The aim of this study was to compare the quantity/quality of sleep obtained by people living on split and consolidated sleep-wake schedules. The study had a between-groups design, with 13 participants in a consolidated condition (all males, mean age of 22.5yr) and 16 participants in a split condition (all males, mean age of 22.6yr). Both conditions employed forced desynchrony protocols with the activity:rest ratio set at 2:1, but the consolidated condition had one sleep-wake cycle every 28h (9.33+18.67), while the split condition had one sleep-wake cycle every 14h (4.67+9.33). Sleep was assessed using polysomnography. Participants in the split and consolidated conditions obtained 4.0h of sleep per 14h and 7.6h of sleep per 28h, respectively. Some differences between the groups indicated that sleep quality was lower in the split condition than the consolidated condition: the split sleeps had longer sleep onset latency (9.7 vs. 4.3min), more arousals (7.4 vs. 5.7 per hour in bed), and a greater percentage of stage 1 sleep (4.1% vs. 3.1%), than the consolidated sleeps. Other differences between the groups indicated that sleep quality was higher in the split condition than the consolidated condition: the split sleeps had a lower percentage of wake after sleep onset sleep (11.7% vs. 17.6%), and a greater percentage of slow wave sleep (30.2% vs. 23.8%), than the consolidated sleeps. These results indicate that the split schedule was not particularly harmful, and may have actually been beneficial, to sleep. Split work-rest schedules can be socially disruptive, but their use may be warranted in work settings where shiftworkers are separated from their normal family/social lives (e.g., fly-in fly-out mining) or where the need for family/social time is secondary to the task (e.g., emergency response to natural disasters).
Sleep as a Competitive Advantage
Too many of us live by the myth that one less hour of sleep gives us one more hour of productivity, Tony Schwartz writes in the Life@Work column. In reality, lost sleep not only leaves us more fatigued, but also takes a toll on our cognitive capacity.
Sleep as a Competitive Advantage
Too many of us live by the myth that one less hour of sleep gives us one more hour of productivity, Tony Schwartz writes in the Life@Work column. In reality, lost sleep not only leaves us more fatigued, but also takes a toll on our cognitive capacity.
Why Seven Hours of Sleep Might Be Better Than Eight
Several studies have found that seven hours a night is the best amount of sleep in order to function the next day—not eight, as was long believed.
Sleep: Educational Impact and Habit Formation
In a field experiment among US university students, incentives for sleep increase both sleep and academic performance. Our primary intervention pairs bedtime reminders with morning feedback and immediate rewards for sleeping at least 7 hours on weeknights. The intervention raises the share of weeknights with 7+ hours of sleep by 26% and average sleep by 19 minutes during a 4-week treatment period, with posttreatment effects of 8 minutes. Immediate incentives outperform both delayed incentives and reminders/feedback alone during treatment but have no distinguishable impacts posttreatment. The primary intervention improves average semester course performance by 0.075–0.089 grade points, a 0.10–0.11 standard deviation increase. Our results demonstrate that incentives targeting sleep can be a cost-effective approach to improve educational outcomes.
Sleep Deficit: The Performance Killer
Reprint: R0610B Companies today glorify the executive who logs 100-hour workweeks, the road warrior who lives out of a suitcase in multiple time zones, and the negotiator who takes a red-eye to make an 8 AM meeting. But to Dr. Charles A. Czeisler, the Baldino Professor of Sleep Medicine at Harvard Medical School, this kind of corporate behavior is the antithesis of high performance. In fact, he says, it endangers employees and puts their companies at risk. In this interview, Czeisler describes four neurobiological functions that affect sleep duration and quality as well as individual performance. When these functions fall out of alignment because of sleep deprivation, people operate at a far lower level of performance than they would if they were well rested. Czeisler goes on to observe that corporations have all kinds of policies designed to protect employees—rules against smoking, sexual harassment, and so on—but they push people to the brink of self-destruction by expecting them to work too hard, too long, and with too little sleep. The negative effects on cognitive performance, Czeisler says, can be similar to those that occur after drinking too much alcohol: “We now know that 24 hours without sleep or a week of sleeping four or five hours a night induces an impairment equivalent to a blood alcohol level of .1%. We would never say, ‘This person is a great worker! He’s drunk all the time!’ yet we continue to celebrate people who sacrifice sleep for work.” Czeisler recommends that companies institute corporate sleep policies that discourage scheduled work beyond 16 consecutive hours as well as working or driving immediately after late-night or overnight flights. A sidebar to this article summarizes the latest developments in sleep research.
The brain functional connectome is robustly altered by lack of sleep
Sleep is a universal phenomenon necessary for maintaining homeostasis and function across a range of organs. Lack of sleep has severe health-related consequences affecting whole-body functioning, yet no other organ is as severely affected as the brain. The neurophysiological mechanisms underlying these deficits are poorly understood. Here, we characterize the dynamic changes in brain connectivity profiles inflicted by sleep deprivation and how they deviate from regular daily variability. To this end, we obtained functional magnetic resonance imaging data from 60 young, adult male participants, scanned in the morning and evening of the same day and again the following morning. 41 participants underwent total sleep deprivation before the third scan, whereas the remainder had another night of regular sleep. Sleep deprivation strongly altered the connectivity of several resting-state networks, including dorsal attention, default mode, and hippocampal networks. Multivariate classification based on connectivity profiles predicted deprivation state with high accuracy, corroborating the robustness of the findings on an individual level. Finally, correlation analysis suggested that morning-to-evening connectivity changes were reverted by sleep (control group)-a pattern which did not occur after deprivation. We conclude that both, a day of waking and a night of sleep deprivation dynamically alter the brain functional connectome.
I got an Oura ring a couple of years ago and have been working on improving my sleep and sleep habits ever since. For much of my adult life, I have been a poor sleeper. I have always been able to fall asleep quickly, but I have been plagued by two sleep issues. The first is waking up in the middle of the night and not being able to get back to sleep. The second is waking up early, like 4:30/5am, and being wide awake. So I’ve been working on those two things. I still wake up in the middle of t...
<em>Journal of Sleep Research</em> | ESRS Journal | Wiley Online Library
Napping is a cross-cultural phenomenon which occurs across the lifespan. People vary widely in the frequency with which they nap as well as the improvements in alertness and well-being experienced. T...
Opinion | Rethinking Sleep (Published 2012)
It’s not the quantity of sleep that restores and refreshes, but the quality.
Sleep deprivation is not a badge of honor
Forgoing sleep is like borrowing from a loan shark. Sure you get those extra hours right now to cover for your overly-optimistic estimation, but at what price? The shark will be back, and if you ca…
Insufficient Sleep Associated with Risky Teen Behavior
A new study reports teens who sleep for less than 6 hours per night are at greater risk of mental health issues, substance abuse, accidents and other risk taking behaviors.
How much can an extra hour's sleep change you?
The average Briton gets six-and-a-half hours sleep a night. Michael Mosley took part in an unusual experiment to see if this is enough.
Primary pupils 'need nine hours of sleep'
Primary school pupils need to have at least nine hours' sleep each night or their capacity to learn will be impaired, say researchers.
The myth of the eight-hour sleep
Sleeping in one eight-hour chunk is a very recent phenomenon, and lying awake at night could be good for you, according to scientists and historians.
Bad sleep 'dramatically' alters body
A run of poor sleep can have a dramatic effect on the internal workings of the human body, say UK researchers.
The 17th Century Guide to Sleep
Despite the modern obsession with a good night’s rest, more of us are sleeping less. Perhaps we should pay attention to the advice of early modern doctors.
