Chronobiology

Researchers Uncover the Intricate Relationship Between Sleep and Memory

Many neurological processes, such as remembering to breathe without even thinking about it, are well-understood. However, there are a few areas where modern science is just beginning to discover the truth. Sleep and memory are two such areas. We know a lot about the basics of these two important activities, but there are a myriad of details that we do not totally understand. New research suggests that there may be a link between these two mysteries of the brain.

How Do We Form Memories?

On the surface, memory seems like a simple process. Humans remember vast numbers of details, from their children’s names to how to scramble an egg. However, there is a complex mechanism underlying the simple task of remembering. The first step is memory acquisition, in which we transform our perceptions into a set of sensations that can be sent to the brain. This occurs mainly in the hippocampus of our brains and places each memory in short-term memory. If we encounter the same information again and again, the memory then undergoes consolidation, during which it gets stored in our long-term memory. In consolidation, the memory is moved from the hippocampus to the prefrontal lobe. The final stage is recall, in which we pull up the memory as needed.

Not only are there different stages involved in forming a memory, but there are different types of memory as well. These memories are each stored in different ways and processed at different times. For example, declarative memory is the memory of “just the facts” and is processed in the REM and slow-wave phases of sleep. This is the type of memory that allows you to remember your address. Procedural memory is the memory of how to do something, such as how to get from your job to your home. This also is processed in REM and slow-wave sleep, although it appears to be processed at different times during these sleep phases. Because sleep is important when it comes to processing these two different types of memory, it makes sense that sleep and memory are somehow linked.

A Link Between Sleep and Memory

There have been several studies indicating a link between sleep and memory. One experiment looked at memory recall after taking a nap. People who had more REM sleep and higher levels of change in autonomic activity had better recall of a video they had seen earlier in the day. Interestingly, the change in autonomic activity such as heart rate seemed to predict memory abilities better than the amount of REM sleep.

While the waking brain is optimized to collect information, our sleeping brains appear to be best at processing and storing it. So how does lack of sleep, a condition suffered by millions in the United States alone, affect your memory?

Can Sleep Deprivation Affect Memory?

Unsurprisingly, losing sleep either from a busy lifestyle or a sleep disorder can affect your memory intensely. This appears to be due to a resulting lack of memory consolidation, the process of moving items from short-term to long-term memory. If you seem to have to look up the same information over and over or cannot remember a coworker’s name despite seeing them regularly, memory consolidation (and by extension a lack of sleep) may be the issue.

People who miss out on sleep fail to make new memories but also fail to recall old ones. Research has found that sleep can affect the function of the prefrontal lobe, and people who do not get enough sleep on a regular basis have been found to have changes in prefrontal lobe. Coincidentally, or not, these people also experience a dip in memories and begin suffering from the memory loss seen in dementia. Your sleep may be one of the most important factors in how easily you remember the details and facts that make up your memories and knowledge base.

Are you getting enough sleep? If you are like many people in the Western world, the answer is an emphatic no. However, you may not have realized that this may be causing a variety of mental and physical health issues. Getting enough sleep, both in quality and quantity, is not only essential to healthy cognitive function and memory, it’s crucial to leading a healthy and happy life.

The Effects of Office Lighting on Productivity, Sleep and Your Circadian Rhythm

Aug 19 by Ewcopywriting Leave a Comment

There was a time when people lived by the rising and setting of the sun. Now, many people in the West live by the alarm clock and the punch of a time card. Between punches, we are left beneath the glow of artificial office lighting. While we all long for that corner office, many are left in the central cubicle. Why do we all covet the office with huge windows? More importantly, what effect does exposure to constant bright artificial office light have on our circadian rhythm?

Sunlight vs. Office Lighting

Humans evolved under the light of the sun by day—and the lack thereof at night. It is deeply ingrained in us to be active while the sun shines and then to settle down to sleep when dusk hits. However, now the lines have blurred. For most of us, the cold glare of fluorescent lights dominates our lives. Not only are we trapped under bright lights all day, but we are chained to smartphones and other devices that emit artificial light as well.

How does this affect human health? According to a new study, the effects may be subtle and insidious. Researchers set out to study people who were exposed to natural light compared with those who spent their days under artificial lights. In a nutshell, it was found that people who have little exposure to natural light throughout the day have a lower quality of life in general.

How do we know that these cubicle workers have a lower quality of life? Researchers studied groups who worked in offices lit by windows and compared them to those who work in areas without windows. People who live without natural light rate their sleep quality and even their quality of life lower. There is a good reason people fight for that corner office; it improves their physical and mental health.

