Category Archives: Sleep

Press-release just in – Deep Sleep: Researchers Discovery How To Simulate Slow Wave Activity:

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During slow wave activity, which occupies about 80 percent of sleeping hours, waves of electrical activity wash across the brain, roughly once a second, 1,000 times a night. In a new paper being published in the scientific journal PNAS, Tononi and colleagues, including Marcello Massimini, also of the UW-Madison School of Medicine and Public Health, described the use of transcranial magnetic stimulation (TMS) to initiate slow waves in sleeping volunteers. The researchers recorded brain electrical activity with an electroencephalograph (EEG).
A TMS instrument sends a harmless magnetic signal through the scalp and skull and into the brain, where it activates electrical impulses. In response to each burst of magnetism, the subjects’ brains immediately produced slow waves typical of deep sleep, Tononi says. “With a single pulse, we were able to induce a wave that looks identical to the waves the brain makes normally during sleep.”
The researchers have learned to locate the TMS device above a specific part of the brain, where it causes slow waves that travel throughout the brain. “We don’t know why, but this is a very good place to evoke big waves that clearly travel through every part of the brain,” Tononi says.
Scientists’ interest in slow waves stems from a growing appreciation of their role in sleep, Tononi says. “We have reasons to think the slow waves are not just something that happens, but that they may be important” in sleep’s restorative powers. For example, a sleep-deprived person has larger and more numerous slow waves once asleep. And as sleep proceeds, Tononi adds, the slow waves weaken, which may signal that the need for sleep is partially satisfied.
Creating slow waves on demand could someday lead to treatments for insomnia, where slow waves may be reduced. Theoretically, it could also lead to a magnetically stimulated “power nap,” which might confer the benefit of eight hours sleep in just a few hours.
Before that happens, however, Tononi must go further and prove that artificial slow waves have restorative benefits to the brain. Such an experiment would ask whether sleep with TMS leads to greater brain restoration than an equal amount of sleep without TMS.
Although an electronic power-napper sounds like a product whose time has come, Tononi is chasing a larger quarry: learning why sleep is necessary in the first place. If all animals sleep, he says, it must play a critical role in survival, but that role remains elusive.
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Once the paper shows up on the PNAS site, I’ll see if there is more I need to add to this story.

Good. Everyone expected it, but it is nice to have it tested and confirmed. Makes life easier and research cheaper.
Measuring Movement To Assess And Manage Sleep Disorders:

Actigraphy, the use of a portable device that records movement over extended periods of time, and has been used extensively in the study of sleep and circadian rhythms, provides an acceptably accurate estimate of sleep patterns in normal, healthy adult populations and in-patients suspected of certain sleep disorders, according to practice parameters published in the April 1st issue of the journal SLEEP.

This means that patients can go about their normal lives instead of checking into a sleep lab. They just need to wear the “watch” at all times and bring/send in the data on a regular basis.

Sandra has a post about an interesting case of a person who commited a crime (and was acquitted) while sleepwalking. The term “sleep disorder” was used as a defence.
But, is it a disorder at all? It naturally occurs in a proportion of human population. It is called a disorder because it does not happen to everyone and it can be dangerous for the sleepwalker or the people around him/her. Nobody is really trying to treat it, except for making sure that habitual sleepwalkers have a safe environment in which to walk at night (multiple complicated locks on the doors, etc).
Yes, you are completely unconscious, you cannot plan what to do once you are asleep and walking, you have no awareness of what you are doing while you are sleepwalking, and you have no recollection of what you did once you wake up. This would make acquittal a correct decision, without any need to invoke a ‘disorder’.
Yet, a person who would commit crime when awake will commit one when sleepwalking, and person who would never do so while awake is unlikely to get started while asleep.
Michael Rack does not have much on the topic on his blog, and neither does Michael Breus, but there is more here.
This is also similar to the case of sexsomnia.
So, what do you think? Is this a good alibi? If you did something bad while unconscious, would you want to be acquitted?

This is interesting:
Study: Sleep linked to brain cell creation:

The Proceedings of the National Academy of Science research on rats found that the hippocampus portion of the brain was directly affected by a lack of sleep for a long period, the BBC reported.
By depriving rats of sleep for 72 hours, the researchers found that those animals consequently had increased amounts of the stress hormone corticosterone, and produced significantly fewer new brain cells in the hippocampus.
When the rats’ sleep patterns were returned to normal a week later, their levels of nerve-cell production remained hindered for two weeks.
The lack of production appeared to prompt the brain to increase its efforts to maintain an appropriate balance.
British sleep expert Dr. Neil Stanley called the finding “interesting,” but said more study on sleep depravation might be useful.
“It would be interesting to see if partial sleep deprivation — getting a little bit less sleep every night than you need — had the same effect,” he told the BBC.

But does that have anything to do with memory?

Jonah has a good rundown on a new paper on the neuroscience.

Memory Improves After Sleep Apnea Therapy:

Patients with obstructive sleep apnea (OSA) may improve their memory by using continuous positive airway pressure (CPAP). A new study published in the December issue of CHEST, the peer-reviewed journal of the American College of Chest Physicians (ACCP), shows that the majority of patients with OSA, who were memory-impaired prior to treatment, demonstrated normal memory performance after 3 months of optimal CPAP use. The study also showed that memory improvement varied based on CPAP adherence. Patients who used CPAP for at least 6 hours a night were nearly eight times as likely to demonstrate normal memory abilities compared with patients who used CPAP for 2 or fewer hours a night.

Sleep apnea is a condition in which airways close and induce a temporary brief awakening. Patients are, thus, unable to go through normal cycles of sleep phases, resulting in, effectively, sleep deprivation. This study is a nice additional evidence for the importance of sleep in learning and memory.

