, with fixed seeds. worm batch compares genotypes across
replicates.
Environment gradients, bacterial lawn, temperature, oxygen, touch
|
SensorySystem modality -> named neurons, via receptive fields, gated by genes
|
NervousSystem 448 cells, graded-potential ODEs over the real connectome
|
Simulation reads command interneurons -> behavioural state machine
|
Muscle pacer the scripted wave current -> 95 REAL muscle cells
|
Body muscle calcium -> force -> viscoelastic body
|
resistive force theory -> movement -> back to Environment
C. elegans neurons do not spike; they are isopotential, graded-release cells. The model is the standard leaky-integrator formulation of Wicks et al. (1996) and Kunert et al. (2014):
C dV_i/dt = -G_leak(V_i - E_leak,i) - I_gap_i - I_syn_i + I_ext_i
I_gap_i = sum_j g_gap * Gg[i,j] * (V_i - V_j)
I_syn_i = sum_j g_syn * Gs[i,j] * s_j * (V_i - E_ij)
ds_j/dt = a_r * phi(V_j) * (1 - s_j) - a_d * s_j
Integration is exponential Euler, unconditionally stable, at roughly 4x real time on a laptop. The per-cell activation threshold is solved as a linear system so the resting network sits at its own equilibrium. Passive properties follow patch clamp: a 0.25 nS leak for a 4 GOhm input resistance, and 3 pS per gap-junction contact, since measured coupling is reported whole-cell across all contacts a pair shares. Leak reversals are solved so the network equilibrium lands on measured resting potentials.
The 95 body-wall muscles are cells in the same network and carry their own measured passive properties: they rest at -25 mV against a neuron's -65 mV, have a capacitance of 70 pF against 1.5 pF, and a membrane time constant of 70 ms against 6 ms. The depolarised rest reflects a high chloride permeability rather than a potassium equilibrium.
Muscle force follows calcium rather than membrane potential, so each muscle carries a calcium stage: two first-order filters whose combined impulse response is the measured transient, rising with a 250 ms and decaying with an 880 ms time constant and peaking 0.44 s after excitation. Contractile calcium in this animal comes from sarcoplasmic release through the ryanodine receptor UNC-68 gated by EGL-19. Calcium here is normalised drive, not a concentration: no C. elegans muscle calcium measurement has ever been calibrated to nM or uM.
At the neuromuscular junction, acetylcholine acts on a non-selective cation channel reversing near 0 mV and GABA on the chloride-permeant UNC-49 receptor reversing near -30 mV, so against a -25 mV resting potential GABA contributes 5 mV of hyperpolarising drive and acts largely by shunting. The per-contact neuromuscular conductance is calibrated so that a muscle's achievable whole-cell cholinergic conductance matches the 8.5 nS measured by patch clamp. Achievable rather than nominal matters here: the synaptic release variable cannot exceed a_r/(a_r + a_d), so a synapse delivers at most a sixth of its per-contact conductance and spans only 1.83x from rest to saturation.
Muscle fires all-or-none calcium action potentials, and those spikes are what drive contraction. The inward conductance is measured twice over: Jospin's peak EGL-19 density of 199 S/F at 70 pF gives 13.9 nS, and the measured maximum upstroke rate of 1.38 V/s across 70 pF needs 9.2 nS against the 8.9 nS the steady-state density gives. Inactivation is partial, and its residual is measured too, the maintained component being 127 S/F of the 199 S/F peak. The repolarising side is fitted, since neither SHK-1 nor SLO-2 has a published body-wall muscle current-voltage relation; it is fitted to the measured waveform, reproducing a 45.6 mV spike of 18.7 ms half-width against a measured 45 to 53 mV and 15.5 to 20 ms.
