www.lesswrong.com/posts/ybwcxBRrsKavJB9Wz/no-we-haven-t-uploaded-a-fly-yet
1 correction found
published a model of the entire adult fly brain in which every neuron and neural connection was represented
Shiu et al.'s 2024 model was not a full model of every neuron and connection in the adult fly brain. The paper says it was built from the adult Drosophila central brain connectome and modeled about 127,400 neurons, whereas the whole-brain FlyWire connectome contains 139,255 neurons.
Full reasoning
The cited 2024 Nature paper by Shiu et al. does not claim to model every neuron and connection in the adult fly brain.
Their abstract says the work is based on the adult Drosophila melanogaster central brain connectome, not the full adult brain. In the main text, the authors again write that they use connection weights derived from the entire adult Drosophila central brain connectome. Later in the paper they state: "Of the 127,400 neurons modelled..."
That is materially smaller than the full FlyWire whole-brain connectome published in the same Nature package, which reports 139,255 neurons for a whole adult brain and explicitly says that all neurons in the central brain and both optic lobes were segmented and proofread.
So the LessWrong post overstates what Shiu et al. represented. A more accurate description would be that Shiu et al. published a large-scale connectome-based model built from the adult fly central brain connectome, not a model containing every neuron and neural connection in the entire adult fly brain.
2 sources
- A Drosophila computational brain model reveals sensorimotor processing | Nature
Abstract: "The recent assembly of the adult Drosophila melanogaster central brain connectome, containing more than 125,000 neurons..." Main text: "we implement a simple leaky integrate-and-fire model using the connection weights derived from the entire adult Drosophila central brain connectome" and later, "Of the 127,400 neurons modelled..."
- Neuronal wiring diagram of an adult brain | Nature
The whole-brain connectome paper reports "a whole brain containing ... 139,255 neurons" and states: "All neurons in the central brain and both optic lobes were segmented and proofread."