You probably know whether you're a morning or night person. Now science has some good news for the early risers: Apparently the early bird really does get the worm.
There are fundamental differences in brain function between night owls and early birds, and night owls may have impaired function during regular work-day hours, according to a new study published Thursday in the academic journal "Sleep."
Researchers at the University of Birmingham looked at the brain function (among other things) of 38 people who were categorized as either night owls, who had an average bedtime of 2:30 a.m. and a wake-up time of 10:00 a.m., or morning larks, who had average bedtime of 11 p.m. and wake time of 6:30 a.m.
Participants underwent MRI scans, were asked to complete a series of tasks and participated in testing sessions at different times during the day between 8 a.m. and 8 p.m., while also being asked to report their level of sleepiness.
Overall, researchers found that night owls had lower resting brain connectivity in ways that are associated with poorer attention, slower reactions and increased sleepiness throughout the hours of a typical work day.
Meanwhile, brain connectivity in the regions of the brain that can predict better performance and lower sleepiness were significantly higher in larks at all times, "suggesting that the resting state brain connectivity of night owls is impaired throughout the whole day." (The "resting state" of the brain, Live Science notes, means not doing a particular task and letting the mind wander.)
"A huge number of people struggle to deliver their best performance during work or school hours they are not naturally suited to," says the study's lead researcher, Dr. Elise Facer-Childs, of the University of Birmingham's Centre for Human Brain Health. "There is a critical need to increase our understanding of these issues in order to minimize health risks in society, as well as maximize productivity."
And whether you're a morning or night person might be dictated by your genes. A separate study published in January looked at the genomes of almost 700,000 people, using data from 23andMe and the U.K. Biobank. It found that there are hundreds of genes that are associated with whether you are a night owl or an early bird. Regions of the genome that the study found to be relevant to whether you're a morning or night person included genes involved in metabolism, the biological clock and genes that function in the retina.
However, knowing whether you're an early bird, night owl or somewhere in between can help you optimize your productivity throughout the day, according to Daniel Pink, author of "When: The Scientific Secrets of Perfect Timing."
"All times of day are not created equal," Pink previously told CNBC Make It. "Our performance varies considerably over the course of the day, and what task to do at a certain time really depends on the nature of the task. If we look at the evidence, we can be doing the right work, at the right time."
According to Pink, for larks, the morning is the best time to do analytical work that requires focus, and more administrative or routine work should be done later in the day. The reverse is true for night owls.
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