| Module | Role |
|---|---|
worm/genome.py |
annotation, gene lookup, knockouts, expression |
worm/connectome.py |
wiring to conductance matrices, network layout |
worm/nervous_system.py |
graded-potential dynamics, ablation |
worm/sensory.py |
environment to current, mechanosensory receptive fields |
worm/modulation.py |
slow monoamine layer: volume transmission by receptor |
worm/body.py |
oscillator, muscle to curvature, low-Reynolds locomotion |
worm/kinematics.py |
gait measurement: frequency, wavelength, wave direction |
worm/lifecycle.py |
embryo, larval stages, dauer, feeding, ageing, death |
worm/simulation.py |
closed loop, escape-response state machine |
worm/assays.py |
standard assays with reference values |
worm/validate.py |
52 checks: 34 behavioural, 18 consistency, gaps as expected failures |
worm/parameters.py |
audited parameter registry, provenance tags enforced by a check |
worm/server.py, viewer/ |
live browser viewer |
| Dataset | Source | Contents |
|---|---|---|
| Genome annotation | NCBI RefSeq GCF_000002985.6 (WBcel235) | 46,926 genes, 19,983 protein-coding |
| Connectome | Cook et al., corrected July 2020 release, via OpenWorm ConnectomeToolbox | 473 cells, 7,762 edges (302 neurons, 95 body-wall muscles) |
| Developmental connectomes | Witvliet et al. 2021, via OpenWorm ConnectomeToolbox | 8 reconstructions, L1 to adult, 858 to 2,496 edges (data only, issue #27) |
| Neuron metadata | OpenWorm owmeta | type and transmitter for 302 neurons |
| Expression | CeNGEN via wormneuroatlas | 130 genes cached per neuron class: knockout loci, ligand-gated receptors, and 35 ion channels |
| Cell classification | WormAtlas | lineage and anatomical class |
| Receptor pharmacology | derived from RefSeq product descriptions | 72 ligand-gated receptors with ion selectivity |
| Monoamine connectome | Bentley et al. 2016, via OpenWorm ConnectomeToolbox | 2,626 extrasynaptic edges naming ligand and receptor |
| Neuropeptide connectome | Bentley et al. 2016, via OpenWorm ConnectomeToolbox | 8,931 extrasynaptic edges, 15 ligands, 12 receptors (data only, issue #13) |
| Functional atlas | Randi et al. 2023, bundled with wormneuroatlas | measured signal propagation between 300 neurons, used to bound what the wiring predicts (docs/citations.md) |
Sources are audited for peer review and corrections by
scripts/audit_citations.py, with the findings in
docs/citations.md.
The datasets disagree in specific ways, each handled in code where it arises:
gap junctions are listed in both directions, so the matrix is filled directly
rather than symmetrised; cell naming differs between sources and is normalised;
owmeta leaves 57 neurons unannotated, which come from the systematic transmitter
atlases; and cells that stain GABA-positive but lack unc-25 take GABA up
rather than making it, so are not modelled as GABAergic.
CLAIMS.md maps every claim here to the mechanism producing it, tagged measured, published, tuned or scripted, so the difference between what the model knows and what it assumes stays visible.
worm validate runs 52 checks against published measurements: 34 behavioural
(the animal is run and measured) and 18 consistency checks (parameter and data
invariants). 41 pass. Ten are registered expected failures, each naming the
gap it tracks. The connectome does not generate the locomotor rhythm, so real
muscle drive carries no undulation, and the fixed-frequency oscillator cannot
adapt gait to the medium
(issue #10). The animal
reverses spontaneously at the measured rates, searches locally after leaving
food and turns with real 133-degree omega turns, but it does not yet
chemotax: on honest plate geometry the biased walk cannot out-drift a
salt-blind animal, which is an expected failure owned by
issue #20. goa-1 also
still loses to its constant reversing the speed its deeper, faster bends
would otherwise gain, an oscillator-depth gap owned by
issue #10. Muscle
activation also leads curvature by 8 degrees where the animal holds about 45.
