sensory deprivation chamber
Photo: Ciara Phelan
I don't suffer from claustrophobia; I've never had that nightmare about being buried alive. But when I get to Manhattan's Aspire Center for Health + Wellness and see the Restricted Environmental Stimulation Therapy (REST) tank—bright blue and egg shaped, like something out of Avatar—I feel a twinge of doubt. "I'm going to be in that for an hour?"

The REST tank is an eight-foot-long pod filled with ten inches of water, kept close to skin temperature at 95.7 degrees, and 1,200 pounds of Epsom salt for buoyancy. Inside, it's pitch-black and dead silent.

This is the 21st-century version of the sensory deprivation tank, invented by neuroscientist John C. Lilly in the 1950s to explore how greatly reducing the sensations of sight, sound, and gravity affects consciousness. Over the years people found the tanks calming. Indeed, proponents of REST claim that floating leads the brain to generate more theta waves (which are prevalent in light stages of sleep) and induce a state of relaxation we usually achieve only in deep meditation. Today floating is on the rise as an alternative to meditation. My brain is always in overdrive, so I'm eager for a radical downshift.

I shower, pop in earplugs, and, still naked, step into the tank. The water feels surprisingly chilly as I slosh to the front of the open pod, my feet dragging against the salt's weight. I sit down, then lie back—and just like that, I could be floating in the Dead Sea. I push one interior button to lower the top and another to turn off the light. "Here we go. Just breathe. Yeah, right." Trying to zone out in the darkness, without my iPhone to distract me, is tougher than I'd imagined; all my thoughts just have more room to ramble: "I forgot to text Mom. What's for dinner? Is there a hidden camera in here?" I try to deeply inhale and exhale for ten minutes or so (I think; I've lost all sense of time) and then realize I can no longer even feel the water—whoa! This is a real trip. Next thing I know, my right arm is jerking, splashing, and jolting me back to consciousness. "Did I reach theta?" Before I have time to contemplate this (or fret that the staff has forgotten about me), the faint sound of crashing waves fills the pod, signaling the end of my session. I can't believe an hour has passed.

After I rinse away the flecks of salt in the shower, I find I'm clearheaded but also relaxed—in fact, sedated. Back at the office, I can't help reclining in my chair; my coworkers have to ask me to speak louder. That night, I fall into a magically deep sleep (the magnesium from the salt, I've read, has a relaxing effect on the body).

My chillax buzz (and amazing sleep) lasts nearly a week. Tight deadlines at work don't feel paralyzing; I don't huff over subway delays on my commute. Avid floaters treat tank time like regular massages, unwinding in the pod every month or so. I'm not ready to take it that far, but next time I'm in sensory overload, I'm going to draw a warm bath, grab my eye mask and earplugs, and try floating my cares away.

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