Rhythmic Human:
Carl Zimmer: How Your Brain Can Control Time: For 40 years, psychologists thought that humans and animals kept time with a biological version of a stopwatch. Somewhere in the brain, a regular series of pulses was being generated. When...
Posted on July 19, 2008 1:06 PM • 0 Comments •
Today in PLoS Genetics: a nice review of some interest to my readers: When Clocks Go Bad: Neurobehavioural Consequences of Disrupted Circadian Timing by Alun R. Barnard and Patrick M. Nolan: Progress in unravelling the cellular and molecular basis of...
Posted on May 30, 2008 11:21 AM • 3 Comments •
In the Journal of Circadian Rhythms: A new approach to understanding the impact of circadian disruption on human health (pdf): Background Light and dark patterns are the major synchronizer of circadian rhythms to the 24-hour solar day. Disruption of circadian...
Posted on May 30, 2008 8:36 AM • 0 Comments •
No matter how cutesy the acronim SAD is. Joseph reports on a study that links SAD to serotonin. But serotonin itself may not be necessary to understand how SAD works, though an intimate link between serotonin and melatonin (the former...
Posted on May 23, 2008 8:34 AM • 1 Comments •
If you are one of the few of my readers who actually slogged through my Clock Tutorials, especially the difficult series on Entrainment and Phase Response Curves, you got to appreciate the usefulness of the oscillator theory from physics in...
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Posted on May 22, 2008 4:58 PM • 1 Comments •
What it really means when we are talking about babies "sleeping through the night"
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Posted on May 20, 2008 4:58 PM • 5 Comments •
The fourth part of a four-part series on the topic, this one from April 02, 2006.......
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Posted on May 19, 2008 4:59 PM • 1 Comments •
This is the third part of the series on the topic, from April 01, 2006......
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Posted on May 18, 2008 4:57 PM • 2 Comments •
Earlier this year, during the National Sleep Awareness Week, I wrote a series of posts about the changes in sleep schedules in adolescents. Over the next 3-4 hours, I will repost them all, starting with this one from March 26,...
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Posted on May 17, 2008 4:53 PM • 1 Comments •
This kind of ignorant bleating makes me froth at the mouth every time - I guess it is because this is my own blogging "turf". One of the recurring themes of my blog is the disdain I have for people...
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Posted on May 16, 2008 4:59 PM • 4 Comments •
My regular readers are probably aware that the topic of adolescent sleep and the issue of starting times of schools are some of my favourite subjects for a variety of reasons: I am a chronobiologist, I am an extreme "owl"...
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Posted on May 15, 2008 7:53 PM • 23 Comments •
Book excerpt in today's Wall Street Journal: Chapter 6: Wired: It is likely that insomnia will increase with the expansion of the 24-hour economy into more and more lives, and more of each life, because wakefulness and the wired world...
Posted on February 29, 2008 7:02 AM • 0 Comments •
Shift Work May Be Cancer Risk: In an announcement to be published Saturday in the journal Lancet Oncology, the International Agency for Research on Cancer, part of the World Health Organization, will label shift work as a "probable cause" of...
Posted on November 30, 2007 9:18 AM • 2 Comments •
I am sure I have ranted about the negative effects of DST here and back on Circadiana, but the latest study - The Human Circadian Clock's Seasonal Adjustment Is Disrupted by Daylight Saving Time (pdf) (press releases: ScienceDaily, EurekAlert) by...
Posted on October 24, 2007 9:45 PM • 31 Comments •
Symposium Light, Performance and Quality of Life is on Thursday, 8 November 2007 in Eindhoven, the Netherlands: Introduction The ancient Greek already referred to the wholesome effects of the (sun)light on mankind. Ever since the industrialization, more and more people...
Posted on September 20, 2007 3:38 PM • 1 Comments •
From the Independent: The head has identified research which says that teenagers would be more likely to take in what they are learning if they started school two hours later. He is considering changing the school timetable for sixth-formers as...
