A study by Stanford University in the United States found that when the animals' sleep was disrupted, they would have found it harder to recognize familiar objects. A British sleep expert believes that the brain uses deep sleep to assess what happened during the day and decide what needs to be preserved. Researchers used optogenetic techniques to genetically modify some of the cells so that they could be manipulated with light. They then locked in a brain cell that was crucial to the sleep-wake transition.
In the experiment, researchers used light pulses to directly affect the brain of sleeping rats. So they can disturb the mouse's sleep, and will not affect the overall sleep time and quality of sleep.
The mice were then placed in a box containing two objects, one of which was previously recognized by them. Normal mice spend more time examining new objects. But mice that were disturbed by sleep showed the same interest in both things, implying that their memory was affected to some degree.
Broken sleep can also bother obsessing with alcohol and people with sleep apnea. There is evidence that sleep apnea patients have some problems with memory formation. People with Alzheimer's also commonly have sleep problems, but it is not yet clear whether the deterioration of the brain leads to poor sleep or poor sleep leading to brain degeneration.
Miranda Watson, head of communications at the British Lung Foundation, said: "This intermittent sleep may lead to very tired during the day and cause memory loss."