Recovering alcoholics with poor sleep perceptions will likely relapse:

“The usual perception of alcohol’s effects on sleep in nonalcoholics is that it helps sleep,” explained Deirdre A. Conroy, the corresponding author who conducted the research while a postdoctoral fellow at the University of Michigan. “In truth, alcohol may help people fall asleep but it usually leads to poor quality sleep in the second half of the night and overall less deep sleep. As people drink more regularly across nights to fall asleep, they become tolerant to the sedating effects of alcohol and subsequently use more alcohol each night to help fall asleep. This escalation in drinking can lead to alcoholism.”

Sleep: it’s required:

“….short sleep can hasten the arrival of the inevitable long sleep”

Occasionally, an article on sleep in the newspapers is actually good. Like this one.

You can see some highlights here.

The latest issue of Archives of Internal Medicine is devoted to sleep. The articles are freely available. Here is the press release:
Incorporate Sleep Evaluation Into Routine Medical Care, Expert Says

Sleep is an integral part of health, and assessment of sleep habits should be a standard part of medical care, according to an editorial in the September 18 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. The issue is devoted to studies of sleep and health.
“The theme that emerges throughout this issue is that sleep serves as an indicator of health and quality of life and therefore is highly and directly relevant to the practice of medicine,” write guest editor Phyllis C. Zee, M.D., Ph.D., and Fred W. Turek, Ph.D., of Northwestern University Feinberg School of Medicine, Chicago.
“Indeed, numerous studies have recently shown that sleep disorders are often comorbid with a broad range of medical and psychiatric conditions and also have a negative impact on health, mood and quality of life,” they continue. “Increasing evidence also points to a bidirectional relationship between sleep and health; that is, sleep disturbances contribute to the development of or increase the severity of various medical and psychiatric disorders, and these same disorders result in poor sleep quality.”
Research results published in this issue of Archives of Internal Medicine “further our understanding of the relationship of sleep and health,” Drs. Zee and Turek write. Studies appearing in this issue find that:
* Fewer hours of sleep may contribute to poor health in young adults, according to an international survey of more than 17,000 university students
* Those in rural areas who sleep fewer hours appear to have a higher average body mass index
* The immune system may play a role in narcolepsy, a disorder marked by a sudden and uncontrollable urge to sleep
* Children with chronic illnesses, especially those on ventilators, tend to have parents with disrupted sleep
* The immune system may be affected by a lack of sleep, altering blood chemistry in a way that potentially contributes to inflammation and a variety of diseases
Over the past decade, it has become apparent that voluntarily limited sleep, as well as sleep disorders such as insomnia and restless legs syndrome, can negatively affect overall health–a connection emphasized by the increasing legitimacy of sleep medicine as a specialty. In addition, medications used to treat a number of physical and psychiatric disorders can affect sleep, making evaluation for sleep problems essential for those following such regimens. “At the very least, assessment of sleep quantity and quality should be integrated into the routine review of systems,” Drs. Zee and Turek conclude. “Sleep is an indicator of health, and sufficient sleep quantity and good quality should be considered as an essential component of a healthy lifestyle, as much as exercise and nutrition.”

I’ve heard of this before, but now I see an actual study has been published:

There’s more to a good night’s rest than going to bed early. Sleeping comes easiest and lasts longest for the wealthy, white, and female. Reporting her findings in the June 1 American Journal of Epidemiology, health-studies associate professor Diane Lauderdale, AM’78, AM’81, followed the sleep habits of 669 Americans aged 35 to 50 and found that those with a yearly income of less than $16,000 spend longer in bed than those making $100,000 or more, but they sleep less because their “sleep latency,” the amount of time spent lying in bed awake, stretches to nearly an hour.

Using both self-kept sleep logs and wrist-activity monitors, Lauderdale also discovered that people sleep less than they realize: although participants reported averaging nearly seven hours per night, measured sleep was only about six.

So, do rich people worry less? Are they more exhausted by the end of the day? Do they have more comfortable beds? Or do they have better sleeping conditions in their bedrooms, e.g., darkness and silence, with no TV or other people talking?
(Hat-tip: Jonah)

Sawing The ZZZZZs: Getting Old Needn’t Keep You Awake, Geriatricians Say:

“Patients must be educated on normal sleep-related changes but also made aware that sleep problems are not a part of normal aging.”

Again we have the problem with the use of the word “normal”! Fragmentation of sleep in old age is “normal” in a sense that it happens to most people and most other mammals. Just because it is unpleasant and potentially bad for one’s health does not make it not normal. Yet, just like we treat bad eyeseight with glasses, we can alleviate sleep problems in the elderly with a variety of strategies outlined in this article. Doing something “artifical” about something that is “normal” can make the quality of life be more “normal”.

Found on the Talk About Sleep forums:

We here at Talk About Sleep have recently learned of a very interesting study of sleep and sleep disorders being conducted by a Ph.D. student at the University of Minnesota. Matthew Wolf-Meyer is a medical anthropologist and is interested in hearing about your personal experiences as a sleep disorder sufferer, as well as the experiences of your family members.
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From what we understand, this is the first social study of sleep disorders and their impacts on the lives of patients and their families. This study could have positive consequences for school and work, so participating could be very important in helping change the social ramifications of sleep disorders.

You can read more about the project here and volunteer to participate here:

The purpose of this study is to examine the ways in which ideas about everyday life in American society are shaped by and shape ideas about sleep. In other words, how do dominant ideas about proper times of sleep shape ideas about proper times for school, work, and family life? How do these ideas impact people with sleep disorders and their friends and loved ones? Are there better ways to organize work, school, and family life so as to minimize interference with the need for sleep?

(Hat-tip: NBM – the Night Owl)