By Dan Brooks
Sleep is a complicated concept that continues to baffle researchers. Thankfully there are members of the scientific community that are intent on researching and understanding the fundamental mechanisms that govern sleep in organisms. The fundamentals of our understanding of sleep are limited but include evidence for sleep modulation. For example, it is generally agreed that the sleep homeostat and the circadian clock play major roles in our regular sleep cycles as well as in a process known as rebound sleep; researchers believe rebound sleep is a way for our bodies to compensate for lost sleep. The understanding that these systems are involved in the regulation of sleep duration and timing helps establish a foundation for the understanding of sleep overall.
When exposed to a female fly, the male neglected to recover sleep.
Known factors influencing sleep include excitement, caffeine consumption, pheromones, aromas, and arousal. When included in our understanding of sleep modulation we begin to see a clearer picture of the major players in our sleep cycle. Unfortunately, research does not have a robust understanding of the entire process but there are countless scientists working tirelessly to identify these fundamental concepts.
Two of these scientists are Bethany A. Stahl and Alec C. Keene who discuss several noteworthy sleep studies in flies in their publication "To rebound or not to rebound". They cite a study performed by Beckwith et al. reporting new insights into how sexual arousal in flies affects their need for sleep. Beckwith et al. examine how social sleep deprivation affects rebound sleep. They exposed male flies to a variety of environments including two scenarios, 1) with a female present before a male, and 2) with only a male. When exposed to a female fly or the leftover pheromones of a female, the subject male fly lost sleep and neglected to recover via rebound sleep. This was notably different behavior from when another male fly was introduced to the initial male, which caused loss of sleep but was compensated by rebound sleep once the second male was removed. This difference in compensatory rebound sleep piqued the interest of researchers and warrants further investigation into the role of sleep modulation and sexual arousal.
This study by Beckwith et al. contributes to a growing body of research on rebound sleep. Although flies are a distant reductionist model from humans, this study supports the role of environmental factors in sleep cues. Considering research by Beckwith et al., future research on the influence of hormones and sleep in different organisms is relevant for a better understanding of humans’ sleep cycle and rebound characteristics.
Beckwith, E. J., Geissmann, Q., French, A. S., & Gilestro, G. F. (2017). Regulation of
sleep homeostasis by sexual arousal. eLife, 6, e27445.
Stahl, B. A., & Keene, A. C. (2017). Sleep: To rebound or not to rebound. eLife, 6,