A recent study reveals that staying awake for 24 hours can significantly impair blood flow regulation in the brain, pointing to potential health risks related to sleep deprivation. Conducted by researchers and published on March 19, 2025, the investigation involved 25 healthy adults, examining how a night without sleep affects cerebral blood flow in vital arteries responsible for delivering nutrients and oxygen to the brain.
The study specifically highlighted the posterior cerebral artery (PCA) and middle cerebral artery (MCA), assessing flow velocities in both arteries before and after the participants underwent a full day of sleep deprivation. It also looked at the visually evoked flow velocity response in the PCA, which is indicative of neurovascular coupling—the brain's ability to increase blood flow in response to neuronal activity—and the hypercapnia-induced flow response in the MCA, showing how the vessels react to increased carbon dioxide levels in the blood.
Using advanced techniques such as transcranial Doppler ultrasound and visual evoked potentials, researchers monitored changes in blood flow dynamics. Their findings reported a tendency toward increased resting flow velocities in both the PCA (p = 0.08) and MCA (p = 0.07) after 24 hours of no sleep. However, the study also demonstrated significant reductions in both the visually evoked flow responses in the PCA and the hypercapnia-induced flow increases in the MCA after sleep deprivation.
The authors noted that visual evoked potential amplitudes did not change between the two assessment points, suggesting that the observed reductions in blood flow responses were not due to decreases in neuronal activation. Instead, they proposed a decreased vasodilatory response as the likely culprit for the hindered functional stimulation-evoked response. The study concluded that sleep deprivation could indeed impair essential cerebral blood flow regulation, which is crucial for maintaining cognitive and physical health.
This new research underscores the increasingly recognized health implications of chronic sleep deprivation—a condition that affects nearly one-third of U.S. adults. Experts emphasize that maintaining adequate sleep is vital not only for cognitive function but also for effective brain blood flow management, which can have long-term consequences for cardiovascular health and neural function.
The study's findings contribute to a growing body of literature addressing the relationship between sleep quality and vascular health. Given the evidence linking sleep deprivation with various health risks—including obesity, hypertension, and cerebrovascular diseases—prioritizing adequate sleep should be considered essential for overall health.
This research was endorsed by the Hungarian National Brain Research Program and emphasizes the need for further studies to explore the long-term effects of sleep deprivation on cerebral vascular health and cognitive performance.