| Check | Model | Published |
|---|---|---|
| Input resistance | 4.0 GOhm | 1.6 to 8 GOhm |
| Membrane time constant | 6.0 ms | 3 to 10 ms |
| AVAL-AVAR gap coupling | 54 pS | 56 pS |
| VA5 / VB6 resting potential | -71.7 / -53.2 mV | -71.7 / -53.2 mV |
| Crawling speed | 0.204 mm/s | 0.20 +/- 0.04 mm/s |
| Undulation amplitude | 17.9% body length | 19.3% |
| Undulation frequency | 0.468 Hz | 0.47 Hz commanded, recovered from the body |
| Omega turn reorientation | 133 degrees | about 140 |
| Spontaneous reversals off food | 2.3 /min | ~2 /min, on food lower, goa-1 higher |
| Basal slowing on food | 13.9% (cat-2 0.1%, tph-1 16.1%) |
slowing present, abolished without dopamine |
| Chemotaxis index, salt | +0.50 (che-1 -0.83) |
positive for wild type, absent without ASE |
| Local search vs dispersal | 1.8 vs 0.8 /min, cat-2 stays at 0.4 |
several-fold decay over ~30 min, dopamine-dependent |
| Embryogenesis | 14.2 h | 14.2 h |
| Hatch to adult | 50.8 h | 50.67 +/- 1.95 h |
| Adult lifespan | mean 15.9 d, sd 3.3 d over a cohort | 15.2 +/- 3.6 d |
| Self-fertile brood | 300 | ~327, sperm-limited |
daf-2 lifespan |
31.3 d (2x the animal's own draw) | ~29.5 d |
The other behavioural checks cover touch responses by body position, the
mec-4/mec-10 dissociation, the unc-25/unc-47/unc-49 shrinker class,
unc-13 paralysis, the opposing goa-1 and egl-30 phenotypes, tdc-1
omega-turn loss, and command-interneuron ablation. The consistency checks pin
the daf-16 epistasis, che-1 modality gating, developmental timings, and
the sperm-limited brood.
Every parameter the model is told is collected in one audited registry
(worm params), tagged measured, published, tuned or scripted; the scripted
tags are the ones the open issues exist to delete.
Independently, the 26 GABAergic neurons the pipeline derives from transmitter data match the known count exactly (6 DD + 13 VD + 4 RME + AVL + DVB + RIS).
Measured data: connectivity and synapse counts, transmitter identity, gene expression, receptive field extents, passive membrane properties, resting potentials, developmental timings, body sizes, brood size, lifespan.
Standard published models: graded-potential dynamics (Wicks 1996 / Kunert 2014), resistive force theory for low-Reynolds locomotion.
Approximations:
- The locomotor rhythm is imposed, not emergent, and it is imposed at the end organ. No published model produces this rhythm from the connectome and no ventral cord motor neuron has ever been recorded during locomotion, so one scripted current carries the wave: per-muscle currents into the 95 real muscle cells, at the measured frequency and wavelength (Cronin et al. 2005), switching direction with the command state as B- and A-class activity does (Haspel et al. 2010; Kawano et al. 2011). Everything downstream is real: muscle calcium with measured kinetics, force, mechanics, so ablating muscle bends the animal and GABA loss produces the shrinker through genuine co-contraction (McIntire et al. 1993). Imposing the rhythm one level higher, as currents into the motor neurons, was built and measured out: the current leaks into the command interneurons through their measured gap junctions and destroys touch discrimination, with mec-4 reading as wild type on every detector tried. Imposing it one level lower, as prescribed body curvature, leaves the muscles decorative. The end organ is the smallest scripted surface that keeps every assay readable, and docs/emergent-cpg.md records the attempts to shrink it further.
- Enhanced slowing is still a scalar. The serotonergic response of a food-deprived animal needs serotonin release to depend on feeding history, which the monoamine layer does not model yet, so it stays a labelled formula. Basal slowing no longer is: it was a scalar until the monoamine layer gave it a pathway (issue #11).
- The peptidergic layer is fetched but not built. Bentley's 8,931 neuropeptide edges are pinned alongside the monoamine ones and unused; that is the second half of issue #13.
- Initiative is generated, not emergent. Spontaneous reversals come from
a Poisson generator at the measured rates injected into the real backward
command cells, and klinokinesis scales that rate with the measured
asymmetry as a stand-in for the ASE-to-command loop the graded network
cannot yet close (issue #7).
