May 17, 2025, 12:06 pm | Read time: 4 minutes
Do you sometimes feel like your head is spinning after a long and exhausting day? This might be more than just a common expression. A study found that prolonged stress from spending too much time at work can lead to significant structural changes in the brain. Learn more about it at FITBOOK.
Work doesn’t automatically mean stress. But it can. FITBOOK reported on a study that showed how the way someone types on a computer or moves a mouse can reveal their stress level.1 After all, the World Health Organization (WHO) defines burnout as a “syndrome resulting from chronic workplace stress.”2 It’s now scientifically proven that this burnout syndrome can lead to changes in the brain.3 However, damage might not only occur when illness sets in but could start with excessive time at work. A Korean study examining the effect of overtime on brain structure suggests just that.4
Overview
Study on the Effect of Overtime on the Brain
Behavioral and psychological consequences of overwork are now well-documented, the authors write in their study introduction. However, little is known about the immediate effects of this form of stress on brain structure. The study aimed to provide neurobiological data on the impact of long working hours for the first time.
The study involved 110 participants from Korea, mostly employed in the health sector. Thirty-two of them regularly worked more than 52 hours per week, often doing overtime. The remaining participants (control group) generally had normal working hours. All participants underwent magnetic resonance imaging (MRI) to identify possible structural differences in the brain.
Increased Brain Volume Due to More Work Hours
The overtime group showed significant changes in certain brain regions. Among other things, the researchers found an increased volume in the middle frontal lobe in participants who frequently worked more than 52 hours per week—by about 19 percent in some cases. This area in the front part of the brain is important for central cognitive processes (such as decision-making) and the regulation of behavior and emotions. Additionally, enlargements were observed in brain regions associated with executive functions.
At first, this might sound like favorable changes. After all, brain atrophy—meaning the loss of brain mass—is considered problematic because it can lead to neurological deficits and permanent loss of cognitive abilities. However, the reverse does not automatically mean that an increase in brain mass is positive. This is how the study authors interpret it. Long working hours could trigger neuroadaptive changes that might affect cognitive and emotional health.
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Significance of the Results and Limitations
The authors do not make a definitive statement about whether the observed brain changes are positive adaptations or harmful effects. It also remains unclear whether the changes are permanent or only temporary. Nevertheless, the results are remarkable: For the first time, it is shown that work—specifically overtime and its extent—can measurably affect brain structure. The study raises important political, occupational health, and societal questions. It could prompt a reevaluation of existing worktime regulations to better protect mental health in the long term. However, it is also clear that much more research is needed to truly understand the connections.
Some limitations should be noted. The study was a pilot and cross-sectional study, which does not allow for reliable statements about long-term developments or causal relationships. The relatively small number of participants also makes it difficult to generalize the results to the entire population. Additionally, since the participants were mostly from the healthcare sector, it remains unclear whether the observations can be applied to other occupational groups.