When you open the door to the float room, you’re hit with warm air heated to the temperature of your skin. In the middle is a small, circular pool the size of a hot tub filled with 2,000 pounds of Epsom salt. Sit down, and you’ll bob like a buoy; lie back, and you’ll float without tensing a muscle. Press a button on the side of the tank, and the blue lights fade off into black.
You can’t see anything while you float. But what Feinstein can see going on in your brain is astounding.
In his research, he has floaters stick small waterproof sensors and an EEG device on their forehead to measure their brain waves, wirelessly. Down the hall is an MRI machine that people enter after they float.
Feinstein and his team are more than halfway through the first experiment ever to combine fMRI brain imaging and float tanks. They’re scanning the brains of healthy people before and after they float, and by comparing the two images, they’ll see how floating changes areas of activation in the brain.
Recent advances in neuroscience have allowed scientists to look inside the human brain during practices like meditation and see how brain activity changes. Research from fMRI studies show that meditating activates parts of the brain associated with attention and decreases activation in the amygdala, the part of the brain that kicks off the fight-or-flight response to a real or perceived threat—though the changes are more pronounced in expert meditators than beginners. Plenty of other research demonstrates the benefits of the practice, and its acceptance by the medical establishment has followed. The stance of the National Institutes of Health (NIH) is that research supports meditation for lowering blood pressure, easing symptoms of anxiety and depression and more, and the agency funds research on the topic.