Both are labelled scripted. The decision machinery they feed is real, which
is why
che-1,tax-4andgoa-1move these behaviours by mechanism. - Muscle spikes are not reached from synaptic input. Muscle carries the measured calcium action potential, but crossing its -10 mV threshold needs about 2.4 nS of extra excitatory conductance, close to the 2.26 nS implied by the measured 67.9 pA trigger current, and one junction spans only 1.83x from rest to saturation. Propagation along the body is therefore still subthreshold and graded rather than spike-mediated, which is why an imposed bend propagates at slope 0.364 rather than the measured 0.62. docs/emergent-cpg.md sets out what an emergent version requires. No published model produces C. elegans locomotion emergently from the connectome.
- Synapse signs are derived per edge from the postsynaptic cell's measured
receptor expression (CeNGEN): which ligand-gated channels a cell transcribes,
and whether those are cation or anion channels, sets each synapse's sign.
The receptor table itself is derived from the RefSeq product descriptions
(
scripts/build_receptors.py). Where expression cannot decide (metabotropic transmitters, cells outside CeNGEN, ties), a transmitter-level heuristic is the tagged fallback. A small table of documented exceptions overrides both where behaviour settles a sign that expression cannot: PLM onto the backward command interneurons is inhibitory, since tail touch drives forward escape and PLM ablation abolishes it, and acetylcholine gates chloride through the ACC and LGC families that CeNGEN does not resolve in those cells. Overrides are counted separately in the sign provenance. - The genome sequence is not load-bearing. The annotation drives gene lookup and knockouts, but the 100 Mb of sequence yields chromosome lengths and GC content. Mapping a gene to what its loss does is a curated table.
- Escape is a state machine. Reversal and omega turn have separable motor pathways; the network decides when each fires.
- The 24-segment body is a coarse-graining. The animal has 95 body-wall muscles in quadrants of 24/24/24/23, staggered into eight longitudinal rows rather than transverse rings, which Hall notes amounts to roughly twelve segments. Muscle index is mapped proportionally onto segments, preserving anterior-posterior order without claiming a ring. The 4x24 grid some simulators use is an idealisation, not anatomy.
- Innervation is treated as uniform along the body, and is not. The anterior 16 muscles receive nerve-ring input only, the next 16 receive both ring and cord, and only the posterior 63 are on the cord alone (White et al. 1986). The head is a separate oscillator in the animal, and muscle arms reach only the nearest cord, which is the structural reason the body is restricted to dorsoventral waves.
- The posterior body is the reconstruction's thinnest region, and it is where the wave has to travel. Muscles in body rows 17 to 24 average 6.3 presynaptic partners against about 10 published, while head and neck sit at 10.0 and 12.8, and sublateral input to posterior muscle is absent entirely. Cook et al. report a remaining gap "in a region of the posterior body where there are no high-power EM series from either sex", and state that gaps leaving cells without innervation are "unquestionably artefactual". A wiring-derived model cannot propagate a wave through a region the wiring is missing from, so part of the locomotion gap is a limit of the available data rather than of the model.
- About 29% of neuromuscular input in the dataset was never EM-reconstructed. The sublateral motor neurons (SMB, SMD, SIA, SIB) were recorded by immunofluorescence and sampling rather than serial section, and White et al. reported almost no synapses on those processes. Muscle-muscle gap junctions are similarly incomplete, carrying almost no left-right coupling where White describes it through the muscle arms.
- Not modelled: pharynx, gonad, intestine, embryonic lineage, hydrodynamics beyond RFT. One animal, so crowding is a scalar.