The Grim Reality of Office Lighting

In nature, light changes in tone and color throughout the day. This change in color is registered by your brain and used as information to guide your circadian rhythm. On the other hand, artificial light remains the same all day. This may affect our circadian rhythms in ways we previously did not know. Your body has a harder time sensing whether it should be preparing to be alert or preparing for a nap. While constant artificial light can have an adverse effect on your health, there are ways you can mitigate the effects of working in a cubicle. Experts recommend that people with low exposure to daytime light make an effort to get outdoors, sit near a window and otherwise expose themselves to the healthy benefits of natural sunlight.

Is a Daytime Nap the Answer?

For many cubicle workers, early afternoon comes with a decrease in energy and alertness. Taking a short nap could increase your productivity in ways we previously did not realize. The circadian rhythm takes a short dip in the afternoon, an effect that is more noticeable in people without natural light exposure. Taking a nap when the urge strikes you could increase alertness and creativity in the hours before you clock out.

In fact, some of the world’s most productive employers encourage taking naps when the urge strikes. With over a third of American workers not getting enough sleep, even a short nap can make work more productive and more bearable. In fact, there is a coordinated effort to make nap time part of the American workplace due to the pervasive sleep deprivation that can make it difficult to be productive during this dip in the circadian rhythm.

Old Bodies in a New World

While we now live under bright lights, this is not how we evolved. If you are looking for ways to be more productive in your day, it might be time to get in touch with your evolved self. Find ways to be more active. Seek light during the day and darkness at night. In short, try to live as our ancestors did as much as possible. These simple lifestyle changes often allow us to walk the fine line between the demands of our biology and the demands of modern life.

Many people live without natural light in their days. However, there are ways to mitigate the damage to your circadian rhythm. By seeking sunlight wherever possible and taking naps when needed you will likely be able to walk the line.

Artificial Light Could Be Making You Sick

Aug 17 by Ewcopywriting Leave a Comment

Life on earth evolved in the presence of light. We depend on the sun to provide energy for the plants we eat, to warm our planet to a safe temperature and to regulate our sleep-wake cycles. However, most life also requires a similar ratio of dark. Humans in ancient times sought the shade at midday and enjoyed long hours of dark at night. However, times have has changed. We now live in a world of perpetual artificial light, which is not just constantly present but also a different wavelength than natural light. New research suggests that this may be harming our health in more ways than previously realized.

The Dangers of Artificial Light

Artificial light does not produce the same frequencies of light as light from the sun. It is usually brighter, a higher color temperature and higher intensity than light found in our natural environment. How does this affect our health? According to researchers, it can have a huge effect on the circadian rhythm. Our retinas sense light and pass signals to the suprachiasmatic nucleus (SCN) of the hypothalamus, which in turn regulates our circadian rhythm and a variety of biochemical and cellular processes.

The effects of disrupting the circadian rhythm extend far beyond sleep. People who have a disrupted circadian rhythm from artificial light suffer from an increase in a variety of health risks including inflammation, immune overreaction and even bone and muscle loss. An out-of-sync circadian rhythm can also cause dermatological disorders and autoimmune disease.

Light and Aging

While constant artificial light has long been known to affect health in a variety of ways, new research suggests that it may affect us in a much more visible way as well. Artificial light appears to accelerate aging, both externally and internally. Animal studies suggest that not only may people exposed to high levels of man-made light develop fine lines and wrinkles more quickly, they may also have accelerated aging of their bones, muscles and organs. In studies, the mice exposed to artificial light 24 hours a day aged much more quickly.

While this is bad news for many modern people, there is good news as well. The mice in the studies partially recovered from the effects of the accelerated aging within two weeks of being returned to a normal sleep-wake cycle. If you are feeling over-tired and generally older than you should feel, you may be able to improve your appearance and health by reducing light exposure and stabilizing your circadian rhythm.

Is It Possible to Escape Artificial Light?

The problem for many modern people is that reducing light exposure can be a difficult task. We have televisions and devices that can be turned off, but these are not the only contributors to an increasingly light world. Many streetlights are high color temperature LED lights, which cause a huge range of negative health effects. In fact, the American Medical Association has warned communities not to use high color temperature streetlights, although many areas continue to do so.

In addition, light pollution is a major issue in many parts of the world. Even if you turn off your own sources of artificial light, the world is simply lighter and brighter than ever before. Sometimes there is no escaping this pervasive light.

Restoring Your Own Natural Rhythm

Even if you cannot completely escape ambient light in the environment, there are a few ways that you can encourage a healthy circadian rhythm. Turn off lights in your house at night, including devices and electronics that produce light. Go to sleep and wake at roughly the same time so your body can develop a set sleep pattern. Close your curtains and blinds to keep light pollution outside. You can also take a melatonin supplement in the evening to help your body prepare for a good night of restful sleep.

