Can humans become nocturnal?

Early risers and night owls really think differently

Some are just going to bed while the others are already putting on their jogging shoes for the refreshing morning run. The reason for this is not in the way of life, but in the brain.

Morning grouch or early riser: According to a study by Forschungszentrum Jülich, this can be recognized by the signal transmission in the white matter of the brain.

Photo: dpa

Do you also ask yourself during the days why you arrive at the office half sleepy while your colleague is already sitting in front of her computer, awake? We rummaged through our archives and found a scientific explanation for this phenomenon.

The white matter is to blame

A study by Forschungszentrum Jülich suggests that night owls and early risers really think differently. Scientifically speaking: The signal transmission in the white matter of the brain between these two types of people shows clear differences.

The Jülich scientists found this out in special examinations in the magnetic resonance tomograph. The white matter of the brain consists mainly of nerve fibers, which are primarily responsible for the transmission of information. Among other things, they ensure that we can speak and remember.

Tip: sleep in late

In the colored areas, the brains of early risers and night owls transmit signals to different degrees.

Source: Research Center Jülich

The researchers do not speak of “disruptions” - the processes are simply different. The night owl's internal clock, however, often collides with social conventions, such as prescribed working hours. This could be one reason why night owls are far more likely to experience depression than natural early risers and the normal chronotypes. They also smoke and drink more often. Incidentally, scientists divide people into chronotypes according to how their internal biological clock affects physical characteristics such as body temperature and performance. "The permanent sleep deficit of an extremely late chronotype can be compared to chronic jet lag," says Dr. Jessica Rosenberg from the Institute for Neuroscience and Medicine at FZ Jülich.

Some of those affected have probably already come up with the expert tip for compensating for this permanent jet lag, which the scientist quotes: Long sleep on days off. If you suffer from an extreme lack of sleep, additional professional light therapy could possibly help, says Rosenberg. This allows the individual sleeping and waking phases to be artificially shifted.

Night owls in search of recognition

More than 80 percent of people have a normal, i.e. healthy day-night rhythm. The rest describe themselves as either early risers or late sleepers - with the early risers being considered the happier people. In any case, many of them are very successful: Apple boss Tim Cook answers his emails in the early hours of the morning from 4:00 a.m., as he once revealed to Time magazine, Twitter co-founder Jack Dorsey uses the early hours to jog and Richard Branson enjoys enjoy the first rays of sun at breakfast. PepsiCo boss Indra Nooyi, on the other hand, said that she was up so early because she was suffering from insomnia.

Getting up early is a horror for many night owls. That is why some of them have organized themselves: The association “Delta T - Association for Second Normality eV” has existed in Germany for 20 years. The club “for late people and late sleepers” is a serious advocate for scientific research into the phenomenon - and for social acceptance . Because it is not just a question of goodwill to be fit in time in the morning. A view that supports the new Jülich study. The club's motto: "When the rooster crows on the dung, we are where it's nicer!"

In order to tackle the problem even more fundamentally, one more crucial question needs to be clarified: Are the differences in brain activity the cause or rather the consequence of the different sleep rhythms? There is currently no answer to this.

A contribution by:

  • Lisa Diez-wood

    The author was content manager for the TechnikKarriere-News-Portal of the VDI Verlag from 2017 to the end of 2019. Before that, she wrote for VDI nachrichten as an editor.

  • Werner Grosch