Posted on September 18, 2007 12:09 PM • 4 Comments •
NBM found an excellent online article (which I have seen before but I forgot) depicting Phase-Response Curves (PRC) to injections of melatonin in humans, rodents and lizards. Note how the shape is roughly opposite to that of a PRC to...
Posted on August 12, 2007 10:34 PM • 1 Comments •
Why are Orli and Joseph thinking about this in the middle of the summer? I am happy (and South enough). I am wondering if people with SAD living in the high latitudes either moved South or, being all gloomy, had...
Posted on August 10, 2007 2:39 PM • 12 Comments •
If you are one of the few of my readers who actually slogged through my Clock Tutorials, especially the difficult series on Entrainment and Phase Response Curves, you got to appreciate the usefulness of the oscillator theory from physics in...
Posted on July 31, 2007 1:57 PM • 1 Comments •
More stuff from SLEEP 2007, the 21st Annual Meeting of the Associated Professional Sleep Societies: Sleep Deprivation Affects Eye-steering Coordination When Driving: Driving a vehicle requires coordination of horizontal eye movements and steering. Recent research finds that even a single...
Posted on June 14, 2007 2:26 AM • 1 Comments •
This is the first study I know that directly tested this - the effects of rotating shifts on longevity - in humans, though some studies of night-shift nurses have shown large increases in breast cancers, stomach ulcers and heart diseases,...
Posted on April 22, 2007 1:06 PM • 7 Comments •
Apparently, in Denmark, the 'larks' (early-risers) are called 'A-people' while 'owls' (late-risers) are 'B-people'. We all know how important language is for eliciting frames, so it must feel doubly insulting for the Danish night owls. Today, in the age of...
Posted on March 23, 2007 2:21 PM • 4 Comments •
It has been known for quite a while now that bipolar disorder is essentially a circadian clock disorder. However, there was a problem in that there was no known animal model for the bipolar disorder. Apparently that has changed, if...
Posted on March 20, 2007 2:29 AM • 0 Comments •
This is the time when everyone is talking about the Daylight Saving Time and I always feel pressure to blog about it from a chronobiological perspective. And I always resist. As I will this year. So, here are a couple...
Posted on March 12, 2007 1:03 PM • 3 Comments •
The 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,...
Posted on March 12, 2007 12:46 AM • 1 Comments •
This is a story about two mindsets - one scientific, one not - both concerned with the same idea but doing something very different with it. Interestingly, both arrived in my e-mail inbox on the same day, but this post...
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Posted on February 28, 2007 9:50 AM • 4 Comments •
Matt found a conference paper that shows that the risk of pre-term birth is the lowest in spring, rising through summer and fall and the greatest in winter. The paper, IMHO erroneously, focuses on the time of conception (because it...
Posted on February 6, 2007 4:35 PM • 2 Comments •
In light of my post earlier today about the discrepanices between 'real time' and 'clock time' (or 'social time'), it is heartening that the Parliament in the U.K. wisely decided not to switch their clocks to the time the rest...
Posted on January 31, 2007 4:58 PM • 4 Comments •
While study of Time-Perception is, according to many, a sub-discipline of chronobiology, I personally know very little about it. Time perception is defined as interval timing, i.e., measuring duration of events (as opposed to counting, figuring which one of the...
Posted on January 31, 2007 3:59 PM • 1 Comments •
Time Zones as experimental tools - if you live in a Big City you are just like one of my experimental subjects!
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Posted on January 31, 2007 11:54 AM • 8 Comments •
If 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...
Posted on January 29, 2007 12:28 PM • 4 Comments •
Nicole 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...
Posted on January 27, 2007 10:49 PM • 0 Comments •
I 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...
Posted on January 26, 2007 11:37 PM • 0 Comments •
Adjust your sleep number for the best performance! Or, what does your sleep number say about your performance?...
Posted on January 22, 2007 9:53 AM • 1 Comments •
For science bloggers, a study older than a week is often too old to blog about. For scientists, last five years of literature are the most relevant (and many grad students, unfortunately, never read the older stuff). I thought that...
