Whether you see meditation or prayer as the gateway to enlightenment or just a way to stay more focused at work, one thing that's certain is that the practice comes with a whole host of physical and mental health benefits.

But what's behind those benefits has been less clear. What's going on in the brain when we're sitting silently and focusing on the breath?

For the fifth episode of Next Level Living, a 10-part HuffPost Originals video series on the science behind our everyday habits, we asked scientists about what meditation and prayer do to the brain and body to create benefits like reduced stress levels, improved sleep, and, for some, mystical experiences.

"The more you do a practice like meditation or prayer, your brain physically gets thicker and it functionally works better," Dr. Andrew Newberg, a neurotheologist and director of research at Philadelphia's Myrna Byrd Center of Integrative Medicine, said in the video.

In his lab, Newberg took brain scans of spiritual leaders while they're meditated or prayed in order to learn more about how the practice alters brain activity. What did he find? Concentration and language centers activate, while the parietal lobe, which helps you gain a sense of where your body is in space deactivates. And surprisingly, the thalamus -- which is involved in our sensory perceptions of the outside world -- is also highly active.

To learn why meditation and prayer activate the thalamus, check out the video above. For previous episodes of Next Level Living, head over to our show page.

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