🪰 Fly Whisperer
Two things you can do with a real fruit fly's wiring. Sneak up on it, then teach it what to like. The synapses are FlyWire's, and nothing here was trained with gradients.
Pick a smell, then give the fly sugar or a shock while it smells it. Dopamine neurons erase the synapses of whichever Kenyon cells were firing. Then see what it picks.
What is real here?
Sneak up. The escape circuit has 44,743 neurons and 2 million synapses: every visual projection, central and descending neuron in FlyWire v783. The optic lobe is replaced by an explicit expansion detector, because the annotation has no retinotopy. It drives the looming cells LPLC2, LC4 and LC6, and from there every synapse is the connectome's, signs included. The giant fiber, DNp01, is read out as takeoff.
Fly school. The mushroom body has 8,572 neurons: smell receptors, projection neurons, 5,177 Kenyon cells, the APL and DPM neurons, 96 output neurons and 331 dopamine neurons. The output neurons that a reward neuron teaches count as avoidance, and the ones a punishment neuron teaches count as approach, following Aso et al. 2014. Odors are invented patterns of glomeruli, and Kenyon-to-Kenyon synapses are dropped.
Both are rate models, not spikes, and neither has been checked against recordings. Wiring from FlyWire v783 (Dorkenwald et al., Nature 2024; Shiu et al., Nature 2024) with cell types from Schlegel et al., Nature 2024. FlyWire's non-commercial terms apply.