Posted on December 20, 2006 5:25 PM • 0 Comments •
Here is the second guest-post by Heinrich (from March 20, 2005):...
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Posted on December 20, 2006 11:02 AM • 0 Comments •
Well, not me, but people who know what I know. Heinrich aka Sir Oolius explains how the US military uses the knowledge of circadian rhythms and sleep in applications to torture. Just place the prisoners in a state of perpetual...
Posted on December 18, 2006 5:48 PM • 3 Comments •
Now behind the Wall, but plenty of excerpts available in this March 26, 2005 post......
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Posted on December 13, 2006 10:53 AM • 1 Comments •
How does that work? (April 03, 2005)...
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Posted on December 11, 2006 11:00 AM • 0 Comments •
This is an appropriate time of year for this post (February 05, 2006)......
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Posted on December 6, 2006 10:49 AM • 8 Comments •
The original title of this post - "Diurnal rhythm of alcohol metabolism" - was more correct, but less catchy (from February 21, 2006)....
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Posted on November 29, 2006 10:51 AM • 0 Comments •
A short-but-sweet study (March 18, 2006):...
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Posted on November 27, 2006 10:59 AM • 5 Comments •
Does eating turkey meat make you sleepy? Some people say Yes, some people say No, and the debate can escalate into a big fight.
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Posted on November 22, 2006 10:53 AM • 6 Comments •
Apparently, the timing of sporting events in Beijing, probably driven by needs of American TV audiences, did not take into consideration the best time of day for athletic performance. But who cares about athletes, or even about breaking Olympic and...
Posted on October 31, 2006 8:57 AM • 0 Comments •
This week's Ask a ScienceBlogger question is: A reader asks: Is severely regulating your diet for a month each year, as Muslims do during Ramadan, good for you? There is no way I can get out of this one! As...
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Posted on October 18, 2006 2:15 PM • 0 Comments •
I tend to rant about sleep in adolescents for various reasons, but other people focus on other age groups. Infants are one such group, interesting because it takes a while for their circadian rhythms to consolidate resulting in "sleeping through...
Posted on October 18, 2006 10:00 AM • 4 Comments •
Nothing too complicated today, but something you should all know.
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Posted on October 16, 2006 10:00 AM • 0 Comments •
Bill Bailey reports that an organization called 'Screening for Mental Health' offers free screenings for Seasonal Affective Disorder (SAD). But then, they push drugs on people they "diagnose". The only problem - SAD is not treated with drugs!!! It is...
Posted on October 5, 2006 4:09 PM • 6 Comments •
Study says no video games on school nights: According to Dr. Iman Sharif, the results were clear-cut. "On weekdays, the more they watched, the worse they did," said Dr. Sharif. Weekends were another matter, with gaming and TV watching habits...
Posted on October 5, 2006 11:59 AM • 2 Comments •
Since every chemical induces a different response in the body dependent on the time of day when it is administered, I am not surprised that this also applies to caffeine: A new study at the Université de Montréal has concluded...
Posted on October 4, 2006 10:57 AM • 1 Comments •
Over 1.6 Million Americans Use Alternative Medicine For Insomnia Or Trouble Sleeping: A recent analysis of national survey data reveals that over 1.6 million American adults use some form of complementary and alternative medicine (CAM) to treat insomnia or trouble...
Posted on September 20, 2006 3:42 PM • 5 Comments •
So, is extreme "larkiness" due to overphosphorilation or underphosphorilation of PERIOD2? Hypotheses get tested, studies conflict with each other and, in the end, there is a resolution. In this case, we are still waiting for resolution. Science marches on....
Posted on September 19, 2006 10:15 PM • 0 Comments •
Indian Creek dedicates new Upper School: Mrs. Mattingly highlighted the major components of the college preparatory curriculum that fills the school day beginning at 8:50 a.m. and continues until 5 p.m. The hours are designed to accommodate teens' circadian rhythms....
