Scientists have discovered how long-term work affects the brain

They say work kills horses. And now, for the first time, it has been documented that long working hours can cause structural changes in the brain, particularly in areas responsible for emotional regulation and executive functions such as working memory, attention and decision-making. These findings raise serious concerns among scientists about the long-term consequences of chronic fatigue and highlight the need to review work standards and occupational health policies.

A South Korean study used neuroimaging techniques — specifically MRI scans — to assess structural changes in the brains of workers who regularly work more than 52 hours a week. The study involved 110 people, most of whom work intense schedules, and a control group who worked standard hours.

The results showed that those who worked longer hours showed significant changes in areas of the brain associated with cognitive and emotional functions. In particular, they showed an increase in the volume of the middle frontal gyrus by about 19 percent. Let’s explain: this part of the brain plays a key role in attention, working memory, planning and decision-making. The analysis also revealed an increase in the superior frontal gyrus and insular area – structures responsible for integrating sensory data, processing emotions and social perception.

Interestingly, the increase in brain volume in overtired participants may indicate neuroadaptive responses to chronic stress and fatigue. However, the scientists emphasize that these changes are not necessarily positive: they may reflect compensatory mechanisms or signs of the initial stages of neural adaptations that in the long term can lead to cognitive and emotional impairment.

“This is the first study to show that long working hours can affect brain structure,” says researcher David Palomino. “While we can’t say for sure whether these changes are due to fatigue or predisposition, the results highlight the need for more research into this issue and the potential health risks for workers.”

The International Labour Organization (ILO) estimates that over 800,000 people die each year from overwork. In most countries, working hours exceed established standards, raising concerns about long-term health consequences. In particular, overwork is known to be associated with an increased risk of cardiovascular disease, metabolic disorders and mental disorders.

The authors of the study emphasize that further work is needed to understand how structural changes relate to cognitive and emotional impairments, and to determine whether they are reversible with reduced workload and improved working conditions. Future work will involve using more precise neuroimaging methods and analyzing the influence of factors such as stress levels, sleep quality, nutrition, and physical activity.

Authors: