Some people seem able to function on very little sleep while others struggle after a sleepless night. Previous research has shown that a gene called PERIOD3 (PER3 for short) affects people's ability to cope with sleep deprivation. People with one variation of the gene are resilient to sleep loss and perform well on cognitive tasks after sleep deprivation, whereas people with the other variation perform more poorly. Researchers from the University of Liege in Belgium and the University of Surrey in the U.K. compared participants in their study with the resilient version of the gene to those with the other version, scanning their brains while they performed a memory task. Each participant was imaged four times: the night before and the morning after a good night's sleep and the night before and the morning after a bad night's sleep. The researchers found that the participants with the resilient gene were able to use other parts of their brains (as well as the ones normally expected to be used in the task) as they worked on the task whereas those with the less resilient version showed reduced activity in the brain structures normally activated by the task with no help from elsewhere in the brain. The people with the less resilient gene also performed worse even after a good night's sleep suggesting that people with this gene variation take a bit of time to get going in the morning.
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