The disruption of circadian rhythms can cause accelerated neurodegeneration, loss of motor function and premature death, it has been found.
Researchers at Oregon State University have confirmed that disruption to circadian rhythms - or biological clock - causes neurodegeneration.
Although the study was done on fruit flies, previous research has indicated that there are close parallels between them and humans.
The fruit flies carried two mutations, one that disrupts circadian rhythms and another that causes flies to develop brain pathologies during aging.
Researchers found that those with double mutants had a 32-50 per cent shorter lifespan, lost much of their motor function, and developed significant "vacuoles", or holes in their brains, far sooner than flies without circadian rhythm disruption.
Jadwiga Giebultowicz, project leader, commented: "When the biological clock begins to fail, rhythms that regulate cell function and health get disrupted, and we now know that this predisposes the brain to neurodegeneration."
Depression has also been linked to disturbances in the biological clock.
Scientists examined genes that regulate circadian rhythm in people with and without a history of depression and those with a higher level of activity had were found to be at greater risk of depression.
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