It may be hard to believe that studies that are being done on the way that fruit flies sleep would be helpful to our understanding of why we sleep, or how to improve our sleep, but researchers have been using the diminutive bugs for years with great success. Studies conducted at Washington State University back in 2011 were published in Science magazine and revealed exactly what the switch is within the brain that tells us to go to sleep, as well as how it works, and further studies being conducted at Oxford are going even further in aiding scientists’ understanding of why all animals sleep.
The question of what sleep’s purpose is has been being studied for decades. Prior to the twentieth century the theories on sleep were that it was a sort of death or coma. Some believed that the soul travelled or was an opportunity for the gods to visit us while we slept, while others believed that sleep was caused by a lack of oxygen to the body, or by the arrival of toxins each night. Today we understand a great deal more about the impact of sleep, and yet there is much more that needs to be learned.
Dr. Jeff Donlea was an integral part of the team at Washington State University that first determined the existence of a “sleep switch” in our brains; his original work led to the understanding that molecules exist in the brain for the specific purpose of controlling sleep-promoting neurons. Now he is actively pursuing further studies about their role and how they work alongside Professor Gero Misenboeck at Oxford.
The two men have continued their work on the mechanism of those neurons in fruit flies in the belief that they act in much the same way in all animals, including humans. “There is a similar group of neurons in a region of the human brain. These neurons are also electrically active during sleep and, like the flies’ cells, are the targets of general anaesthetics that put us to sleep. It’s therefore likely that a molecular mechanism similar to the one we have discovered in flies also operates in humans,” said Donlea. The promise of determining exactly what proteins in the brain have an impact on making us fall asleep can help with the creation of new and better drugs for the treatment of insomnia and other sleep disorders.
The goal of the work being done at Oxford is to figure out exactly what it is that the sleep switches are looking for. According to Dr. Diogo Pimentel, who is also a lead author in the study, “The big question now is to figure out what internal signal the sleep switch responds to. What do these sleep-promoting cells monitor while we are awake. If we knew what happens in the brain during waking that requires sleep to reset, we might get closer to solving the mystery of why all animals need to sleep.”
The group’s studies involve subjecting fruit flies to periods of extreme sleep deprivation and examining the impact on normal flies versus those who have been genetically modified so that their sleep switches never turn on.