Broken sleep affects the ability to build memories, a study of mice suggests.
The Proceedings of the National Academy of Science findings could help explain memory problems linked to conditions including Alzheimer’s and sleep apnoea.
The Stanford University found disrupting sleep made it harder for the animals to recognise familiar objects.
A UK sleep expert said the brain used deep sleep to evaluate the day’s events and decide what to keep.
This study looked at sleep that was fragmented, but not shorter or less intense than normal for the mice.
It used a technique called optogenetics, where specific cells are genetically engineered so they can be controlled by light.
They targeted a type of brain cell that plays a key role in switching between the states of being asleep and being awake.
MOUSE MEMORY TEST
he researchers then sent light pulses directly into the brains of mice while they slept.
This meant they could disrupt their sleep without affecting total sleep time or the quality or composition of sleep.
The animals were then placed in a box with two objects, one of which they had encountered before.
Mice would naturally spend more time examining the newer object, and those who had been allowed uninterrupted sleep did just that.
But those whose sleep had been disrupted were equally interested in both objects, suggesting their memories had been affected.
Broken sleep also affects people addicted to alcohol, and those with sleep apnoea – a condition in which the throat repeatedly narrows or closes during sleep, restricting oxygen and causing the patient to wake up.
-With bbc.co.uk input