Posted on September 15, 2006 9:27 PM • 0 Comments •
Students not getting enough sleep: College students may believe they are being more productive when they sleep less, but in reality it is causing harm to their bodies. The National Sleep Foundation points out that receiving less than six hours...
Posted on September 15, 2006 8:57 AM • 1 Comments •
The fourth part of a four-part series on the topic.
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Posted on September 11, 2006 11:52 AM • 0 Comments •
This is the third part of the series on the topic.
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Posted on September 11, 2006 10:52 AM • 0 Comments •
The second post on the topic. A couple of links are broken due to medieval understanding of permalinks by newspapers, but you will not miss too much, I hope....
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Posted on September 11, 2006 9:58 AM • 0 Comments •
The first in a series of posts about the changes in sleep schedules in adolescents.
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Posted on September 11, 2006 8:54 AM • 3 Comments •
This kind of ignorant bleating makes me froth at the mouth every time - I guess it is because this is my own blogging "turf". One of the recurring themes of my blog is the disdain I have for people...
Posted on September 10, 2006 5:42 PM • 9 Comments •
Do pilots get enough rest?: -------------------------snip--------------------- The federal rules on pilot duty hours and rest periods aren't the most comprehensible of reads. One rule allows airlines to schedule pilots to fly for eight hours or less during a 24-hour period...
Posted on September 10, 2006 4:24 PM • 0 Comments •
The Center for Health Design Research has issued its Report on The Impact of Light on Outcomes in Healthcare Settings. You can download the entire report as PDF: Light impacts human health and performance by enabling performance of visual tasks,...
Posted on September 8, 2006 7:59 AM • 2 Comments •
This is a good article about changes in sleep patterns that occur with old age....
Posted on September 7, 2006 7:20 AM • 1 Comments •
Hypotheses leading to more hypotheses.
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Posted on September 5, 2006 10:59 AM • 0 Comments •
Melatonin improves mood in winter depression: Alfred Lewy and his colleagues in the OHSU Sleep and Mood Disorders Lab set out to test the hypothesis that circadian physiological rhythms become misaligned with the sleep/wake cycle during the short days of...
Posted on August 31, 2006 7:53 AM • 0 Comments •
Three old posts about the connection between circadian clocks and the bipolar disorder.
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Posted on August 28, 2006 10:54 AM • 15 Comments •
Just a few recommendations, if you are interested in these topics.
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Posted on August 21, 2006 10:58 AM • 0 Comments •
Many Commercial Drivers Have Impaired Performance Due To Lack Of Sleep Truck drivers who routinely get too little sleep or suffer from sleep apnea show signs of fatigue and impaired performance that can make them a hazard on the road,...
Posted on August 17, 2006 2:59 PM • 1 Comments •
Different strokes occur at different times Different types of strokes occur most often at different times of day say scientists at Iwate Medical University in Iwate, Japan. The team based their findings on data from 12,957 cases of first-ever stroke...
Posted on August 17, 2006 2:38 AM • 0 Comments •
This is an interesting idea: A novel way to advance the circadian cycle has been proposed as a way to solve the problem associated with the early starting times of middle and high schools. It has been recognized for some...
Posted on August 10, 2006 1:59 PM • 12 Comments •
Today's New York Times has a good article about jet-lag: The Science of Zzzzz's. I am glad to hear that JetBlue is using scientific advice in helping their pilots be fresh and alert, especially now that JetBlue has started flying...
Posted on August 8, 2006 1:31 PM • 0 Comments •
Oversimplified, but much believed idea: Many cancer drugs target cells during cell division. Healthy cells divide at a particular time of day (exact timing may differ between cell types). Cancer cells are not under the control of the circadian clock...
Posted on August 4, 2006 12:31 PM • 2 Comments •
A number of media outlets are reporting on the new Duke University study on the effects of time-of-day on the outcome of surgery: Patients who undergo surgery late in the afternoon are more likely to experience unexpected adverse events related...
Posted on August 3, 2006 1:38 PM • 1 Comments •
