Homework answers / question archive / Chapter 8: Rest “Others inspire us, information feeds us, practice improves our performance, but we need quiet time to figure things out, to emerge with new discoveries, to unearth original answers

Chapter 8: Rest “Others inspire us, information feeds us, practice improves our performance, but we need quiet time to figure things out, to emerge with new discoveries, to unearth original answers

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Chapter 8: Rest “Others inspire us, information feeds us, practice improves our performance, but we need quiet time to figure things out, to emerge with new discoveries, to unearth original answers.” Ester Bucholz Physiology of Sleep We spend 1/3 of our lives unconscious— however do we really need to spend this much time sleeping? Human beings are wired to produce; it seems there simply aren’t enough hours to accomplish all that we need to do. If something has to give, it's the "nonproductive" time we are resting. You’ve just completed your sleep IQ quiz—let’s delve in to some of the research on sleep and see if you are helping or hindering your health with your sleep habits. Hormones: Three studies, conducted by Karine Spiegel and colleagues at the University of Chicago, and three sets of conclusions: Study #1: 11 healthy young men were allowed just four hours of sleep a night. After five nights of restricted sleep, the mens' ability to clear glucose from the blood (what the hormone insulin manages) was reduced by 40%. Study #2: Ghrelin is an appetite-stimulating hormone. After limiting the amount of sleep of 12 men for two nights, researchers found that the hormone ghrelin had increased by 28%. In this same study, the hormone leptin, which inhibits hunger by signaling the brain there is no need to eat, decreased by 18%. This research confirms that these sleep deprived men reported an average 23% increase in their hunger levels. Increased hunger equates to increased weight gain. Study #3: With this research, children ages 6-9, getting less than 10 hours of sleep, are 1 1/2 to 2 1/2 times more likely to be obese; adults getting less than 6 hours of sleep suggest a 50% increase in obesity. Additionally, research connects sleep restriction with type 2 diabetes (Scientific American, 2017) Think of the last time you were fatigued, running on fumes. Did you rush to the kitchen to steam some vegetables? Or grab a caffeine laced drink and some quick carbs. The latter is our default. The research is overwhelming, fatigue fuels weight gain. Question #1. True or False HomeworkUnanswered Lack of sleep makes the body less sensitive to the hormone insulin, which increases the risk of developing obesity Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a True b False Unanswered Please select an answer to submit Submit Please select an answer to submit Steeping some tea... Research has classified sleep into two general phases: non-rapid eye movement (NREM) and rapid eye movement (REM) NREM is the deeper sleep, where your muscles relax and you get the most physical restoration. Your heart rate and respiration slows and body temperature drops. This makes up about 75% of your sleep. REM sleep is more active sleep, lasting from 1-20 minutes. Your heart rate increases, breathing becomes irregular, eyes move rapidly, This is where your dreaming occurs. Have you ever felt like you were trying to fight or flee something but your body wouldn’t move? In REM sleep your muscles become paralyzed which makes sense, you can’t act out the scenes you’re dreaming! Jessica Payne, neuroscientist at Notre Dame University explains most REM sleep occurs during the last four hours of slumber. NREM followed by REM is one complete sleep cycle, usually taking about 90 minutes. If you have a Fitbit or Apple watch you can track this for yourself. This sequence is completed several times a night, depending on how much you sleep. Question #3 HomeworkUnanswered Dreams occur when? Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a Non REM sleep b REM sleep c Listening to a boring lecture Unanswered Please select an answer to submit Submit Please select an answer to submit Sleep needs: Before the age of 20 our sleep needs vary, from 16-18 hours (broken up throughout the day) for a newborn, to 9-10 hours for adolescents. How much sleep do you need? Just about all research corroborates that adults need a constant 7-9 hours of sleep opportunity each night, every night, without running a debt during the week, and paying it off by binge sleeping on the weekend. Sleep continuity is just as crucial as sleep amount. Who doesn’t need more brain power? Sleep as a memory aid: If the effect of sleep on our immune system and hormones isn’t striking enough, let’s look at the research connecting sleep to our memories. Matthew Walker, researcher at UC Berkeley and author of How We Sleep, explains how sleep prepares your brain for making new memories, and after learning, cements those memories to prevent forgetting. A region of your brain called the hippocampus, acts as a reservoir for all your short term memory. True to its name, short term memory has a storage capacity limit not unlike a USB memory stick. Each stage of sleep, light NREM sleep, deep NREM sleep and REM sleep offer different brain benefits and are critical to prevent brain impairment. Walker maintains that minimally, 7-8 hours of sleep enables this file transfer of short term memories to a a more permanent long term storage in the cerebral cortex, enabling us to wake up with a refreshed ability to learn. Winston Churchill as Prime Minister of England, had the weight of the world on his shoulders, saving England from German invasion during World War 2—Even so, he’s famously known for taking a daily nap. From Churchill: “You must