Numerous studies have linked a good night’s sleep to better memory, but there hasn’t been a clear answer of how it worked … until now.
Scientists at New York University and Peking University Shenzhen Graduate School used advanced microscopy to witness new connections between brain cells forming while study mice slept.
For the study, researchers trained mice in a new skill – walking on top of a rotating rod. They then looked inside the living brain with a microscope to see what happened when the animals were either sleeping or sleep deprived. Their study showed that sleeping mice formed significantly more new connections between neurons, and thus were learning more.
The scientists also learned, by disrupting specific phases of sleep, that deep or slow-wave sleep was necessary for memory formation, because during this stage, the brain was “replaying” the activity from earlier in the day.
In the end, the mice with more sleep formed more brain synapses, and performed better on tests of their new skill than mice that had not slept enough.
Lead researchers say it reinforces the idea that for kids preparing for a test, studying and then sleeping is better than staying up late to study more.