Mysteries of Sleep: Brain Activity and Sleep's Restorative Effects

Lab rats may provide us with new clues on the mechanisms that make sleep restorative. A study published Wednesday in the Journal of Neuroscience, the authors say, is the first to precisely measure brain energy to learn more about the biological functions of sleep.

Researchers observed a dramatic energy surge in certain parts of rats’ brains when the animals first fell asleep. While the rats were in deep sleep levels of adenosine triphosphate (ATP), a molecule sometimes referred to as the energy currency of life, increased in four key brain regions. Overall brain activity decreased. When researchers kept the rats awake there was no measurable energy surge.

The parts of the brain where this was observed are associated with wakefulness. One of the areas this was observed was the frontal cortex, a part of the brain associated with high-level thinking.

The authors of the study believe the flare-ups power the restorative processes only happens when during sleep. Daily waking functions may consume most of the brain’s energy, preventing restorative effects.

The Perks and Perils of Split Sleep Schedules for Shift Workers

One of the most difficult aspects of shift work is figuring out when to sleep. You may get right to sleep after work but wake up earlier than intended, alert and unable to return to sleep. It may feel fine in the afternoon, but by the time the next shift starts exhaustion sets in.

Some shift workers adapt by splitting their sleep into two shorter periods each day. It works like this: sleep 4 to 5 hours in the morning, wake up in the early afternoon, and then take a long nap 2 to 3 hours before work.

Those with split sleep schedules say it allows for more flexibility to participate in daytime and early evening activities including parenting, socializing and running errands.

A limited body of research topic suggests a split sleep schedule is no different than sleeping exclusively during the daytime. Alertness levels are about the same in both conditions. It’s up to shift workers to decide what strategy is the best fit to get the maximum amount of sleep.

A 1998 study used computer modeling to test different sleep approaches for shift workers, including split sleep schedules. Results show a long late nap may increase alertness and minimize risk of injury or mistakes when the nap is taken around 1 a.m. The unfortunate reality is most overnight shift workers don’t have that luxury.

The authors determined the next best time for a nap is leading up to the start of work. This may help but it’s likely you will find yourself struggling to stay awake for most of your shift, especially between 2 a.m. and 6 a.m.

The study included a model for sleeping exclusively during the daytime. The results were nearly identical; sleeping a full 7.5 consecutive hours in the daytime leads to the same overnight alertness levels, however reduced, as napping before work.

A NASA funded experiment by researchers at the University of Pennsylvania Medical School came up with the same conclusion. The study looked at whether astronauts and mission control personnel could perform sufficiently under nontraditional sleep schedules, including split sleep.

Researchers monitored 90 subjects in a controlled laboratory with no external time cues for 14 consecutive days. Participants were assigned to one of 18 strict sleep conditions that included a mix of split sleep schedules and full daytime sleep schedules. The control group slept at night for about eight hours. The participants were given a series of alertness tests every two hours they were awake.

There was no measurable difference between split sleep schedules and daytime sleep, as long as the total sleep length was sufficient. The authors concluded split schedules have no negative impact and may allow more lifestyle flexibility for civilian shift workers.

Both approaches have their downsides. Staying asleep through the afternoon may be a challenge, especially during the summertime. Taking a late nap may make it difficult to fall asleep after work. Insomnia is a common complaint for all types of shift workers.

There are several other things you can do to make the shift work experience more tolerable. When used properly caffeine can be a boon for shift workers. A recent study found drinking coffee at the beginning of the shift can cut down on workplace mistakes.

Bright light therapy can also help increase alertness. The Sleep Education blog recommends using a light box for 15 minute increments at your workstation during the first half of your shift. Be careful not use a light box towards the end of your shift. Exposure to bright light close to bedtime may make it difficult to sleep.

Some shift workers describe feeling a surge of energy towards the end of shifts, especially after dawn. It’s important to avoid sunlight before trying to sleep. We suggest wearing dark sunglasses on the commute home from work. Also try to make your bedroom as dark as possible, by using blackout curtains.

High temperatures and daytime noise are two other common environmental sleep disruptions for shift workers. The Sleep Education blog suggests running the air conditioning along with a loud fan or noise machine.

Slightly adjusting your sleep schedule on days off may also help your body recover from shift work related sleep deprivation.

Americans Replace Work with Sleep in Recession

Contrary to previous reports, we aren’t staying awake worrying about the recession. A new government survey shows the average American gained sleep since the housing bubble burst and unemployment rates inflated.

The Labor Department’s 2009 American Time Use Survey reports last year we spent 17 fewer minutes a day engaged in work compared to 2007. In turn, we’re sleeping an extra six minutes. Americans ages 15 and older slept an average of eight hours and 40 minutes a day.

The numbers may be discouraging on the economic front, but from a health standpoint we’re doing quite well. The AASM recommends 7 to 8 hours of sleep per night for adults.

Women seem to be getting the most rest. Survey statistics show they had eight hours and 43 minutes of sleep in 2009. Men slept for an average of eight hours and 37 minutes. We’re sleeping extra long on weekends – about 9 hours and 20 minutes a day.

Breaking down the Labor Department report further, it appears all age groups are getting more than enough sleep:

Sleep times decreased with age. This may be because adults have more responsibilities and a reduced “sleep need.” Sleep time sharply for adults ages 65 and older. This spike is contrary to research suggesting sleep disorders including insomnia are common among older adults.

Curiously, 99.8 percent of adult men reported sleeping. The other 0.2 percent is probably explained by the survey’s margin of error, which is not listed.

So what were we doing for the rest of the extra time spent not working? In typical American fashion we spent the time watching television.

Review: “Wide Awake: A Memoir of Insomnia”

In “Wide Awake: A Memoir of Insomnia” author Patricia Morrisroe provides an entertaining overview of the basics of sleep medicine and the lengths people go to find sleep.

Morrisroe has battled insomnia for most of her life. In the book she describes her frustrations of waking up most nights and never getting back to sleep, a problem that dates back to childhood.

The story is about the author as much as it is about sleep. Morrisroe’s writing style is straightforward and personal. It’s easy to identify with her as she desperately grasps for anything to help with her insomnia.

One warning to readers: “Wide Awake” does not make for good bedtime reading. The description inside the hardcover jacket advises, “Reading [“wide awake”] will promote wakefulness.” Readers with insomnia caused by bedtime anxiety should heed this warning. Reading the inner thoughts of a writer with insomnia may only perpetuate sleeplessness by suggestion.

Reading “Wide Awake” its clear Morrisroe is well-versed in the scientific background of sleep. She intelligently breaks down jargon-filled research articles found in academic journals to educate readers about various sleep disorders and treatments.

The early to middle parts of the book compellingly lay out just how ubiquitous sleep, or the lack of it, is in our technologically-driven 24-hour society. In many ways, we’re being kept from sleep; from our hospitals to the casino floors in Las Vegas bleary-eyed workers try to survive day-by-day.

The narrative takes some distracting detours in its later acts. It seems the whole purpose of Morrisroe’s adventure in arctic Sweden is to show readers “look at this exotic place where I couldn’t sleep.” The segment about the new-age dream retreat and costume ball seemed similarly off-track.

Morrisroe gives a somewhat controversial account of her experiences with sleep clinicians. Most disappointingly, she did not adhere to Cognitive Behavioral Therapy, the AASM recommended treatment for primary insomnia. Based on her accounts, her therapist wasn’t the right fit. She describes an almost adversarial relationship filled with friction. In this case it’s best to switch therapists and find a mental health professional with a more compatible disposition.

Ending Spoiler Alert: Contrary to the books description, Morrisroe never finds the answer to her insomnia, but she does come close. Meditation techniques seem to temporarily work by reducing her sleep anxiety. But it’s an environmental factor that ultimately keeps her up at night. The book closes with her sitting on her porch at 4 a.m. staring at the full moon, unable to sleep but relaxed from meditation.

Energy Pods let Google Employees Snooze in Style

Here’s one big reason why Google is consistently near the top of every annual “Best Companies to Work For” list. Among the many well-documented perks of working for Google is the leeway to step away from the desk and take a nap. Google stands out from the other companies with nap rooms by offering a stylistically futuristic sleep pod right out of the show Caprica.

That oversized salon hair dryer you see above is a state-of-the-art Energy Pod made by Metronaps. The reclining bed underneath the big white visor looks a lot like a dental chair.

Features include a built-in music player that produces soothing sounds and an alarm that wakes users up with a gentle combination of lights and vibration.

The Metronaps Energy Pod retails for around $8,000 - no small price, but still less expensive than ludicrously priced European luxury beds.

Google’s solution to workplace fatigue appears to be a preferable alternative to lunchtime car naps or sneaky catnaps in the bathroom stalls. It’s good to see the world’s most influential tech firm notice the building scientific evidence of the performance benefits of napping. Now if only more companies would adopt this practice maybe we’ll all stop looking down on workplace naps... I’m looking at you Ken Griffey Jr.