Night owls exhibit better cognition, new research suggests. The study found that people who prefer to stay and wake up late tended to perform better on cognitive tests than early birds. Getting a decent amount of sleep was also associated with better cognition.
The research, conducted by scientists from Imperial College London in the UK, aimed to explore the relationship between different aspects of sleep and mental performance, including a person’s preferred sleep time, or chronotype. Our chronotype runs along a spectrum, with early birds preferring to sleep and wake up early and night owls preferring a late night and late morning rise.
Examining sleep and cognition
The research team analyzed data from the UK Biobank, a longstanding research project that has followed UK residents’ health for many years. As part of the project, researchers asked volunteers to undergo various tests and fill out questionnaires about their daily habits, including sleep. The researchers split the analysis into two parts: they examined data from volunteers who had completed all four cognitive tests included in the project and those who completed two specific tests that assessed their memory and reaction time.
All told, the team examined data from over 26,000 participants ages 53 to 86, finding several links between sleep and better cognitive functioning. Those who reported sleeping the typical amount recommended, around seven to nine hours a night, tended to do better on cognitive tests than those who didn’t, for instance. But the researchers also found that self-reported night owls exhibit better cognition compared to early birds, as did people somewhere in the middle.
“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,’” said lead author Raha West, a researcher at ICL’s Department of Surgery and Cancer, in a statement from the university. “Rather than just being personal preferences, these chronotypes could impact our cognitive function.”
Correlation doesn’t imply causation
The team’s findings, published this week in the journal BMJ Public Health, can show only a correlation between being a night owl and better mental sharpness, not definitively prove it. And even if this was the case, there are other potential disadvantages to being an evening person. Night owls who work or go to school early are more likely to experience social jetlag, for instance, meaning they can’t often get the amount or kind of sleep they prefer—a discrepancy that can cause subtle but noticeable long-term harm to a person’s metabolism and overall health. Night owls in general may also be at higher risk for health issues like diabetes.
The researchers say their work demonstrates that the relationship between our brain and sleep is nuanced and complicated. But at the very least, it seems that trying to ensure that we get as much sleep as we need, ideally when we prefer it, is key to keeping our minds sharp.
“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,” said West. “This is crucial for keeping your brain healthy and functioning at its best.”