Sta Hungry Stay Foolish

Stay Hungry. Stay Foolish.

A blog by Leon Oudejans

From wintersleep to hibernation

7 December 2015

0

I am not in the best of moods. I even know why: lack of sunlight. I already mentioned the impact of lack of sunlight on the human mood in my 9 November 2015 blog: Weather is your mood and climate is your personality. I also sleep more than usual and experience a feeling of tiredness even when awake. Partly because it’s still dark when I get up, grey during the day, and partly as it’s already dark in the late afternoon. At times the idea of having a wintersleep seems appealing. Having a wintersleep was once “normal” but electricity, heating, and artificial lights made us forget about this.

AccuWeather: The change in light can have a big effect on the time and quality of your sleep. The amount of daylight during the winter is more limited than in the other seasons, impacting the body’s cycles. Light directly impacts the pituitary gland, or hypophysis, which secretes melatonin. Melatonin regulates the body’s sleep-wake cycles. Lack of light can cause the body to produce more of the chemical, making the body feel tired and sluggish. 

NYT: “In the mountains, the tradition of seasonal sloth was ancient and pervasive. “Seven months of winter, five months of hell,” they said in the Alps. When the “hell” of unremitting toil was over, the human beings settled in with their cows and pigs. They lowered their metabolic rate to prevent hunger from exhausting supplies. The same mass dormancy was practiced in other chilly parts. In 1900, The British Medical Journal reported that peasants of the Pskov region in northwestern Russia “adopt the economical expedient” of spending one-half of the year in sleep: “At the first fall of snow the whole family gathers round the stove, lies down, ceases to wrestle with the problems of human existence, and quietly goes to sleep. Once a day every one wakes up to eat a piece of hard bread []”. 

A human wintersleep is not the same as hibernation. The zoological phenomenon known as winter sleep, or hibernation, was long viewed as the exclusive domain of bears, the dormouse, marmots and squirrels, mammals that sleep away about half the year. But new observations prove that not only mammals, but also birds are capable of shutting their metabolisms to minimal levels. (Spiegel)

Winter sleep is far more common than previously assumed, and by no means limited to winter or to mammals. A lack of food or water, and not cold temperatures, say the scientists, is usually what prompts animals to retreat into energy savings mode. Lemurs on Madagascar hibernate during the dry season, while California ground squirrels go to sleep during the heat of summer. Even deer and the primeval Przewalski’s horse can switch their metabolism to economy mode. (Spiegel)

Almost all hibernating animals go through wake-up phases, during which they consume 90 percent of stored energy reserves. These periodic cold starts continue to puzzle researchers. Do the animals need a toilet break? Do their immune systems need time to clean out the body? A different theory now seems more likely: The animals wake up to avoid brain damage. “Apparently, cooling down the brain for extended periods of time creates the risk of breakdowns,” says Gerhard Heldmaier, a physiologist at Germany’s University of Marburg, “and that’s why it has to be warmed up periodically.”(Spiegel)

The study of hibernation and its application to humans has interesting potential for medicine (eg, parallels to Alzheimer brain damage, prolonged human organ storage and hypothermic operations) and also for astronauts. NASA and the European Space Agency launched a research program into the issue some time ago. However, Heldmaier warns against undue expectations. “All of this is still basic research.” The technology, he adds, is worthless without precise knowledge of the mechanisms involved. “Naturally, memory loss would be unacceptable for a voyage to Mars.” (Spiegel)

Cold as Ice (1977) by Foreigner
artists, lyrics, video, Wiki-1, Wiki-2

Note: all markings (bold, italic, underlining) by LO unless stated otherwise.

Archives

VIPosts

0 Comments

Submit a Comment

Your email address will not be published. Required fields are marked *

Pin It on Pinterest