Developer Couples 139,255-Neuron Fly Brain Simulation to 1-Billion-Parameter Language Model

A developer has wired a 139,255-neuron fruit fly brain simulation to a 1-billion-parameter language model so that a chat message is treated as a sensory stimulus, the simulated brain runs, and the resulting neural activity is used to generate a reply. The demonstration uses 139,255 neurons and 2.7 million connections—the neuron count of the adult female *Drosophila melanogaster* brain reconstructed by the FlyWire Consortium—and a compact language model that reads the activity pattern after each run. The same developer said the fly would appear on a YouTube livestream so viewers can talk to it in real time.