Rest and sleep are vital for brain health. New research suggests the brain uses downtime to consolidate memories, or transfer recent memories from one part of the brain to another -- to back up its hard drive, so to speak.

The findings are the result of tests involving lab rats, but the revelation could have implications for Alzheimer's research. Scientists say an improved understanding of the memory formation and storage process may reveal how Alzheimer's disrupts memory consolidation.

To watch memory consolidation in real time, scientists at the University of College London monitored brain activity in rats during and after their time spent on a running track. Specifically, researchers monitored two parts of the brain key in memory formation and storage, the hippocampus and the entorhinal cortex.

As part of the experiment, rats spent 30 minutes running on a track and 90 minutes resting. Brain activity revealed short-term memory formation while running. When the rats were allowed to rest, the memory of their run was replayed or reactivated in their brain at 10 to 20 times the speed of the actual experience.

Brain monitoring showed the replay was happening in two parts of the brain, almost simultaneously, with just a 10-millisecond delay. The revelation suggests the brain transfers newly formed memories during rest.

"This is the first time we've seen coordinated replay between two areas of the brain known to be important for memory, suggesting a filing of memories from one area to another," study author

Caswell Barry, a developmental biologist at UCL, said in a news release. "The hippocampus constantly absorbs information but it seems it can't store everything so replays the important memories for long term storage and transfers them to the entorhinal cortex, and possibly on to other areas of the brain, for safe-keeping and easy access."

The new research was detailed this week in the journal Nature Neuroscience.