Connectome
- White, Southgate, Thomson & Brenner (1986), Phil. Trans. R. Soc. B 314:1
- Bentley et al. (2016), PLoS Comput. Biol. 12:e1005283 (monoamine and neuropeptide extrasynaptic networks)
- Chase, Pepper & Koelle (2004), Nat. Neurosci. 7:1096 (DOP-3 on cholinergic motor neurons carries basal slowing)
- Cook et al. (2019), Nature 571:63
- Witvliet et al. (2021), Nature 596:257
- OpenWorm ConnectomeToolbox · c302 · owmeta
Neural dynamics and electrophysiology
- Wicks, Roehrig & Rankin (1996), J. Neurosci. 16:4017
- Kunert, Shlizerman & Kutz (2014), Phys. Rev. E 89:052805
- Goodman, Hall, Avery & Lockery (1998), Neuron 20:763 (input resistance, capacitance)
- Liu, Chen & Wang (2014), Nat. Commun. 5:5155 (motor neuron resting potentials)
- Liu, Chen & Wang (2020), Nat. Commun. 11:5076 (gap junction conductance)
- Shindou et al. (2019), Sci. Rep. 9:3430
- Jospin et al. (2002), J. Cell Biol. 159:337 (calcium reversal; muscle resting potential -19.7 mV and input resistance 1.0 GOhm)
- Gao & Zhen (2011), PNAS 108:2557 (muscle resting potential -25.0 mV, calcium action potentials, 67.9 pA trigger current)
- Richmond (2006), WormBook (neuromuscular junction recording; muscle capacitance ~70 pF)
- Richmond & Jorgensen (1999), Nat. Neurosci. 2:791 (one GABA and two acetylcholine receptors at the NMJ; 774 pA acetylcholine response, chloride-permeant UNC-49)
- C. elegans Neural Interactome
Transmitters and expression
- Pereira et al. (2015), eLife 4:e12432 (cholinergic)
- Serrano-Saiz et al. (2013), Cell 155:659 (glutamatergic)
- Gendrel, Atlas & Hobert (2016), eLife 5:e17686 (GABAergic)
- Taylor et al. (2021), Cell 184:4329 (CeNGEN)
- Randi et al. (2023), Nature 623:406 (wormneuroatlas)
Locomotion
- Boyle, Berri & Cohen (2012), Front. Comput. Neurosci. 6:10
- O'Hagan, Chalfie & Goodman (2005), Nat. Neurosci. 8:43 (mechanoreceptor currents: phasic, onset and offset, tens-of-ms adaptation)
- Rankin, Beck & Chiba (1990), Behav. Brain Res. 37:89 (tap habituation: decrement and recovery)
- Raizen, Lee & Avery (1995), Genetics 141:1365 (eat-2 pharyngeal pumping deficit, the mechanism of its dietary restriction)
- Wicks & Rankin (1995), J. Neurosci. 15:2434 (the tap response integrates antagonistic reflexes)
- Wicks & Rankin (1997), Behav. Neurosci. 111:342 (habituation localises to the touch cells' output synapses)
- Wen et al. (2012), Neuron 76:750 (proprioceptive coupling)
- Haspel, O'Donovan & Hart (2010), J. Neurosci. 30:11151 (B-class active in forward, A-class in backward locomotion)
- Kawano et al. (2011), Neuron 72:572 (A/B activity balance sets direction)
- McIntire, Jorgensen, Kaplan & Horvitz (1993), Nature 364:337 (GABA loss produces the shrinker)
- Sulston & White (1980), Dev. Biol. 78:577 (muscle ablation causes local body-shape defects)
- Mellem, Brockie, Madsen & Maricq (2008), Nat. Neurosci. 11:865 (RMD plateau potentials, a measured regenerative response in a head motor neuron)
- Byerly, Cassada & Russell (1976), Dev. Biol. 51:23 (development rate versus temperature)
- Gao et al. (2018), eLife 7:e29915 (A-class oscillators)
- Kawano et al. (2011), Neuron 72:572
- Deng et al. (2021), eNeuro 8:ENEURO.0241-20.2020
- Cronin et al. (2005), BMC Genet. 6:5 (gait metrics)
