A fly brain keeps a simulated human body on its feet, under fire from balls and over logs.
10/10Falls that end standingback on its feet in 1.2 s (median)
0.31Falls per minutemeasured in the browser, 32 runs
59.1 mDistance per minuteunder ball fire
98%Uprightof the time, under ball fire and over logs
Walking runs through the fly’s central brain and its steering neurons
The fly brain keeps the body upright with its central brain and the command neurons that steer a walking fly. Its most active command pair is DNb05, a neuron whose left–right activity follows a walking fly’s turns (Yang et al., 2024); switch this single pair off and the body falls five times as often.
Yang, H. H. et al. (2024). Fine-grained descending control of steering in walking Drosophila. Cell 187, 6290–6308. doi:10.1016/j.cell.2024.08.033
In the fly brain
The body's state reaches the fly brain the way its own body reports in; the muscles are driven from the neurons that carry its commands.
Senses
Fly brain138,639neurons15.1 millionconnections
Where signals enter
1,299 descending neuronsCommands