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Wasted days and wasted nights
Published in James Kennaway, Rina Knoeff, Lifestyle and Medicine in the Enlightenment, 2020
Yet, such simple metaphors have enduring appeal. Matthew Walker, in describing the neuroscience of sleep deprivation, compares the rising level of adenosine in the brain to “rising water in a plugged sink when a faucet has been on” (2017, p. 34). When we at last fall asleep, the drain opens. Dean Buonomano, a professor of neurobiology and psychology at UCLA, compares the “circadian clock” that controls our sleep patterns to a water tank on a toilet with a tiny leak: the float slowly descends until it triggers the valve to fill again. “The circadian clock,” Buonomano writes, “is, of course, way more complicated than your toilet, but the idea is the same” (2017, p. 46). The same idea, I suppose, if one thinks at a level of generality so high as to be nearly meaningless. Buonomano concludes:Like the clockmakers of the eighteenth century who struggled with the effects of temperature on pendulum and mechanical clocks, evolution had to overcome the problem that the speed of biomechanical reactions changes with temperature. We still do not fully understand how ectothermic organisms … maintain a period of approximately 24 hours over daily and seasonal temperature fluctuations. But we know that there are a lot of additional proteins and genes that interact with the basic molecular machinery … and some of these bells and whistles likely contribute to temperature compensation.(Buonomano, 2017, p. 47)
Recovery from Sleep Deprivation
Published in Clete A. Kushida, Sleep Deprivation, 2004
Thomas S. Kilduff, Clete A. Kushida, Akira Terao
The expression of the immediate early gene (IEG) c-fos has been extensively used as a functional marker of brain activity in neuroscience including sleep research (53–55). In most cell types, the basal level of c-fos expression is relatively low; however, c-fos messenger ribonucleic acid (mRNA) and Fos protein can be rapidly and transiently induced by a diverse range of extracellular stimuli. Several laboratories have found that both c-Fos protein and mRNA levels decrease in the cerebral cortex during sleep relative to wakefulness (56–59). This decline has been linked to a reduction in the firing rate of the locus ceruleus during sleep and the consequent reduction of norepinephrine release in the cortex (60).
Dreaming
Published in Issues in Mental Health Nursing, 2018
A current mainstream hypothesis in cognitive neuroscience credits sleep and dreaming with a role in memory consolidation which argues that dreams are a part of the brain's consolidation of working memories into long-term memories. The neurophysiological mechanisms that we employ while dreaming (and recalling dreams) are the same as when we construct and retrieve memories while we are awake. Researchers theorize that certain memory processes can happen only when we are asleep, and our dreams are a signal that these processes are taking place (Masten, 2013; van der Linden, 2011; Ruby, 2011).