Artificial light is everywhere and may present a danger to the public health. However, there are ways to reduce and compensate for the negative health effects of this light. Getting your circadian rhythm on track is the first step to living a healthier and happier life.

Nighttime Awakening: Are Two Sleeps Better Than One?

Aug 03 by Ewcopywriting Leave a Comment

Most modern people accept that the “correct” way to sleep is to go to bed at night and stay asleep until morning. In fact, waking at night and being unable to go back to sleep is often considered a sleep disorder. However, there is evidence that humans did not always consider a full night of uninterrupted sleep ideal. Choosing to engage in “two sleeps” may be a common pattern in human history—and a healthy pattern as well.

Bimodal Sleep in Human History

Bimodal, or segmented, sleep appears to have been the way that many of our ancestors slept. Ancient physicians, as well as authors such as Charles Dickens and Chaucer, refer to a first and second sleep in their writings, with the time between the two sleeps spent engaged in quiet activities. Historians believe that this habit disappeared some time around the turn of the twentieth century when electrical light became common.

Just 200 years ago, people routinely woke at night to socialize, pray, read, have sex and otherwise enjoy some quiet time. Most people stayed in bed during this time, although some got up for short periods. The practice of two sleeps appears to have been especially common among the working classes, who were too worn out to be productive immediately after arriving home from a day of manual labor. Doctors even recommended the period between the first and second sleep as the best time to conceive a child.

The Problem of Middle-of-the-Night Insomnia

The very sleep pattern that our ancestors viewed as normal is now often considered a sleep disorder. Sleep maintenance, or middle-of-the-night insomnia, is the most common type of insomnia in the United States. While this disorder can be caused by GERD, anxiety and other health disorders, many people who experience it appear to have no physical cause. Doctors recommend that people who wake at night and cannot get back to sleep do some type of sedentary activity in low light and go back to sleep when they are able, which is strikingly similar to how our ancestors once passed midnight hours.

Middle-of-the-night insomnia may be common because it is a normal human sleep pattern. Could it be that some people who believe they have a sleep disorder may in fact just need to rearrange their evening and night time schedules to allow two sleeps?

Are Two Sleeps Really Better Than One?

Researchers believe that ancient humans tended to sleep around three-and-a-half hours in each sleep cycle, with around two hours between the first and second sleep. Melatonin levels remain high throughout both sleeps and the quiet wakeful phase in between, while the sleepiness preceding the second sleep is caused by a surge in the sex hormone progesterone. Choline levels also differ in people who follow the practice of segmented sleeps. This means that the second sleep has more cholinergic REM phases, which causes more restful slumber and more lucid dreams.

For many people, it could be that middle-of-the-night insomnia is not so much a sleep disorder as a sign that they need two sleeps rather than one. That nighttime period of wakefulness may be the most creative time, while the second sleep appears to be more restful than a normal continuous seven-hour sleep.

Why Did We Start Sleeping in One Block?

If sleeping in two blocks is healthy, why did people stop? There are a few suggested reasons. First, electric light made it possible for people to stay up later at night, making it difficult to get in two full blocks of sleep plus a rest period. Second, the world began to focus more on efficiency. Suddenly, laying in bed and being relatively unproductive for several hours every night was viewed as a waste of time.

While most people have adapted to the practice of sleeping in one seven to eight-hour block, some still struggle. Sleep maintenance insomnia may merely be a return to old ways, which explains why it is so hard to treat. If you have trouble with waking in the middle of the night, it may be time to see if segmented sleep, or engaging in two sleeps, works better for your body.

Proven: Napping Boosts Productivity and Improves Mental Health

Jul 29 by Ewcopywriting Leave a Comment

Have you ever snuck a nap in the middle of the day? Modern schedules tend to favor people who are up at dawn and steadily working until sundown. Benjamin Franklin and other fathers of our nation praised those who worked tirelessly, eschewing sleep until nightfall. Our society is set up to support this behavior; jobs begin early and lunch breaks are nonexistent or too short for more than a quick bite to eat. People who sleep a bit in the early afternoon are even considered lazy by many. However, the disdain for the afternoon siesta may be counterproductive. There are several benefits of napping that we are missing out on by pushing through the day rather than pausing to get the rest we need.

The National Deficit of Sleep

Americans are not skipping their daily siesta because they get enough sleep at night. Quite the contrary; sleeplessness is reaching epidemic levels. Researchers estimate that 40 percent of adults and 70 percent of teens are sleep-deprived. The amount of sleep that we get has dropped by 20 percent in the past century. People are getting less sleep than ever in human history, which may be tied to rising rates of metabolic disease.

What can Americans do to improve our sleep, and thus national public health? Experts suggest that a good old-fashioned nap may be the answer. Not only can a nap add to your total sleep time, but it can help you be even more productive and creative once you wake.

