Brain Differences Could Explain Why Night Owls Struggle With The 9-to-5 Grind


Rachel Baxter

Copy Editor & Staff Writer



Do you struggle to get up for work in the morning but then find yourself wide awake at 3am falling down a YouTube rabbit hole? Well, it sounds like you’re a night owl and, according to a new study published in the journal Sleep, your brain literally differs from that of the so-called morning lark, that person who’s annoyingly sprightly at 7am.

If you wanted an excuse to suggest flexible hours to your boss, this new study might just be the evidence you were looking for.


An international team of scientists, led by the University of Birmingham in the UK, discovered that night owls have reduced connectivity in brain regions linked to consciousness, meaning that during normal working hours they are hindered by sleepiness, a lack of attention, and slower reaction times.

Roughly half of people identify as night owls, meaning they naturally prefer to go to bed late and get up after 8.20am. The daily grind of 9 to 5 can actually act as a kind of jet lag for late risers, forcing them to go against their body's natural clock.

“A huge number of people struggle to deliver their best performance during work or school hours they are not naturally suited to,” lead researcher Dr Elise Facer-Childs said in a statement. “There is a critical need to increase our understanding of these issues in order to minimise health risks in society, as well as maximise productivity.”

The team recruited 38 volunteers (it’s important to note this is a pretty small sample size) and determined whether they were night owls or morning larks based on their sleep/wake cycles, biological rhythms, and answers to questionnaires. They were then subjected to MRI scans before completing tasks at various points during the day. They also reported how sleepy they felt.


Unsurprisingly, the researchers found that morning larks were less sleepy and had faster reaction times in the early morning. Meanwhile, night owls were at their best at 8pm and at their worst early on in the day. Interestingly, the night owls didn’t perform significantly better than the morning larks at 8pm, suggesting that society’s hours might be having a detrimental effect on those who prefer to wake up late.  

When the researchers looked at their participants’ brain activity, they found that connectivity in regions that predict better performance and reduced sleepiness was much higher in the brains of early risers. This suggests that night owls’ brain connectivity is impaired all day, from 8am to 8pm.

“This mismatch between a person’s biological time and social time – which most of us have experienced in the form of jet lag – is a common issue for night owls trying to follow a normal working day,” explained Facer-Childs. “Our study is the first to show a potential intrinsic neuronal mechanism behind why ‘night owls’ may face cognitive disadvantages when being forced to fit into these constraints.

“To manage this, we need to get better at taking an individual’s personal body clock into account – particularly in the world of work. A typical day might last from 9am-5pm, but for a night owl, this could result in diminished performance during the morning, lower brain connectivity in regions linked to consciousness and increased daytime sleepiness. If, as a society, we could be more flexible about how we manage time we could go a long way towards maximising productivity and minimising health risks.”