As soon as I arrived in Finland (I have just one month left ;( ), I started being interested in understanding the sleeping mechanism.
Why do we sleep?
As far as there is not a unique answer to this question, many are contained in the functions that sleep fulfil.
Simply, after sleeping we feel usually better, and with more energy.
For Maiken Nedergaard, who led an important study at the University of Rochester while we sleep toxic proteins and molecular detritus are cleaned from the brain. To explain why this process is not possible during daytime Nedergaard says: “You can think of it like having a house party. You can either entertain the guests or clean up the house, but you can’t really do both at the same time“.
Sleep is a way to restore what the body lose while we are awake. Many functions, like the synthesis and release of the growth hormone, tissue repair and muscle growth take place mostly during the sleeping phase.
Sleep is especially important for young children whom spend most of the days sleeping and this plays a critical role in brain development. In this case sleep is correlated with changes in the structure of the brain and this phenomenon is known as brain plasticity.
Sleep is a function that all mammals (but also birds, fish, reptile, amphibious and also some simpler animals) absolve, even if in different ways. For example giraffes need to sleep about 4 hours a day while bats sleep for about 20 hours a day. This is one of the reasons why Giraffes live 25 five years in average while bats can live up to 30 years.
Dolphins and whales sleep with just half of a brain a time. Do you know why? Dolphins and whales are both mammals, and living in the water without gills obliged them to be conscious breather (they have to decide when to breath). Anyway their brain need to rest like the one of all other mammals. But sleeping in a state of unconscious would be a to high danger for survival. Resting with just half of the brain at time, is a way trough which the animal is never completely unconscious, while it can take the rest that it needs. (fount)
The inactive states of sleeping keep animals (man included in the past) out of dangerous situations and make them saving energies and resources (energy metabolism is reduced during sleep). As Jerome Siegel, neuroscientist at the University of California says “Like a maple tree dropping its leaves or a bear settling in for a winter hibernation, sleep is just another way of making sure organisms spend their resources wisely”
Sleep is also related with mythology. Vampires where habits to have a contro-natural sleeping habit. In the greek mythology Hipsnos was the god of Sleep. Son of Erebus, deity of Darkness, and Nyx, the deity of the night, he was so powerful that he was able to make sleep even Zeus, the most powerful of all the Greeks gods.
Thanks for reading.
See you at the next post,