sleep

I’ve been working on adapting a two-process mathematical model of sleep regulation that provides a theoretical framework around which Drosophila sleep can be understood. We recently published our initial findings in SLEEP. The two-process model was first formulated and proposed in the early 1980s and has been a very useful model to explain the amount and timing of human and rodent sleep for nearly four decades. Our work helps the field of fly sleep make the same use of this powerful model and direct hypothesis driven quantitative experiments in fly sleep.

Further, this work of ours has established that long periods of immobility in the fly correspond to deeper sleep states – thereby demonstrating the power of behavioral features as an equivalent to EEG based metrics of vertebrate sleep. The two-process model is so called because it is widely believed that a circadian clock process regulates the timing of sleep and a homeostatic process regulates the amount of sleep. The homeostatic system is a critical regulator of sleep, which restores lost sleep upon deprivation. In collaboration with other colleagues, I’ve developed a new experimental method which allows us to accurately estimate the effects of sleep deprivation in the fly system that mirrors patterns of recovery sleep in humans, and we have identified serotonin as a key, conserved regulator of sleep homeostasis.

Future work is aimed at understanding the intersection of these two processes in the fly system. Stay tuned to know what we find.