- Fang-Yen et al. (2010), PNAS 107:20323
- Butler et al. (2015), J. R. Soc. Interface 12:20140963 (muscle calcium transient, activation-to-curvature phase)
- Liu et al. (2011), J. Physiol. 589:101 (muscle action potentials, UNC-68 calcium release)
Musculature and the neuromuscular junction
- Sulston & Horvitz (1977), Dev. Biol. 56:110 (post-embryonic lineage; 95 muscles, 24/24/24/23 quadrants)
- White, Southgate, Thomson & Brenner (1986), Phil. Trans. R. Soc. B 314:1, Fig. 10 (eight staggered rows; head/neck/body innervation)
- WormAtlas Muscle System (Altun & Hall) · WormBook: body wall muscle
- Dixon & Roy (2005), Development 132:3079 (muscle arms; ~4 per cell in the adult, one cord only)
- Liu, Chen, Gaier, Joshi & Wang (2006), J. Biol. Chem. 281:7881 (muscle-muscle gap junctions, 350 pS or less)
- Liu et al. (2013), PLoS ONE 8:e76877 (six innexins couple body-wall muscle)
Mechanosensation and escape
- Chalfie & Sulston (1981), Dev. Biol. 82:358 · Chalfie et al. (1985), J. Neurosci. 5:956
- Arnadottir et al. (2011), J. Neurosci. 31:12695
- Li, Kang, Piggott, Feng & Xu (2011), Nat. Commun. 2:315 (harsh touch)
- Husson, Steuer Costa et al. (2012), Curr. Biol. 22:743
- Donnelly et al. (2013), PLoS Biol. 11:e1001529
- Pirri et al. (2009), Neuron 62:526
Chemosensation and navigation
- Chalasani et al. (2007), Nature 450:63 (carries a 2016 corrigendum; the part we use survives it, see docs/citations.md)
- Pierce-Shimomura, Morse & Lockery (1999), J. Neurosci. 19:9557
- Iino & Yoshida (2009), J. Neurosci. 29:5370 (klinotaxis and klinokinesis as parallel salt-chemotaxis mechanisms)
- Broekmans, Rodgers, Ryu & Stephens (2016), eLife 5:e17227 (deep body bends of the omega turn)
- Gray, Hill & Bargmann (2005), PNAS 102:3184 (spontaneous reversal rates on and off food; local search decays to dispersal)
- Hills, Brockie & Maricq (2004), J. Neurosci. 24:1217 (area-restricted search requires dopamine)
- Segalat, Elkes & Kaplan (1995), Science 267:1648 (goa-1 hyperreversal)
- Iino & Yoshida (2009), J. Neurosci. 29:5370
- Gray, Hill & Bargmann (2005), PNAS 102:3184
- Sawin, Ranganathan & Horvitz (2000), Neuron 26:619
Genetics and phenotypes
- Brenner (1974), Genetics 77:71
- Jin, Jorgensen, Hartwieg & Horvitz (1999), J. Neurosci. 19:539
- Bamber et al. (1999), J. Neurosci. 19:5348
- Richmond, Davis & Jorgensen (1999), Nat. Neurosci. 2:959
- WormBook: GABA · Acetylcholine · Mechanosensation · Chemosensation
Life cycle and ageing
- Sulston, Schierenberg, White & Thomson (1983), Dev. Biol. 100:64
- Faerberg, Gurarie & Ruvinsky (2022), BMC Biol. 20:87
- Cassada & Russell (1975), Dev. Biol. 46:326 · Golden & Riddle (1984), Dev. Biol. 102:368
- Hodgkin & Barnes (1991), Proc. R. Soc. B 246:19 · Ward & Carrel (1979)
- Huang, Xiong & Kornfeld (2004), PNAS 101:8084
- Herndon et al. (2002), Nature 419:808
- Kenyon et al. (1993), Nature 366:461 · Lakowski & Hekimi (1998), PNAS 95:13091
- Baugh (2013), Genetics 194:539
Reference resources
MIT, code only. No datasets are redistributed; fetch_data.py pulls each from
its publisher and they remain under their own terms. If you use this for
research, cite the primary sources above rather than this repository.

