Researchers from UT Southwestern Medical Center claim that the quality of wakefulness in mammals may affect the quality of their sleep too, by identifying two new proteins associated with alertness and wake-sleep balance.
Principal author of the study, a professor of molecular genetics and a Howard Hughes Medical Institute investigator Dr Masashi Yanagisawa, along with co-author Dr Robert Greene, a professor of psychiatry at the UT Southwestern Medical Center claim that this study, in particular, may be unique in demonstrating how sleep homeostasis could be distinguished from wakefulness- both behaviorally and biochemically. This may imply that both these processes can now be identified and studied individually.
"This study supports the idea that subjective sleepiness is influenced by the quality of experiences right before bedtime. Are you reluctantly awake or excited to be awake?" Dr Yanagisawa said.
Focusing more attention on improving hours before bedtime would play a good role in preventing sleep disorders, since it is these hours that have a profound effect on the individuals sleep, they further explain.
The study took in three groups of mice having similar genes and involved careful observation of the control groups and the two test groups- both having the same amount of sleep delay, but different exposures (one group kept awake by constantly moving them into different cages, and the other group by making light tapping movements when the mice tried to fall asleep) during their wake period.
Brain wave analysis of mice from both the test groups indicated that all the mice required equal amounts of sleep yet; the mice exposed to cage changing conditions took longer to fall asleep.
"The need to sleep is as high in the cage-changing group as in the gentle-handling group, but the cage-changers didn't feel sleepy at all. Their time to fall asleep was nearly the same as the free-sleeping, well-rested control group," Dr Yanagisawa explained.
This study, funded by the Japan Society for the Promotion of Science, if taken further, may open up new ways to assess and treat various sleep disorders, the researchers claim.
The findings of this study are now available online in the Proceedings of the National Academy of Sciences.