The Proven Benefits of Napping

According to research conducted over the past decade, there are several important benefits of napping. People who nap have sharper minds and are able to solve complex cognitive tasks more quickly and correctly. Napping also reduces frustration levels and encourages good mental health. While many think of a nap as wasted time, it may actually make you more productive. After a nap, you think more creatively and work more quickly, making up for any time lost in sleep—and then some.

Can’t we just opt for an earlier bedtime? Is napping better than sleeping longer at night? The jury on this subject is still out, but evidence suggests that we are biologically primed for a short siesta. Hormones associated with alertness dip in the early afternoon, leaving many people feeling tired and duller mentally. If you are sleep-deprived, this afternoon dip in brain function has an even greater effect. This mid-day sleepiness can affect productivity immensely if people do not get the rest that they need to move on with the rest of their day.

How to Nap Like a Pro

If you are interested in making a quick nap part of your lifestyle, experts have a few suggestions for getting the most out of your sleep. First, nap at the same time every day, preferably the time when you are most prone to feeling sleepy. Be sure to limit this time so you do not get too deep into your sleep cycles to wake up quickly; experts recommend 20 to 60 minutes as the ideal nap length. Second, find a comfortable and quiet place so you can nod off quickly and get the most out of your sleep. If you plan to take only a 20-minute nap, drink a cup of coffee first. Although this may sound counterproductive, caffeine takes around this length of time to take effect so it will be kicking in right as you are waking up.

The benefits of napping are clear, so why don’t Westerners make it a national habit? If you’re suffering from an afternoon slump, taking a quick nap may be just what the scientists ordered. Even a short 20 minutes of sleep could leave you renewed, refreshed and ready to take on the rest of your day.

Meal Timing: Is When You Eat as Important as What You Eat?

Jul 27 by Ewcopywriting Leave a Comment

With obesity reaching epidemic levels in the United States and much of the Western world, many people are struggling to lose a few (or more!) extra pounds. Often those wishing to lose weight strive to eat less and to fit more activity into their lives, only to be disappointed with minimal results. As a result, weight loss is becoming a huge national industry, yet one that does not often deliver on its promises for the average person. What if another factor besides caloric intake is contributing to our ever-expanding modern waistlines?

Could When You Eat Affect Your Health?

Our ancestors ate at regularly-scheduled times and often with their family or clan. However, this is not possible for many people now. Most of us have to grab a bite when we have the chance, between work, errands and social obligations. In addition, the availability of tasty and affordable snacks makes it easy to graze our way through the day. For many people, eating throughout the day and into the night has replaced proper meals and some diet systems even claim incorrectly that this is a healthy behavior.

For from being a healthy choice, eating multiple meals throughout the day—especially after a certain time of day—appears to be disastrous for our metabolisms. In fact, a recent analysis of current research suggests that when we eat may be a major factor in weight gain or loss. Shift work has been linked to metabolic syndrome, which is believed to be due in part to eating at odd hours. People who switch to eating most of their calories early in the day see increased weight loss and better blood glucose control. While we have no definitive causal link between eating at regular hours and keeping a trimmer waist, studies certainly suggest a correlation.

The Science Behind Regular Meals

How can when you eat have such a huge effect on your weight and your health? Our bodies run on several internal clocks. Our metabolism, in particular, follows a circadian rhythm. Eating at the same times every day allows your body to plan ahead, ramping up insulin production and firing up your metabolism in anticipation of the meal ahead. If you do not eat at roughly the same times every day, your body cannot prepare itself on a hormonal level for metabolizing the calories you are about to take in.

Eating in the evening appears to be an especially poor decision for metabolic health. Glucose control is stronger in the morning than in the evening, which means that eating regularly in the evening can lead to blood sugar fluctuations. These fluctuations may contribute to metabolic syndrome and type 2 diabetes over time. This may explain why people who eat most of their calories in the morning see such an improvement in blood glucose control and their weight. Even without changing their diet, they can control how carbohydrates are used.

Can a “Chronodiet” Lead to Better Health?

Planning when you eat appears to be as important as planning what you eat. Many people find success by following a “chronodiet” that aligns meal times with their body’s internal clock. Eating most meals between 11 a.m. and 4 p.m. helps many people to lose weight even when consuming the same amount of calories. In addition, planning when you eat different kinds of food can help. For example, it is best to eat most of your carbs in the morning when insulin (and thus blood sugar control) is at its highest levels.

Humans evolved to lead a lifestyle that is very inconvenient in the modern world. As a result, many people are struggling with their weight as metabolic syndrome and related diseases continue to rise. Planning when you eat so it aligns with the best calorie-burning times of the day may help many people to lose a few pounds while leading a longer, healthier life.