Chronic insomnia may be linked to a disruption in a person's internal biological clock, causing the brain to continue working even when the body should be resting, according to researchers from the University of South Australia, whose research is published in the journal Sleep Medicine.
Researchers have found that people with insomnia have disrupted circadian rhythms—the natural daily cycles that regulate sleep and wakefulness—which explains the common feeling of constant “mental noise,” where thoughts remain active even at night.
As part of the study, scientists analyzed the cognitive activity of 32 participants. Half of them were diagnosed with chronic insomnia, the other had a normal sleep pattern. It turned out that the brains of people with sleep disorders do not enter a state of so-called “night silence”. The peak of mental activity in such people is shifted by about 6.5 hours, so the brain actually continues to work in the daytime mode.
Lead author of the study, Professor Kurt Lushington, explained that sleep is not just physical rest, but primarily the brain's ability to reduce the level of purposeful thinking and emotional activity. In people with insomnia, this mechanism of transition between states is disrupted.
The researchers say future treatments may not only focus on changing sleep behaviors, but also on restoring circadian rhythms. Possible approaches include controlling light exposure during the day, maintaining a consistent sleep schedule, and practicing mindfulness and meditation to help reduce brain activity before bedtime.
Experts estimate that insomnia affects about 10% of the world's population, and among the elderly, the problem can affect up to a third of the population. New research findings help to better understand the biological causes of sleep disorders and open up possibilities for more effective treatments.
