Why Morning People Shouldn't Work Night Jobs

While it is well-documented that morning people tend to work less efficiently at night than do night owls, the exact reasons for this have remained unclear. Now a new study by researchers at the National Research University Higher School of Economics in Russia and Oxford University in England reveals distinct differences between the thought processes of both morning people and night owls as they work on tasks at night.

The findings show that morning people who work at night appear to finish tasks more quickly than night owls, but they also tend to make more mistakes overall. On the other hand, night owls tend to work more slowly at night but demonstrate greater overall accuracy.

For the study, researchers Nicola Barclay and Andriy Myachykov investigated the influence of sleep deprivation on people with different chronotypes (behavioral differences due to circadian rhythms). Specifically, the researchers wanted to determine how an increase in time spent awake affects the attention system of early risers and night owls.

The study involved 26 participants (13 male, 13 female) with an average age of 25. The subjects were required to stay awake for 18 hours, from 8:00 a.m. to 2:00 a.m., and adhere to their normal routine. At the beginning and end of their time spent awake, the participants completed an Attention Network Test (ANT) as well as a questionnaire to help assess their chronotype.

The researchers did not find any significant differences between the scores of early birds and night owls on the ANT test completed in the morning, but the evening test showed a more pronounced contrast.

The early birds completed tests more quickly than did the night owls, which was a rather surprising and seemingly contradictory outcome, although the researchers did find an explanation for this.

They suggest that this can be explained by the way each group approaches the task. For example, night owls tended to take a more serious approach when it came to tasks requiring more time and attention during their favorite hours, i.e., in the late evening or at night.

“To deal with the most difficult test — resolving a conflict of attention — it was necessary not only to concentrate on the main visual stimulus, but at the same time to ignore accompanying stimulus that distract from the core task,” said Myachykov.

Completion of this task requires increased concentration. “An interesting fact is that although night owls spent more time finishing than early birds, their accuracy in completing the task was higher,” he said.

Overall, the evening people turned out to be slower but more efficient compared to the morning people, according to the second ANT taken at 2:00 a.m. after 18 hours of being awake.

“On the one hand, it’s known that night owls are more efficient in the late hours, but how this influences the speed and accuracy with which attention-related tasks are completed remains unclear. Our study demonstrated how night owls working late at night “sacrifice” speed for accuracy,” said Myachykov.

The new findings could be very useful for people who work the night shift, particularly those who depend on large doses of attention, concentration, and reaction time, such as pilots, air traffic controllers, and drivers.

The study is published in the journal Experimental Brain Research.

Source: National Research University Higher School of Economics