How sleep and memory go hand-in-hand

Finding a new co-relationship between sleep and memory, a new study on flies has discovered that sleep, memory and learning are deeply connected.

When dorsal paired medial (DPM) neurons, well known memory consolidators in Drosophila, were activated, the flies slept more; when deactivated, the flies kept buzzing, found the study.

These memory consolidators inhibit wakefulness as they start converting short term to long term memory.

"Knowing that sleep and memory overlap in the fly brain can allow researchers to narrow their search in humans," said Bethany Christmann, graduate student in Griffith Lab, Brandeis University, Waltham, Massachusetts.

All these take place in a section of the Drosophila brain called the mushroom body, similar to the hippocampus, where our memories are stored.

As it turns out, the parts of the mushroom body responsible for memory and learning also help keep the Drosophila awake.

"It is almost as if that section of the mushroom body were saying 'hey, stay awake and learn this. Then, after a while, the DPM neurons start signalling to suppress that section, as if to say 'you are going to need sleep if you want to remember this later," Christmann pointed out.

Studies have shown that sleep is critical in converting short term into long term memory, a process known as memory consolidation.

Understanding how sleep and memory are connected in a simple system, like Drosophila, can help scientists unravel the secrets of the human brain.

"Eventually, it could help us figure out how sleep or memory is affected when things go wrong, as in the case of insomnia or memory disorders," Christmann concluded.

The study appeared in the journal eLife.