Why do we Sleep?
Neuroscientist Russell Foster delivered a presentation to TEDGlobal regarding our dependency on sleep, and how we as a society don’t appreciate a good nights rest. And he asks: What do we know about sleep? Not a lot, it turns out, for something we do with one-third of our lives. In his Ted talk, Foster shares three popular theories about why we sleep, busts some myths about how much sleep we need at different ages — and hints at some bold new uses of sleep as a predictor of mental health.
He quotes Thomas Edison, “Sleep is a criminal waste of time, inherited from our cave days”, and Margaret Thatcher, “Sleep is for wimps.” In a nutshell we are inclined to resist sleep, especially in an age of the internet where distractions are rampant and our basic bodily needs can be lost in the stream of activity that surrounds us. Foster goes on to say that not only do we not appreciate sleep, but we treat it like an illness and an enemy.
Scientists have been debating the function of sleep for decades and it’s true function has never been conclusively decided upon. Although, we do know that some areas of the brain are more active during the sleep stage than while the body is awake. But the essential question is: Why do we sleep? Currently, there isn’t any real consensus, but Foster gives us three possible answers:
Sleep is for Restoration
Sleep replenishes and repairs metabolic processes. Many genes are “turned on” only during sleep — genes associated with restoration and metabolic pathways. Also, while you’re asleep you generate higher levels of neurotransmitters which help replenish your muscles in preparation of tomorrow’s activity. Restoration theories of sleep make cognitive sense since we suffer so many unpleasant consequences when deprived of sleep
Sleep is for Energy Conservation
Sleep also allows your body to save calories. The difference between sleeping and quietly resting is about 110 calories a night, the equivalent of a hot dog bun. All in all, it’s not a very good upshot for such a complex process. You’d be better off exercising or find a way to induce sleep walking.
Sleep is for Brain Processing and Memory Consolidation
Studies show that if you prevent people from sleeping after learning a task, their ability to learn is subsequently smashed. And even better, our abilities to come up with novel solutions after a complex task are reduced after sleep deprivation. Supposedly your brain is consolidating memories and images of day. The transition of complex events or images are moved from your short term memory to your long term. If you’re worried you’re forgetting things, you can always zap your brain with an electrode.
Sleep may Prevent Mental-health Problems
Foster’s true expertise shows in his new research. Foster and his colleagues are conducting experiments on the links between sleep and mental illness. According to Foster’s research, genes that have been shown to be important in the generation of sleep, when muted, predispose individuals to mental-health problems. He points out that sleep levels could be used as an early warning signals for illnesses like schizophrenia. Research has found that schizophrenia patients stay awake during the night phase, asleep during day, suggesting that sleep and mental illness are not simply associated, they are physically linked. Which opens the door for sleep to be used as a new therapeutic target.
Research against Restoration Theories
Studies have been conducted that counter restoration theories. Although none are conclusive I have outlined some key points below:
- Protein synthesis occurs 24 hours a day, not just during particular stages of sleep.
- Amount of sleep does not appear to decrease when our level of daytime activity decreases.
- Following great physical exertion the amount of additional sleep we need may only be negligible.
- The brain is very active during REM so runs counter to the idea that it is an ideal time for repair.
- When we miss out on long periods of sleep it does not seem to affect our physical well-being. A good night’s sleep and we’re back on top.
Some simple tips to help you get a good night’s sleep:
- Stick to a regular bedtime and try to get up at scheduled time. If you’re brave enough, ditch your alarm, and your body will eventually adjust and naturally wake itself up.
- Get lots of daylight, but avoid bright light before bedtime. So shut down that computer, or brush your teeth in dim lighting.
- Use your bed only for sleeping or lovemaking, never for reading or watching TV. If you can’t sleep after 15 to 20 minutes, get out of bed and go into another room. Read quietly with a dim light but don’t watch TV, since the full-spectrum light emitted by the tube has an stimulating effect.
- Avoid napping during the day. If you do, which I personally recommend but the sleep experts don’t, restrict your nap to 15 to 20 minutes in the early afternoon.
- Get plenty of exercise. Build up to 30 to 45 minutes of moderate exercise every day; sprinting or weight training is an excellent choice. Preferably try to get your exercise early in the day, and then try some stretching exercises at night to relax your muscles and your mind before bedtime.
- Eat properly. Avoid caffeine, especially after mid-afternoon. Try to avoid all beverages after dinner if you find yourself getting up at night to urinate, unless it’s water which you can never get enough of.
- Avoid alcohol after dinnertime; although many people think of it as a sedative, alcohol can actually impair the quality of sleep.
- Be sure your bedroom is dark and quiet. It should also be well ventilated and kept at a cool temperature. The darker the environment, the better.
- Above all, don’t worry about sleep. Watching the clock never helps. Don’t keep track of the amount of time you spend trying to sleep. Instead, just rest quietly and peacefully, quality over quantity.
Have you ever wanted to take control of your dreams? Now you can, with the science of how to lucid dream! With these simple steps, and a little practice, you’ll soon experience sleep like never before.
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