Poor grades tied to class times that don't match our biological clocks

March 29, 2018 by Yasmin Anwar, University of California - Berkeley
Poor grades tied to class times that don't match our biological clocks
Owls performed worst of all the groups due to chronic social jet lag. Credit: Benjamin Smarr

It may be time to tailor students' class schedules to their natural biological rhythms, according to a new study from UC Berkeley and Northeastern Illinois University.

Researchers tracked the personal daily online activity profiles of nearly 15,000 college students as they logged into campus servers.

After sorting the students into "night owls," "daytime finches" and "morning larks"—based on their activities on days they were not in class—researchers compared their class times to their academic outcomes.

Their findings, published today in the journal Scientific Reports, show that students whose were out of sync with their - say, night owls taking early morning courses - received lower grades due to "social jet lag," a condition in which peak alertness times are at odds with work, school or other demands.

"We found that the majority of students were being jet-lagged by their class times, which correlated very strongly with decreased academic performance," said study co-lead author Benjamin Smarr, a postdoctoral fellow who studies circadian rhythm disruptions in the lab of UC Berkeley psychology professor Lance Kriegsfeld.

In addition to learning deficits, social jet lag has been tied to obesity and excessive alcohol and tobacco use.

On a positive note: "Our research indicates that if a student can structure a consistent schedule in which class days resemble non-class days, they are more likely to achieve academic success," said study co-lead author Aaron Schirmer, an associate professor of biology at Northeastern Illinois University.

While students of all categories suffered from class-induced jet lag, the study found that night owls were especially vulnerable, many appearing so chronically jet-lagged that they were unable to perform optimally at any of day.But it's not as simple as students just staying up too late, Smarr said

Poor grades tied to class times that don't match our biological clocks
Trajectory on left tracks performance (GPA) of students whose alertness peaks before class times while the right side tracks performance of students whose alertness peaks after class times. Credit: Benjamin Smarr
"Because owls are later and classes tend to be earlier, this mismatch hits owls the hardest, but we see larks and finches taking later classes and also suffering from the mismatch," said Smarr. "Different people really do have biologically diverse timing, so there isn't a one-time-fits-all solution for education."

In what is thought to be the largest-ever survey of using real-world data, Smarr and Schirmer analyzed the online activity of 14,894 Northeastern Illinois University students as they logged in and out of the campus's learning management system over two years.

To separate the owls from the larks from the finches, and gain a more accurate alertness profile, the researchers tracked students' activity levels on days that they did not attend a class.

Next, they looked at how larks, finches and owls had scheduled their classes during four semesters from 2014 to 2016 and found that about 40 percent were mostly biologically in sync with their class times. As a result, they performed better in and enjoyed higher GPAs.

However, 50 percent of the students were taking classes before they were fully alert, and another 10 percent had already peaked by the time their classes started.

Previous studies have found that older people tend to be active earlier while young adults shift to a later sleep-wake cycle during puberty. Overall, men stay up later than women, and circadian rhythms shift with the seasons based on natural light.

Finding these patterns reflected in students' login data spurred researchers to investigate whether digital records might also reflect the underlying people's behavior.

The results suggest that "rather than admonish late students to go to bed earlier, in conflict with their biological rhythms, we should work to individualize education so that learning and classes are structured to take advantage of knowing what time of day a given will be most capable of learning," Smarr said.

Explore further: New doctors' intense and changing schedules take a toll on sleep, activity and mood

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1 / 5 (2) Mar 29, 2018
This study is mostly hogwash. Yes, if we would be exposed to the right light when we woke up, and go to sleep when it was dark, and allow ourselves these luxuries, it would be better for us. Nice light to wake up to and nice darkness or redder light to guide us to drowsiness, that would be great, but arbitrarily changing start times is a waste of time. Yes trying to mimic natural life has some merit, but it would be better if we just went to incandescent light bulbs which give us a more natural exposure. Of course the people who wrote this study are violently against more carbon dioxide to use the old lights and will come up with some crazy ideas to make life even more complicated.
1 / 5 (1) Mar 30, 2018
Any opposition to C02 at this point is a waste of time. The damage done is now irreversible.

Excepting environmental toxins, etc., the real cause for lousy grades is lousy parents. End of story.
not rated yet Mar 30, 2018
If the students in China and India can get top grades year after year then it is time to stop making excuses for US students with poor marks. You will get many achieving top marks when you stop this nonsense about 'leaving no pupil behind.' No incentive when all students get 'top marks' for no effort.
3 / 5 (4) Mar 30, 2018
Are you three just paid to troll science articles or do you spend your entire lives waiting for new stuff to get posted, just for fun?
2.3 / 5 (3) Mar 31, 2018
Can't speak for the others, but I troll science articles to learn, not to waste time with vacuous questions like yours, PTTG. You post commentary of no value because you cannot think of things worthy of discussion. Try some of the children's sites and learn about worms and frogs.

You have added nothing to the thread but proof of your poor education.

Your parents must have failed you too.

Worthless posters like you should be banned from the site.

There is no intelligent life here.

Happy trails........

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