Breakthrough study reveals why we sleep

The average human spends 26 years of their lives sleeping. That’s a lot of z’s, and for what? Interestingly, the question of why we sleep is one of the great mysteries of biology.

Most theorists believe that sleep is of particular importance to the health of our brains or nervous system. After all, the effects of sleep deprivation usually take a mental toll, often in the form of memory loss, hallucinations or even seizures. Interestingly, though, every animal ever studied needs to sleep in some capacity, regardless of the size of its brain or the complexity of its nervous system.

So what gives? Well, a breakthrough new brain study might finally offer an answer. The research, spearheaded by Giulio Tononi of the University of Wisconsin-Madison, represents the best evidence yet of what happens when we sleep, reports New Scientist.

Tononi’s team took slices from the brains of mice before and after sleep. They found that synapses, or connections between neurons, were 18 percent smaller when sampled after a period of sleep. In other words, it seems that the connections between neurons in our brains are being trimmed or weakened while we snooze.

It may seem anti-intuitive to think about sleep as a good thing when it’s shrinking your brain, but it turns out that a slimmer brain has more room the following day to make new memories. At least, that’s the theory. Sleep keeps the mind open to new experiences, and to building memories of those experiences.

“Sleep is the price we pay for learning,” explained Tononi.

The theory is not only corroborated by this study, but it also explains why we find it harder to concentrate and learn new information when we miss a night’s sleep. It’s because the brain has reached its capacity, so to speak; it needs to be pruned.

Previous findings are also consistent with this theory. For instance, EEG recordings have shown that the human brain is less electrically responsive at the start of the day than at the end, suggesting that the connections may be weaker.

If Tononi’s study makes you frightened to sleep, for fear of having your experiences trimmed off, not to worry. The research also found that some synapses were protected from the trimming process, always remaining robust. These areas are probably where the most important memories are being stored, the most essential bits of information.

“You keep what matters,” reassured Tononi.

Though naturally, that leaves open the question of what matters, and how the brain determines what matters. But that’s a mystery for another day.

credit: Bryan Nelson

Why lack of sleep gives you the munchies

Looking for a better way to lose weight? Maybe it’s time to stop counting calories and start counting sheep. A new study has found a link between poor sleep and the marijuana-like “munchie” cravings that may be causing Americans to pack on the pounds.

The study, published recently in the journal Sleep, was a small but intense experiment that carefully controlled the sleep and diet of 14 20-somethings who agreed to spend several days at the University of Chicago’s sleep lab. On some nights, participants were allowed to sleep for 8.5 hours, while on others they were only allowed to snooze for 4.5 hours. Each day, the participants were given a large meal at 3 p.m. and allowed to snack from then until their next meal at 7 p.m.

Researchers found that all of the participants binged at that afternoon meal, consuming roughly 90 percent of their caloric needs at one sitting. But it was the participants who were deprived of sleep who continued to snack right up until their next meal, consuming as many as 1,000 additional calories, primarily from low-nutrient, high-reward foods (i.e. junk food.)

Blood tests revealed that the sleep-deprived participants had higher levels of a chemical called endocannabinoid 2-arachidonoylglycerol (2-AG) in their bloodstream than those who got a full night’s sleep. 2-AG is a chemical made in the brain that resembles chemicals found in marijuana. It affects pain, pleasure and appetite and has been linked to the “munchies” that pot smokers report feeling after getting high.

Typically, blood levels of 2-AG bottom out overnight but slowly build throughout the day before peaking in the late afternoon and early evening. For the sleep-deprived volunteers, 2-AG levels rose higher than they did for their well-rested peers and stayed high through the evening. This is the same period in which sleep-restricted participants noted feeling hungrier and having a stronger desire to eat. When given snacks at this time, they ate nearly twice as much fat as when they had slept for eight hours.

According to the Centers for Disease Control and Prevention, about one-third of Americans are sleep deprived, defined as getting less than seven hours of sleep each night. Guess how many Americans are also considered obese? One-third.

Coincidence? Maybe not.

Of course, diet and exercise are critical components for maintaining a healthy weight. But as this research points out, a good night’s sleep may play an even bigger role in the weight loss equation than previously thought.

Bottom line: If you’re trying to lose weight, get to bed at a reasonable hour. You’ll be more likely to resist that late afternoon junk food binge if you’re not fighting the sleep-deprivation munchies.

Credit: Jenn Savedge

Maybe we don’t need so much sleep after all

The only thing more worrisome than our lack of sleep is how stressed out we are by our lack of sleep. According to the Centers for Disease Control and Prevention, insufficient sleep is a public health problem. The agency goes so far as to link lack of sleep to health issues such as obesity, high blood pressure, depression and diabetes and even “motor vehicle crashes, industrial disasters, and medical and other occupational errors.”

It’s no wonder we’re worried about not sleeping the recommended eight hours each night. But a new study has found that maybe we don’t really need as much sleep as we thought.

The modern theory on sleep deprivation is that healthy amounts of sleep went down the toilet along with the invention of the lightbulb. Once artificial light came along, people no longer listened to natural cues about when it was time for bed. Today’s explosion of electronic gadgets and round-the-clock work schedules has exacerbated the problem.

But a new study published in the journal Current Biology took a look at the sleep patterns of three communities that serve as good examples of what life was like in the developed world before lights and distractions. Researchers evaluated the sleep habits of people in three tribes — the Hadza and San tribes in Africa, and the Tsimané people in South America — that currently live without electricity or any other modern electronic innovations that have been linked to poor sleep. And guess what? They sleep even fewer hours each night than most Americans, yet they don’t suffer from any issues of obesity, diabetes or occupational errors.

