Long-term multichannel recordings in Drosophila flies reveal altered predictive processing during sleep compared with...

Area of Science:

• Neuroscience
• Sleep Science
• Animal Behavior

Background:

• Sleep is classically defined by decreased behavioral responsiveness to external stimuli.
• It is unclear if reduced behavioral responsiveness during sleep correlates with reduced brain activity responsiveness, particularly in insects.
• Drosophila melanogaster serves as a model organism for studying sleep.

Purpose of the Study:

• To investigate brain activity responses to visual stimuli during sleep in Drosophila melanogaster.
• To determine if the sleeping fly brain processes predictable and unpredictable stimuli differently.
• To explore the role of sleep in regulating predictive processing.

Main Methods:

• Long-term multichannel electrophysiology was performed on tethered Drosophila melanogaster.
• Flies were continuously exposed to repetitive and variable visual stimuli.
• Local field potentials (LFPs) were recorded across the fly brain, from optic lobes to the central brain.

Main Results:

• Drosophila melanogaster maintained sleep under continuous visual stimulation, based on immobility criteria.
• No significant difference in LFP responses to repetitive visual stimuli was observed between sleep and wake states.
• LFP responses to variable, low-probability visual stimuli were altered during deep sleep, particularly in the central brain.

Conclusions:

• The sleeping fly brain differentiates between repeated and low-probability visual stimuli.
• Altered processing of unpredictable stimuli during deep sleep suggests a role for sleep in predictive processing.
• Drosophila melanogaster is a valuable model for studying sleep's role in neural processing and prediction.