Sleep induced by mechanosensory stimulation provides cognitive and health benefits in Drosophila

Study Objectives Sleep is a complex phenomenon regulated by various factors, including sensory input. Anecdotal observations have suggested that gentle rocking helps babies fall asleep, and experimental studies have verified that rocking promotes sleep in both humans and mice. Recent studies have expanded this understanding, demonstrating that gentle vibration also induces sleep in Drosophila. Natural sleep serves multiple functions, including learning and memory, synaptic downscaling, and reduction of harmful substances associated with neurodegenerative diseases. Here, we investigated whether vibration-induced sleep (VIS) provides similar cognitive and health benefits in Drosophila. Methods We administered gentle vibration to flies that slept very little due to a forced activation of wake-promoting neurons and investigated how the vibration influenced learning and memory in the courtship conditioning paradigm. Additionally, we examined the effects of VIS on synaptic downscaling by counting synaptic varicosities of select neurons. Finally, we determined whether vibration could induce sleep in Drosophila models of Alzheimer's disease (AD) and suppress the accumulation of Amyloid beta (A beta) and Tubulin Associated Unit (TAU). Results VIS enhanced performance in a courtship conditioning paradigm and reduced the number of synaptic varicosities in select neurons. Moreover, vibration improved sleep in Drosophila models of AD, reducing A beta and TAU levels. Conclusions Mechanosensory stimulation offers a promising noninvasive avenue for enhancing sleep, potentially providing associated cognitive and health benefits.