sleep
clock | April 8, 2007Good. 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…
clock | March 14, 2007Sandra 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…
clock | March 11, 2007The most exciting thing about this study is that this is, as far as I am aware, the first instance in which it was shown that a circadian clock gene has any effect on sleep apart from timing of it, i.e., on some other quality or quantity of sleep (not just when to fall asleep and wake up, but also the depth of sleep and the amount of sleep need):
Performing Under Sleep Deprivation: Its In Your Genes:
People are known to differ markedly in their response to sleep deprivation, but the biological underpinnings of these differences have remained difficult to identify.
Researchers have now found…
clock | February 10, 2007This 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…
clock | February 6, 2007Slow-wave Activity During Sleep Affected By Quality, Intensity Of Wakefulness:
A study published in the February 1st issue of the journal SLEEP provides a first direct demonstration that the "quality" and "intensity" of wakefulness can affect slow-wave activity (SWA) during subsequent sleep.
According to Chiara Cirelli, MD, PhD, of the University of Wisconsin-Madison, one of the authors of the study, the importance and novelty of the paper lies in the demonstration that the crucial factor linking physiological waking activity to sleep SWA is synaptic plasticity, notably synaptic potentiation…
clock | January 29, 2007If you discover a brain chemical which, when missing or malfunctioning (due to a mutation in its receptor) abruptly puts people and animals to sleep when they don't want to - a condition called narcolepsy - then you can work on creating a drug that acts in the opposite way and induces sleep when you want to.
Apparently, that is what a Swiss team just did (Nature news report here and Nature blog commentary here). The drug, still without a sexy name, is known by its "code-name" ACT-078573.
The target of the drug is the orexin system. Orexins (also known as hypocretins - the discovery was…
clock | January 27, 2007Nicole Eugene recently defended her Masters Thesis called Potent Sleep: The Cultural Politics of Sleep (PDF) on a topic that I find fascinating:
Why is sleep, a moment that is physiologically full and mentally boundless, thought to be a moment of absence and powerlessness? Where did this devalued notion of sleep come from and how can we situate sleep studies within a continuation of a historical processes and economic infuences? In other words, how does sleep effect and exist within systems of power? To answer these questions I turn to a range of scholarship and theoretical studies to examine…
clock | January 26, 2007I was too busy with the conference so I missed the NPR Morning Edition story on one of my favourite subjects: Adolescent Sleep, which was followed by two more stories on the same subject! I am glad to see this topic becoming this prominent.
Hat-tip: Mind Hacks
clock | December 20, 2006Here is the second guest-post by Heinrich (from March 20, 2005):
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Here is the #2 guest contribution by Heinrich (not Heindrocket) of She Flies With Her Own Wings (http://coeruleus.blogspot.com/):
Most of this post was inspired by a grand rounds / journal club given by David Dinges about two weeks ago based on years of his own research and large surveys. One line of argument in the presentation that I thought was particularly interesting - one that we as sleep researchers might want to remember when we write grants and perform our…
clock | December 18, 2006Back in March 2005, I asked Heinrich of the She Flies With Her Own Wings blog to guest-post on Circadiana. He wrote two nice posts and this is the first of them (March 18, 2005). Perhaps I can get him to do some more...
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I am really excited to introduce to you my first guest blogger here on Circadiana, Heinrich, not Hindrocket whose blog, She Flies With Her Own Wings (http://coeruleus.blogspot.com/) is a worthy daily read. Heinrich does research on mammalian clocks and sleep, and his first contribution is this post…
clock | December 17, 2006Fluid Displacement From Legs To Neck Can Lead To Obstructive Sleep Apnea:
When a person lies down, a small amount of fluid displaced from the legs to the base of the neck can narrow soft tissue around the throat and increase airflow resistance in the pharynx by more than 100 percent, predisposing the person to obstructive sleep apnea.
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In obstructive sleep apnea, a blockage in the throat or upper airway causes victims to repeatedly stop breathing long enough to decrease the amount of oxygen in the blood and increase the carbon dioxide.
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"Our…
clock | December 13, 2006Memory 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…
clock | December 13, 2006Now behind the Wall, but plenty of excerpts available in this March 26, 2005 post...
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Ha! The New York Times has this neat article, that is almost half as good as my early (and so far most frequently linked) post "Everything You Always Wanted To Know About Sleep". Here are some excerpts, go read the rest:
The Crow of the Early Bird
THERE was a time when to project an image of industriousness and responsibility, all a person had to do was wake at the crack of dawn. But in a culture obsessed with status--in which every…
clock | November 26, 2006Recovering 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…
clock | October 26, 2006
There is nothing easier than taking a bad paper - or a worse press release - and fisking it with gusto on a blog. If you happen also to know the author and keep him in contempt, the pleasure of destroying the article is even greater.
It is much, much harder to write (and to excite readers with) a blog post about an excellent paper published by your dear friends. But I'll try to do this now anyway (after the cut).
Paul Shaw is a friend, and Indrani Ganguli is a good, good, good friend. Faculty and graduate students in biology are usually a pretty smart lot. A subset of those, as self-…
clock | October 24, 2006Sleep: it's required:
"....short sleep can hasten the arrival of the inevitable long sleep"
clock | October 20, 2006Occasionally, an article on sleep in the newspapers is actually good. Like this one.
clock | October 20, 2006Shelley went to the Society for Neuroscience meeting and saw a talk on sleep deprivation, memory and hippocampus.
clock | October 19, 2006Shorter Nightly Sleep In Childhood May Help Explain Obesity Epidemic:
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This research shows that shorter sleep duration disturbs normal metabolism, which may contribute to obesity, insulin resistance, diabetes, and cardiovascular disease. Even two to three nights of shortened sleep can have profound effects, the laboratory data suggest.
One study indicated that insufficient sleep at the age of 30 months was associated with obesity at the age of 7, suggesting that this could programme the part of the brain regulating appetite and energy expenditure,…