Being a 'night owl' might make your brain sharper

Individuals who stay up late proved to be more proficient in cognitive tests than those who wake up early, a study discovered. Nevertheless, this discovery does not necessitate that we all work through the night.

Do you identify as a "night owl" or a "morning lark" – someone who wakes early to tackle the day or someone who stays up late working? Whatever it may be, consider it your "chronotype".

There is evidence to suggest that an individual's chronotype has an impact on their overall cognitive abilities. The study found that those who stay up late, or night owls, tend to score higher in cognitive skills compared to those who are early risers, or morning larks.

Based on insights from over 26,000 individuals who completed various cognitive assessments.

The objective was to discover how various aspects of sleep, such as duration, patterns, and quality, impact mental sharpness and overall cognitive function.

The research, known as the "night owl" study, suggests that individuals who stay up late and wake up late may start their biological clocks a bit behind schedule. They tend to experience a natural dip in alertness, or circadian rhythm, later in the evening.

It was ideal for brain function, but they also found that a person's sleep timing preference impacted their test results.

"Adults who [were] naturally more active in the evening tended to perform better on cognitive tests than those who [were] 'morning people,'" said lead author Raha West, Imperial College London, UK, in a press statement. "Rather than just being personal preferences, these chronotypes could impact our cognitive function."

But that didn't mean all morning people have worse cognitive performance. "The findings reflect an overall trend where the majority might lean towards better cognition in the evening types," said West.

What's more, your chronotype is not set in stone — you can adapt, either way. And simply getting a good night's sleep can improve your cognitive performance, too.

The science of sleep chronotypes

Chronotypes are not permanent — they can shift over our lifetimes.

"Children tend to be morning types, adolescents and young adults shift towards being evening types, and older adults often revert to being morning types," said Feifei Wang, a sleep expert at Eötvös Loránd University in Budapest, Hungary.

.

"A combination of genetic, hormonal, environmental, and lifestyle factors determines whether a person is more active in the morning or evening, and these factors interact to shape an individual's chronotype," said Wang, who was not part of the new study.

Chronotypes are partly related to differences in our circadian rhythms — the body's biological clock, which runs essential functions, such as sleep and metabolism.

Genes involved in a person's circadian rhythm, include genes called "CLOCK", "PER", "CRY". They have a strong impact on chronotype. They "influence whether a person is a morning or evening type," Wang told Weden News.

But you can train yourself to be a morning or evening type.

"We've shown undergraduate students can advance their chronotype by almost two hours over two years," said Ignacio Estevan, a sleep expert at Universidad de la República in Montevideo, Uruguay. Estevan was also not involved in the new study.

'All-nighters' reduce academic test performance

Estevan has researched the association between chronotypes and school grades. He has found that test performance in night owls and morning larks depended on when during the day you tested them for your study.

"We found that late chronotypes had worse academic performance compared to early chronotypes in the morning shift, and not in the afternoon shift," Estevan told Weden News, adding that his research contributed to a body of evidence showing that school start-times have an impact on children's academic performance.

Some experts argue that better alignment between school timing and students' biological rhythms would enhance their opportunities later in life.

. Studies tend to show that people who sleep longer perform better in tests.

Estevan said that can be explained by the importance of sleep for learning and good cognitive functioning. His research has found that doing an 'all-nighter' to revise last-minute has a bad effect on test scores.

"Around 15% of the students [in our study] did not sleep before the test, and they had the worst performance," said Estevan.

So, what's the best way to get a good night's sleep? Wang recommended keeping "a regular sleep schedule, have a dark and quiet environment to sleep in, try to relax, do not consume caffeine or stimulants after nightfall, and reduce exposure to light at night, particularly before going to sleep."

Edited by: Zulfikar Abbany

Primary source:

https://doi.org/10.1136/bmjph-2024-001000

Author: Fred Schwaller