A study shows that when we are tired, we become even more aggressive

Mental fatigue can make us more aggressive and less cooperative, according to a new study by Italian researchers, published in the Proceedings of the National Academy of Sciences.

The research team, led by Erica Ordali, did a large experiment with more than 400 participants, divided into two groups. The first group was subjected to exhausting activities before the tests, while the second group came rested.

The rate of peaceful cooperation dropped from 86% to only 41% for tired people. The exhausted participants became much more hostile and less willing to share resources, and the areas of the brain responsible for making decisions began to show signs of “falling asleep” while the person was still awake.

“It’s like this vital part of the brain shuts down”

To confirm the findings, the researchers did a second experiment with 44 people, using electroencephalogram (EEG). They observed a fascinating phenomenon called “local sleep” – certain areas of the brain, especially the frontal cortex responsible for decision-making, began to emit brain waves specific to sleep, even if the person was awake.

“It’s as if this vital part of the brain shuts down when we’re tired, even though we’re still awake,” the researchers explain.

The advice from those who did the research, for important negotiations and decisions, is to schedule meetings in the morning when you are rested, avoid important negotiations in the late afternoon.
If you feel tired, better postpone for the next day.

In everyday life, regular breaks are essential to maintain decision-making ability. Fatigue can also negatively affect personal and professional relationships.

Professor Pietro Pietrini, co-author of the study, points out: “Our findings have important implications for multiple situations in everyday life, from economic transactions to legal agreements. When the brain is we can make decisions even against our interests”.

The study also has implications for the educational system (the importance of breaks in the learning process), mediation and conflict resolution, understanding aggressive behavior in society or improving interpersonal relationships.