Night owls vs. early birds: Study reveals who has better cognitive function
Night owls will find this new research a hoot.
A study from Imperial College London suggests that those most active at night perform better on cognitive tests.
The researchers analyzed UK Biobank data from more than 26,000 people to see how sleep duration, patterns and quality affect mental acuity and cognitive capacity. Participants completed several tests and identified whether they felt more alert and productive in the morning or evening.
Researchers found that a person’s preference for p.m. or a.m. activity, also known as chronotype, greatly affected test scores. These chronotypes were designated “night owls” and “morning larks.”
En masse, owls outperformed their early-bird counterparts, with larks consistently exhibiting the lowest cognitive scores. Scores improved for “intermediate” types — respondents who expressed a mild preference for either day or night.
Owls scored 13.5% higher than larks in one group and 7.5% higher than them in another group. Intermediates scored 10.6% and 6.3% higher than morning types, according to findings published this week in BMJ Public Health.
Regarding lifestyle factors, younger folks and those without chronic conditions such as heart disease and diabetes tested better.
“Our study found that adults who are naturally more active in the evening (what we called ‘eveningness’) tended to perform better on cognitive tests than those who are ‘morning people,'” explained the study’s lead author, Dr. Raha West, who works in the Department of Surgery and Cancer at Imperial College London.
“Rather than just being personal preferences, these chronotypes could impact our cognitive function,” West continued.
So, should we all start hitting the hay a little later in the hopes of seeming smarter? Not necessarily.
“It’s important to note that this doesn’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,” West imparted.
“While it’s possible to shift your natural sleep habits by gradually adjusting your bedtime, increasing evening light exposure, and keeping a consistent sleep schedule, completely changing from a morning to an evening person is complex,” she added.
Jessica Chelekis, a senior lecturer in sustainability global value chains and sleep expert at Brunel University London, pointed out to the Guardian “important limitations” to the analysis, including it not accounting for educational achievement or the time of day participants took the tests.
Whether you identify as an owl or a lark, experts agree that sleeping seven to nine hours a night is optimal for brain function. This peak performance range is reflected in this new study, which found that a solid seven to nine hours of shuteye boosts memory, reasoning and information processing.
Inversely, sleeping less than seven hours or more than nine hours was shown to be detrimental to brain health.
“While understanding and working with your natural sleep tendencies is essential, it’s equally important to remember to get just enough sleep, not too long or too short,” West said. “This is crucial for keeping your brain healthy and functioning at its best.”
Interestingly, while sleep duration was found to be crucial to cognition, participants who reported symptoms of insomnia did not score significantly lower than others.
Researchers believe the severity and duration of symptoms need to be considered.
“We’ve found that sleep duration has a direct effect on brain function, and we believe that proactively managing sleep patterns is really important for boosting, and safeguarding, the way our brains work,” advised co-study leader Daqing Ma, a professor at Imperial’s Department of Surgery and Cancer.
“We’d ideally like to see policy interventions to help sleep patterns improve in the general population,” Ma said.
These findings linking late nights to better cognition challenge separate research that suggests being a night owl is harmful to mental health.
A study published in May in the journal Psychiatry Research found that hitting the hay before 1 a.m. lowers the risk of developing mental and behavioral conditions such as depression and anxiety.
Researchers believe the relationship between staying up late and poor mental health might owe itself to the “mind after midnight” hypothesis, which posits that being awake after midnight increases the likelihood of engaging in impulsive and harmful behaviors.
