One summer in college I worked in a sleep lab, and we kept four teenagers in the basement of the lab living on 28-hour days. They had to be watched, tested or entertained for three weeks straight. It might sound harsh for them, but they had fun. They got to sleep a lot, and play board games, watch movies, and learn Tai Chi. They called it Sleep Camp and got paid just as much as we did. But for those of us who worked there it was pretty rough.
In order to study sleep it often means you have to miss out on experiencing it for yourself. While most of my friends were partying late into the night, I had to wake up at 3:15 in the morning. When you have to wake up that early, there's no good time to go to sleep. Technically the right bedtime would be 7PM, but I mean come on! This was summer in New England: I had no AC and the sun didn't even set until 9:30.
It was a good lesson in practical neuroscience though. In class I had just learned about sleep hygiene and it's impact on the brain, so I was acutely aware of how I was impairing myself. Sleep hygiene is a combination of your behaviors and environment surrounding sleep. Thankfully I wasn't alone, as 40% of Americans don't do such a great job at it.
Poor sleep hygiene leads to a lack of quality sleep, which has numerous negative consequences. How do you know if you have bad sleep hygiene? Well for some people it means they have lots of trouble falling asleep at the right time; for others it means they have no difficulty falling asleep at the wrong time (e.g. a movie theater or while driving). Here's a quick one-question test: how do you feel around 2:30 in the afternoon on a weekday?
First and foremost lack of quality sleep affects your mood (i.e. makes you feel crappy). It also lowers your pain threshold, increases your blood pressure, and interferes with your memory. It harms your immune system, elevating your chances of getting sick. It diminishes your ability to concentrate, and makes you more impulsive. It can also cause weight gain. The reason why most people don't notice the negative effects of poor sleep is because they rarely get enough quality sleep. Thus they just get used to feeling that way all the time. On top of that, because the brain is impaired by poor sleep, it is impaired in its ability to judge how impaired it is, just like when you're drunk.
Here are 14 suggestions to improving your sleep hygiene and getting more quality sleep. Unfortunately, you probably won't like some of the suggestions, just like I didn't want to go to sleep at 7PM. However, even if you don't follow them, you can at least be aware of the decisions you're making, and how they're affecting you. For me at least, when I'm feeling crappy, it's much better to realize it's by choice. Also, if you know someone who has difficulty with sleep, please pass on these tips.
1. Go to bed at the same time every day. "Except the weekend right? It's ok to stay up late and sleep in, right?" I told you that you weren't going to like it. After a night of partying definitely better to get enough sleep than wake up early, but not as good as not staying up too late in the first place. The reason for going to sleep at the same time is that your brain releases melatonin about 30 minutes before it thinks you want to go to sleep. If it doesn't know when you're gonna go to sleep it can't do that. Unfortunately you can't just say to your brain, "Time to get ready for bed." It's like a small child. It needs to be trained, which requires repetition. It's ok to vary a little, and also ok to occasionally stay up late, but there should be a clear time you think of as your bedtime.
2. Avoid bright lights after the sun goes down. The melatonin that prepares you for sleep is inhibited by bright light. You don't need to walk around in the dark, but when it's getting close to bed time turn off most of the lights in your house (as an added benefit this is also cheaper and good for the environment).
3. During the day stay in a brightly lit environment. The melatonin cycle is part of a hormonal package collectively called circadian rhythms, controlled by a region of the brain known as the suprachiasmatic nucleus of the hypothalaums (not to be confused with supercalifragalisticexpialadocious), which projects to the pineal gland to release various hormones. These rhythms are synchronized by bright lights during the day. So take a few minutes to go walking in the sunshine (or on sunshine, woooah). This has the added benefit of boosting your serotonin, which may be why it helps sleep, as melatonin is derived from serotonin.
4. Sleep for 8 hours straight. Your brain needs to cycle through various stages of sleep (Stages 1 to 4 and then REM sleep). Each cycle takes about 90 minutes, so in about 8 hours you get the appropriate number of cycles. If you wake up in the middle of a cycle you don't feel rested. Your brain needs to know how much time it has to get everything done it needs to. It can adjust a little, but most people need about 8 hours. However, you need to pay attention to how much sleep you actually need. 8 hours might not be enough for you. C'est la vie. In general the older you are the less sleep you need. In college you need about 8 hours and 24 minutes (approximately). When you start drawing Social Security you might only need 7.
5. Use your bed/bedroom for sleeping, not doing work. That way your brain associates your bed only with sleep, and it will induce sleepiness like Pavlovian conditioning. N.B. It's ok to have sex there too.
6. Make your environment comfortable. Sleep requires down-regulation of the sympathetic nervous system, which is harder if you're uncomfortable. If your room is too cold, or too hot, or too noisy, or too smelly, then do something about it. If it's something you can't change, then just accept it.
7. Don't take naps. And stop rolling your eyes at me; I don't make the rules. The occasional nap is ok, but don't make them a regular part of your routine. Sleeping for 7 hours, and then taking a 1 hour nap another time, is not as good for your brain as sleeping 8 hours. Also, taking a nap will often make it difficult to fall asleep at your bedtime. This may surprise you, but if you actually consistently get quality sleep, you won't even feel the need to take a nap.
8. Create a routine for preparing for sleep. Do it every night. This helps you separate yourself from the hectic nature of the rest of your day. It prepares your brain for sleep. If you're running around taking care of everything all day, and then just plop into bed, your brain still needs to wind down, and you may have difficulty falling asleep. A bedtime ritual might be brush your teeth, wash your face, go to the bathroom, and then read for a few minutes. Or maybe you include herbal tea as part of that, or reading to your kids beforehand, or saying your prayers. These should be non-stressful activities. If you have a really hard time falling asleep, then include some meditation as part of your routine. N.B. Again, sex is ok, but probably can't be relied upon as part of your regular routine (if it can, then props to you).
9. If you find you're stressing over all the things you have to do, then write them down. Your prefrontal cortex is responsible for keeping all these things in your working memory, and worrying about forgetting them is stressful. That stress inhibits sleep. However, millions of years of evolution have led to the invention of the pen and paper (and voice recorders). Thus, you don't need to keep your prefrontal cortex working overtime.
10. Just chill. If you can't fall asleep, you can't fall asleep. No need to get upset with yourself. Just pick a comfortable position and lie there. Don't look at the clock. However long it takes you to fall asleep is how long it takes. Moving around, or worrying about it is not helpful. Sometimes also people fall asleep briefly and wake up and think that they didn't fall asleep, and get annoyed that they're not falling asleep. Just relax, and lie still in a comfortable position. If after 20 minutes or so you're still not asleep, then go to another room. Do something relaxing for a little bit, then try again.
11. Avoid caffeine near bed time. Duh.
12. Don't eat a large meal less than 3 hours before bedtime. Indigestion can interfere with sleep, and acid reflux is more common once you're horizontal.
13. Don't use alcohol as a regular sleep aid. While it may help you fall asleep, it disrupts the patterns of brain activity while you're asleep. That means your sleep is not as restful as it could be.
14. Exercise. Exercise is pretty much good for everything. Make physical activity a regular part of your life. The exact role of exercise in improving sleep though is not well understood. It may be due to increased levels of the neuropeptide orexin, which is essential for appropriate sleep regulation. It may also be due to the effects of exercise synchronizing circadian rhythms, or stress reduction, or some combination of several factors. Regardless of the reason though, it is clear that aerobic exercise helps improve sleep. Exercising too close to bedtime may make it difficult to fall asleep though, so try to do it a few hours before. N.B. Again, sex is ok.