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Library / Fruit fly (synthetic demo)
Drosophila melanogaster

Fruit fly (synthetic demo)

A 5,000 neuron stand in for the fly brain with realistic circuit layout (vision, smell, memory, navigation, escape) and invented numbers. Fast enough to experiment with in the browser.

Teaching brain, invented numbersGenerated by pipeline/make_synthetic_fly.py (seed 42)
Stimulate and silence cellsSee it in an experiment
5,236
neurons
34
cell types
50,128
chemical pairs
0
gap junction pairs
627,323
synapses

Who talks to whom

Synapses between neuron classes. Cells show the share of the sending class's output.

sensoryopticvisual projectioncentraldescendingascendingmotorsensoryopticvisual projectioncentraldescendingascendingmotorsensory → sensory: 0 synapses (0.0% of output)sensory → optic: 105,261 synapses (48.9% of output)49%sensory → visual projection: 0 synapses (0.0% of output)sensory → central: 103,768 synapses (48.2% of output)48%sensory → descending: 6,285 synapses (2.9% of output)3%sensory → ascending: 0 synapses (0.0% of output)sensory → motor: 0 synapses (0.0% of output)optic → sensory: 0 synapses (0.0% of output)optic → optic: 143,637 synapses (88.6% of output)89%optic → visual projection: 15,332 synapses (9.5% of output)9%optic → central: 0 synapses (0.0% of output)optic → descending: 3,111 synapses (1.9% of output)2%optic → ascending: 0 synapses (0.0% of output)optic → motor: 0 synapses (0.0% of output)visual projection → sensory: 0 synapses (0.0% of output)visual projection → optic: 0 synapses (0.0% of output)visual projection → visual projection: 0 synapses (0.0% of output)visual projection → central: 0 synapses (0.0% of output)visual projection → descending: 12,861 synapses (100.0% of output)100%visual projection → ascending: 0 synapses (0.0% of output)visual projection → motor: 0 synapses (0.0% of output)central → sensory: 1,815 synapses (0.9% of output)central → optic: 0 synapses (0.0% of output)central → visual projection: 0 synapses (0.0% of output)central → central: 205,018 synapses (97.4% of output)97%central → descending: 3,731 synapses (1.8% of output)2%central → ascending: 0 synapses (0.0% of output)central → motor: 0 synapses (0.0% of output)descending → sensory: 0 synapses (0.0% of output)descending → optic: 0 synapses (0.0% of output)descending → visual projection: 0 synapses (0.0% of output)descending → central: 0 synapses (0.0% of output)descending → descending: 0 synapses (0.0% of output)descending → ascending: 0 synapses (0.0% of output)descending → motor: 19,395 synapses (100.0% of output)100%ascending → sensory: 0 synapses (0.0% of output)ascending → optic: 0 synapses (0.0% of output)ascending → visual projection: 0 synapses (0.0% of output)ascending → central: 5,095 synapses (82.5% of output)83%ascending → descending: 1,080 synapses (17.5% of output)17%ascending → ascending: 0 synapses (0.0% of output)ascending → motor: 0 synapses (0.0% of output)motor → sensory: 0 synapses (0.0% of output)motor → optic: 0 synapses (0.0% of output)motor → visual projection: 0 synapses (0.0% of output)motor → central: 0 synapses (0.0% of output)motor → descending: 0 synapses (0.0% of output)motor → ascending: 934 synapses (100.0% of output)100%motor → motor: 0 synapses (0.0% of output)from ↓ to →

Neuron classes

How the system divides its neurons.

sensory920
optic1,658
visual projection260
central2,070
descending128
ascending80
motor120

Transmitters

Green excites, blue inhibits, grey is modulatory or unknown in this model.

ACH3,996
GLUT480
GABA440
HA240
DA80

Cell types

Sorted by total synapses. Use these names in the lab.

Cell typeClassTransmitterNeuronsSynapses inSynapses out
uPNcentralACH12098,14651,331
R1-6sensoryHA2400105,261
CBcentralACH50074,97620,838
ORNsensoryACH4001,81590,926
KCcentralACH80044,30441,435
L2opticACH20051,25428,398
L1opticGLUT20054,00721,767
MBONcentralGLUT4048,41918,392
T4opticACH32044,96217,460
Tm3opticACH20018,07628,549
Mi1opticACH20017,41727,465
T5opticACH32026,04017,833
Mi9opticGLUT20014,67217,497
CB_inhcentralGABA3009,99919,485
EPGcentralACH4611,82316,007
LNcentralGABA808,56017,595
GFdescendingACH213,4406,888
LPLC2visual projectionACH16012,8236,539
PAMcentralDA801,64713,774
VSopticACH1212,7662,320
MN_legmotorACH8013,523934
JOsensoryACH160013,421
PENcentralACH406,3266,036
Delta7centralGLUT406,4054,202
HSopticACH69,704791
DNgdescendingGABA607,1032,573
LC4visual projectionACH1002,5096,322
DNpdescendingACH604,1764,335
ANascendingACH809346,175
MN_wingmotorACH405,8720
BMsensoryACH12005,706
MDNdescendingACH48804,590
PFL3centralACH243,2761,469
DNa02descendingACH21,4691,009

Hub neurons

The most connected individual cells.

NeuronTypeSynapses
…069473GF10,863
…069973GF9,465
…807845MBON1,969
…806747MBON1,953
…802854MBON1,916
…346755uPN1,907
…806918MBON1,895
…796749MBON1,888
…944489HS1,880
…944894HS1,865
…803646MBON1,858
…808128MBON1,849
…942907HS1,848
…807620MBON1,846
…325778uPN1,837

Read before you conclude

What this dataset and model can and cannot tell you.

  • Synthetic data. Cell type names are real, the wiring numbers are invented.
  • Use the FlyWire importer to run the same experiments on the real brain.

Cite

Generated data, MIT

  • Circuit layout inspired by: Dorkenwald, S. et al. (2024). Neuronal wiring diagram of an adult brain. Nature 634, 124-138.
  • Simulation parameters from: Shiu, P. K. et al. (2024). A Drosophila computational brain model reveals sensorimotor processing. Nature 634, 210-219.