A fly asleep

Tainton-Heap, L.A.L., et al. Curr Biol https://doi.org/10.1016/j.cub.2020.10.081 (2020)

Sleep isn’t not a single phenomenon; the act takes a number of different forms and functions, the differences and purposes of which are still being determined. Fruit flies are no strangers to sleep, and researchers have been using Drosophila to probe the secrets of slumber.

In a study published in Current Biology, a team at the University of Queensland recorded and manipulated neurons in the fly dorsal fan-shaped body (dFB), a region shown to promote a sleep state in the fly. They observed distinct stages: wakefulness, deep sleep, early sleep, and active sleep, each with different patterns of active neurons and transitions from one stage to another. At times, the flies’ brains appeared active, even though they remained unresponsive to stimuli—a paradox that’s been observed in other sleeping animals, including humans.