Emerging research suggests that consistently working long hours may physically reshape the brain, particularly in regions responsible for emotional control and high-level cognitive functions like decision-making and memory.
A team of researchers examined brain scans from healthcare professionals, aiming to uncover potential neurological effects tied to extended work schedules.
Their early findings, published in Occupational & Environmental Medicine, point to notable differences in brain structure between those working standard hours and those exceeding 52 hours per week.
The study involved participants from the Gachon Regional Occupational Cohort Study, with a final analysis of 110 individuals, most of whom were clinicians.
Brain scans revealed that those regularly clocking longer hours showed significant volume increases in several key brain regions.
Among the most affected was the middle frontal gyrus, a critical area for attention, memory, and language processing. This group exhibited a 19% increase in volume in that area compared to peers working standard hours.
Researchers also used advanced imaging techniques to observe changes in other parts of the brain, including the superior frontal gyrus — linked to planning and decision-making — and the insula, which plays a central role in emotional awareness and social perception.
While the health risks of overwork — such as heart disease and mental health challenges — are well-established, its impact on brain anatomy is still being explored.
This study provides early evidence that excessive working hours may lead to neurological adaptations, though whether these changes are harmful or compensatory remains unclear.
Importantly, this was a small observational study, and the researchers caution against drawing definitive conclusions. Without long-term follow-up, it’s uncertain whether the observed brain differences are a result of overwork or whether individuals predisposed to such brain patterns are more likely to take on demanding schedules.
Nonetheless, the findings contribute to a growing body of evidence highlighting the potential costs of chronic overwork, not just to physical and mental health, but possibly to brain structure itself.
The authors said: “While the results should be interpreted cautiously due to the exploratory nature of this pilot study, they represent a meaningful first step in understanding the relationship between overwork and brain health.
“Notably, the increased brain volumes observed in overworked individuals may reflect neuroadaptive responses to chronic occupational stress, although the exact mechanisms remain speculative.”
They continued: “The observed changes in brain volume may provide a biological basis for the cognitive and emotional challenges often reported in overworked individuals.
“Future longitudinal and multi-modal neuroimaging studies are warranted to confirm these findings and elucidate the underlying mechanisms.”
They concluded: “The results underscore the importance of addressing overwork as an occupational health concern and highlight the need for workplace policies that mitigate excessive working hours.”
The study has been published in the journal Occupational and Environmental Medicine.
