BBC News Report
Thursday, March 27, 2014
A new study published in The Journal of Neuroscience suggests that sleep loss may be more serious than previously thought, causing permanent loss of brain cells.
Researchers looked at lab mice that were kept awake to replicate the kind of sleep loss common in contemporary life, through night shifts or long hours at work.
The University of Pennsylvania School of Medicine team studied certain brain cells which are involved in keeping the brain alert.
After several days of sleep patterns similar to those followed by night workers – three days of night shifts with only four to five hours sleep in 24 hours – the mice lost 25 percent of the brain cells in part of the brain stem.
The scientists say this is the first evidence that sleep loss can lead to a loss of brain cells.
They nevertheless add that more work needs to be done to find out if people who miss out on sleep might also be at risk of permanent damage.
"We now have evidence that sleep loss can lead to irreversible injury," Professor Sigrid Veasey of the Center for Sleep and Circadian Neurobiology told BBC News. "This might be in a simple animal but this suggests to us that we are going to have to look very carefully in humans."
Professor Veasey said the next step was to examine the brains of shift workers after death for evidence of any loss of brain cells.
Professor Hugh Piggins of the University of Manchester said the experiment in mice indicated what might go wrong in the human brain.
"The authors draw parallels with night shift work in humans and suggest how chronic sleep deprivation could adversely affect not only our physical, but also our mental health," he said.
"This possibility will need to be tested by a lot more research. Nonetheless, it is consistent with many recent reports of importance of circadian clocks and sleep cycles for optimal well-being.
