During sleep, a fly's brain filters visual information in a rhythmic manner, ensuring the insect remains upright, according to research.

In a groundbreaking study published in Nature, a team of researchers led by neurophysiologist David Owald, with co-authors Davide Raccuglia and Raquel Suaréz-Grimalt, have delved into the intricate neurological processes of sleep in fruit flies (Taufliegen). The team, hailing from Charité's Institute of Neurophysiology, discovered a fascinating mechanism that could potentially reveal a universal principle of sleep.

During sleep, the electrical voltage of nerve cells in flies oscillates once per second. Interestingly, the fly's brain finely attunes activating and inhibiting networks during this period. One network activates, enabling the fly to respond to visual stimuli, while the other inhibits this response.

However, during a short window of time, strong visual stimuli can overcome the inhibitory brain network and wake a fly up. This suggests that the draught, or transmission of stimuli, is interrupted during sleep but a strong gust of wind, or strong stimulus, can wake the animal up.

The study elucidated that slow, synchronous electrical waves known as slow waves connect visual stimuli with brain regions required for navigation in flies during sleep. These slow waves create an opportunity for intense stimuli to wake up a sleeping fly. Rhythmic fluctuations in these electrical waves make it possible for a fly to be woken up during sleep.

The findings of this study have led researchers to question if our brain balances periods of rest and attention according to the same principle as flies. Human sleep is also characterized by slow waves, leading to intriguing parallels. The thalamus in the human brain, which is involved in filtering stimulus information and shaping oscillatory activity, suggests possible similarities with the processes in the fly brain.

While the study reveals promising insights, further investigations are required to prove if the processes in the fly brain reflect a universal principle of sleep. The research team emphasizes that their findings might reveal a universal principle of sleep, but more research is necessary to make conclusive statements.

In conclusion, the study sheds light on the fascinating neurology of sleep in flies and opens up exciting possibilities for understanding the universal principles of sleep in various species, including humans.