Researchers found that the people in these hunter-gatherer communities were relatively fit and healthy. Even without lightbulbs to keep them awake, they stayed up three to four hours past sunset often with only a small community fire to provide light and warmth. On most days they rise at least an hour before the sun. On average, the members of these tribes sleep for about six and a half hours each night — less than the average American.

Perhaps most importantly, the members of these tribes were not stressed about sleep. Despite sleeping less than the amount recommended by the American Academy of Sleep Medicine, they did not worry about their lack of sleep. And while chronic insomnia affects 20 percent to 30 percent of Americans, only 2 percent of the hunter-gatherers had trouble sleeping. The San and the Tsimané did not even have words for sleep problems in their languages.

The takeaway from the study is that we should all quit worrying about the numbers and focus on getting the amount of sleep we need to wake up feeling refreshed.

credit: Jenn Savedge

6 relaxation techniques for better sleep

Even if you sleep like a baby most nights, you’ve probably had at least the occasional bout of insomnia. Whether it’s that late-night snack that keeps the sandman away, stress or something less sinister, here are six relaxation techniques to try when sleep eludes you:

1. Guided visualization

Lie in bed and tell your body to relax from head to toe, suggests Joshua Jacobi, MD, an interventional cardiologist in Pasadena, California. “Forehead relax, eyes relax, cheeks relax,” and so forth down until your toes. “Then, I picture lying on a beach. I bring in all the sensory awareness to the setting. So I feel the sand in my toes, the warmth of the sun, a cool breeze. I see the waves slowly coming in to the shore. I see palm trees waving in the wind. I hear the sound of the waves as they come in,” says Jacobi. Picture this scene or something else that is relaxing for you.

2. Analyze your sleep cycle

Take a page from the Quantified Self movement and start recording your sleep data, says Ari Meisel, founder of Less Doing More Living, a productivity hack blog for optimizing, automating and outsourcing everything in your personal and professional life from fitness to email management.

His favorite sleep tracker is Basis Band, which includes sensors for constant heart rate monitoring, skin temperature, and even perspiration so you can get an incredible level of insight into the way you move through your various sleep cycles (light sleep, deep sleep, REM). “While your perceived level of exhaustion may have you convinced you are getting no sleep at all, a pattern most likely will emerge,” says Meisel. Once you identify that pattern, exploit it. “Simply knowing that you average three-hour stints instead of the 15 minutes you thought you were getting can be a huge psychological windfall.”

3. Treat your anxiety

CureCrowd, the first search engine to visually rate treatments and remedies for medical conditions by crowdsourcing the experiences of real but anonymous patients, found that users rated marijuana more highly than Ambien to treat anxiety and sleeplessness. Other remedies included exercise, yoga and prescription antidepressant/antianxiety meds.

4. Alternate Nostril Breathing

Alternate Nostril Breathing encourages deep relaxation by balancing the left and right sides of the brain while calming the nervous system, says Amita Patel, founder of Aligned Holistics, a coaching services company that combines nutrition, physical activity, relationships, career and personal philosophy.

Here’s how: Rest your right ring finger and thumb on either side of your nostrils, lightly touching them. Take a big breath in and a big breath out, then close off the right nostril with your thumb and inhale through the left nostril for a four count. At the top of that breath, close off the left nostril with your ring finger, hold and retain for a count of four, and then release the right nostril and exhale for four. Repeat as many cycles as comfortable until relaxed ending with the left nostril, recommends Patel.

5. Count backward

While lying in bed, start counting backwards from 100. Do it slowly, about once a second, 100…99…98. Take your time. “The trick is this: If you get lost or forget what number you’re on, you need to start over again from 100. Every time you get lost, gently start over. Don’t allow yourself to become frustrated, just be gentle with yourself and start back over from 100,” says Phillip Mandel, a hypnotherapist in Beaverton, Oregon. Why does it work? It’s both monotonous and mildly hypnotic. “Note that it’s not hypnosis in the usual sense, such as ‘you are getting sleepy’. Rather, you’re just doing something monotonous with your mind that will have the effect of making you sleepy,” says Mandel.

6. Guided imagery

“Guided imagery, a close cousin of meditation and hypnosis, can shift brain wave activity, and specific images can be learned that promote the brain’s movement toward deep, restful sleep,” says Leslie Davenport, a psychotherapist and author of “Healing and Transformation through Self-Guided Imagery.”

To try it, imagine a small ball of yarn. See this ball of yarn as holding the last bit of residual tension you have. Find the tip of the yarn and watch as the ball begins to roll slowly, unwinding as it moves. See the strand of yarn unfurling and resting on the floor, becoming longer as it continues to roll slowly. “Sense the decompressing. Feel the spaciousness around it now,” says Davenport. “As you watch the yarn, feel also the unwinding of any residual tension within you. Like tiny muscle fibers softening, watch as the ball continues to release from its very core, the soft yarn now stretched out, open, and completely at rest.”

Of course, this list is just a sampling. Other relaxation techniques include Progressive Muscle Relaxation, which involves tensing and relaxing each major muscle group to create awareness of tension and relaxation; somatic exercise, in which gentle, soft stretching and movements are done while lying on a mat to help shift your central nervous system to create new muscular habits that alleviate pain and tightness. And finally pandiculation, a brain reflex action pattern similar to how a dog gets up from rest, putting his front paws out and lengthening his back as he relaxes his belly. Pandiculation can wake up the muscular system at the brain level and provide deep relaxation. One or more of these may help you find that elusive 40 winks.

credit:JenniferNelson source:mnn.com