‘Night owls’ score consistently higher in cognitive tests compared to ‘morning people’, study finds!

Cat lovers and dog people, tea drinkers and coffee addicts, introverts and extroverts — few categories divide the internet and the world as these do, but one of them certainly is early birds vs night owls. Now, it appears bragging rights are in store for people of the night, as a new study suggests they might be cognitively sharper than their morning counterparts!

Indeed, a study delving into how sleep influences brain function has revealed that our preference for morning or evening activities — our chronotype, that is — can significantly impact cognitive performance. It found that ‘night owls’, or those who thrive in the evening, tend to score higher on cognitive tests compared to ‘morning larks’, who are most active early in the day. Turns out early birds might not get all the worms.
Cognitive curfew: Night owls, even ‘intermediates’ found to outshine the early birds
Researchers from Imperial College London analysed data from over 26,000 individuals to explore how different sleep aspects — duration, patterns and quality — affect mental sharpness and overall cognitive ability. Using information from the UK Biobank database, they assessed how self-identified morning or evening preferences influenced cognitive test results.

The findings were clear: evening types consistently outperformed their morning-oriented peers. Night owls scored about 13.5% higher in one test group and 7.5% higher in another. Even those with a moderate preference for either time — the ‘intermediate’ types — did better, with scores roughly 10.6% and 6.3% higher than morning larks in the respective groups.

These results were not only significant, but also adjusted for various health and lifestyle factors such as age, gender, smoking, alcohol consumption, and chronic conditions like heart disease and diabetes. The study underscores that the journey from night to day might be more than just a preference — it's a cognitive advantage.

However, it is important to note that this doesn't imply that all morning people perform poorly cognitively. The research simply highlights a trend indicating better cognition among the evening types.

The study also identified that optimal brain function is achieved with seven to nine hours of sleep per night, enhancing cognitive abilities like memory, reasoning and information processing speed. Conversely, sleeping fewer than seven or more than nine hours negatively impacted brain function.

Additionally, younger individuals and those without chronic conditions generally scored higher on cognitive tests, with healthier lifestyle choices correlating with better cognitive performance.

Interestingly, the researchers discovered that while sleep duration is crucial, individuals reporting insomnia did not score significantly lower in cognitive performance within their cohorts. This suggests that the severity and duration of insomnia need to be factored in to understand its full impact.

All in all, this exploration indicates that understanding and embracing our natural rhythms could be key to unlocking our full cognitive potential. Whether you're a night owl or a morning lark, fostering good sleep habits and a healthy lifestyle remains paramount for cognitive well-being.

The findings were recently published in BMJ Public Health and can be accessed here.