sleep some time between lunch and dinner, and no half-way measures. Take off your clothes and get into bed. That’s what I always do. Don’t think you will be doing less work because you sleep during the day. That’s a foolish notion held by people who have no imagination.” Nap Study: Walker tested this research with daytime naps. A group of healthy young adults were randomly divided into nap and no nap groups. Both groups underwent a challenging learning session (100 face-name pairs) , designed to tax the hippocampus (short term memory site). Both groups performed at comparable levels. The nap group took a 90 min rest in the sleep lab, with electrodes measuring their sleep. The no-nap group stayed awake with menial activities like playing board games or perusing the internet. Later that day, both groups were challenged again with cramming yet another new set of facts into their short term storage (another 100 face-name pairs) Walker's findings were clear: the learning capacity of the brain declined with continued time awake across the day, and the effect of sleep, reversed the saturation effect and restored learning. The difference between the two groups after the 2nd learning challenge was a 20% learning advantage for those who slept. The electrical brainwaves of those in the nap group produced bursts of electrical activity called sleep spindles. These sleep spindles don’t determine the brains innate ability to learn, but rather the brains ability to replenish its learning. Walker goes on to posit that the same study was conducted after a full night of sleep replicating the same finding: the more sleep spindles that your brain generates at night, the greater your brains ability to restore itself and access that learning the next morning. Steeping some tea... The studies we’ve reviewed make a strong case for the startling effect of sleep on the brain’s ability to store information and cement that information. Does this benefit only apply to learning and amassing more facts? What about skill memory? Your ability to learn an athletic sport like ju jitsu, or swimming, or tackle a musical instrument, or learn to drive a tractor or fly a plane, —these can only be learned by doing, not by reading. You’ve heard the expression “muscle memory”, but actually it’s the brain enervating the muscle. Training and strengthening the muscles will help you execute a skilled routine, but the routine itself, the memory program, resides within your brain (Walker, 2020) . Walker tackled this concept of “practice make perfect”. Two control groups learned a lefthanded sequence on a piano—one group was tested later that evening, 12 hours later, and the other group had the same 12 hour delay, but it included 8 hours of sleep. By now you can guess what the results confirmed: Those who returned to practice the same day after 12 hours did not show any significant improvement, however those who were tested after the same 12 hour delay, but included 8 hours of sleep, showed a remarkable 20% jump in performance speed, and a 35% improvement in accuracy. Again the data is clear, your brain will continue to improve skill memories in the absence of practice, that includes a full night of sleep. Why wouldn’t we give our body this ability to repair, restore and reinforce this memory in our muscles, or in the case of a musician, in our hands? Steeping some tea... Twelve Tips for Healthy Sleep 1) Establish a consistent sleep schedule—Go to bed and wake up at the same time— make this a habit! Binge sleeping on weekends only makes Monday morning that much harder to adjust to. Set an alarm for bedtime. 2) Get regular exercise, but not within 2-3 hours of going to bed, whereupon exercise acts as a stimulant. 3) Avoid stimulants like caffeine and nicotine in the late afternoon and evening. Nicotine causes smokers to sleep lightly, or wake up early due to withdrawal. 4) Avoid alcoholic drinks before bed, as they rob you of REM sleep, may contribute to impaired breathing and can cause yo to wake up in the middle of the night when the alcohol has warn off 5) Avoid large meals and beverages late at night, which can cause indigestion or the need to wake up and urinate. 6) Avoid medicines that delay or disrupt your sleep, like asthma, allergy or even herbal cold or cough meds. Ask your health care provide if they can be taken at other times. 7) Don’t take naps after 3 pm, which can make it harder to fall asleep at night. 8). Relax before bed—Don’t over schedule your day. Have time to unwind with a bed time ritual like reading, listening to music or a hot bath can help you slow down, relax. A drop in body temperature after a bath may help you feel sleepy. 9) Take a hot bath before bed. A drop in body temperature after a bath may help you feel sleepy. 10) Dark bedroom, cool bedroom, gadget free bedroom. Get rid of anything in your bedroom that might distract you from sleep, such as noises, bright lights, from a cell phone, TV or computer. Having a comfortable bed and pillow is essential and a cool room temp makes sleep easier. If you tend to have insomnia, turn the clock away from you so you don’t worry about the time. 11) Have the right sunlight exposure. Daylight is key for regulating sleep patterns. Get outside in natural sunlight for at least 30 minutes each day. If possible wake up with the sun or use very bright lights in the morning. Sleep experts recommend that if you have problems falling asleep, you get an hour of exposure to morning sunlight and turn down the lights before bedtime. 12) Don’t lie in bed awake: If you’re still awake after 20 minutes or starting to feel anxious or worried, get up and do some relaxing activity until you feel sleepy. The anxiety of not falling asleep can make it harder to fall asleep. Adapted from Mark Walker, How We Sleep, 2017