The whole podcast team is out in the field, so while we're away, we're bringing back a few amazing oldies from the archive.

Today, we dive into your brain during bouts of intense learning. Maybe that happens to you when you listen to this podcast.

Producer Karen Hopkins brings us a study that looked at brain training and how rest might be the key to training your brain even faster.

The episode first aired on July 21, 2021, when we were still called 60-second science memories. Enjoy!

This is Scientific Americans 60-second science. I'm Karen Hopkins.

They say that practice makes perfect.

But sometimes the best practice is not on a keyboard.

It's all in your head because a new study shows that the brain takes advantage of the rest periods during practice to review new skills, a mechanism that facilitates learning.

The work appears in the journal, cell reports.

A lot of the skills we learn in life are sequences of individual actions.

Leonardo Cohen of the National Institute of Neurological Disorders and Stroke, or NINDS.

For example, playing a piece of piano music requires pressing individual keys in the correct sequence with very precise timing.

That level of virtuosity requires a ton of practice and a lot of repetition. But Cohen says it also requires a certain amount of rest.

Also from previous research that interspersed in rest with practice during training is advantageous for learning a new skill.

In fact, we recently showed that virtually all early skill learning is evidenced during rest rather than during the actual practice.

It's during those intermittent breaks that the brain starts to sew together the individual movements that make up a seamless piece.

The question then becomes, how? To find out, Cohen and his colleagues turn to an imaging technique called Magneto Encephalography, or MEG.

The unique advantage of MEG is that it allows us to observe neural activity across the entire brain with millisecond time resolution, which is crucial for investigating very fast widespread brain dynamics.

Ethan Bush, Cohen's colleague at NINDS. They and their team had 30 volunteers sit inside an MEG scanner, and they asked them to type the sequence 41324 on a keyboard as quickly and accurately as possible.

The participants would type for 10 seconds, rest for 10 seconds, and then repeat. While the researchers monitored their neural activity.

And what we found was really quite interesting. So we actually found that the brain kept replaying much faster versions of the practice activity patterns over and over again during rest.

So a sequence that might take one second for fingers to type would take just 50 milliseconds for the brain to replay.

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