Transcript for Sensory Deprivation: An Altered State of Mind

mind altering, possibly even life changing experience and all you need is water and salt? Fans of the hot new trend are spending time in isolation tanks where they say a dip can help ease your physical problems and maybe even mental ones. Here's ABC's reporter. Reporter: Life seemed more hectic and stressful, and your brain is constantly spinning -- "Nightline" is about to take you on a journey to a strange alternate world on the other side of this hatch. This is a unique opportunity for -- for stillness and rest and privacy. Sean Mccormack is in the sensory deprivation business. One foot in. Other foot in. Pull this over you as you crouch down. Here at float Seattle customers are offered a chance to get away from it all by floating in a closed box. Filled with 10 inches of water, loaded with 1,000 pound of epsom salt. There is no light. No sound. No distractions. All you do is float. It can be harder than it looks. And for some people, they end ear deep meditation. Even hallucinate. Sensory deprivation, telling nothing. The outlet to unplug. Even turning your phone off for an hour is a big deal for people. Here it is not only your phone but you are shutting out the world. Scum with me. I will show you. Sean is no long-time guru or life coach, a former raidy ad salesman. But he has been medicating since he was 12 and became obsessed with floating in a friend's make shift tank. My experience was fantastic. And kempt thinking about it. Reporter: The impact was so deep he recently changed careers and opened his own business. You are all set to go. Have a good float. Thank you. Thank you. You step in. Your head is going to go at this side. It's really warm. I felt like the only way to truly understand was to try it. This is a really unique opportunity to be away from things. I am never away. This is it. Your bed and your brain have been waiting for this, opportunity, for true stillness. I had heard that some people freak out, we rigged my tank with a night vision camera. As I closed the door and set noold wa ted into the warm water. I had no idea that my day was about to change. The idea of sensory deprivation tanks and floating isn't new. John lily first developed them in the 1950s to discover the effects of total isolation on the brain. In his case, some times while using drugs. A practice made famous and terrifying by the 1980 science fiction move vie, William hurt is a scientist whoing prores to a murder murderous. And it has showed up from fringe to the simpsons where even Lisa and homer took a trip. How am I supposed to hallucinate with these swirling colors distracting me. Meanwhile inside my strange little world. I see a few flashes of light. Not unlook what you might see when you close your eyes. I am relaxed bought ware that I am doing a story on all of this. My brain wasn't going anywhere strange so far. It turns out scientists first thought the brain would shut down without incessant input. What researchers found is just the opposite. It enters a state similar to meditation. But by eliminating graph tef through floating it goes deeper. There has been quite a few really good studies showing, overall reduction in pain. Overall improved mood, understanding, awareness of their body. This doctor is a physical therapist whur studied flotation and offers tight help some of his patients. I was blown away, they came out. Physically. Mentally, cognitively relaxed. We see people come out of the tank. Their muscles are functioning better from an anecdotal standpoint. For some it can be life changing. A cardiac care nurse, stopped smoking and drinking after she beef can floating and seeing thingsen a whole new light. That immediate impact. You walked out the door from a float. And you said no. I couldn't dupe it. I was, very taken aback. I hallucinated before. I had out-of-body experiences. It's been insightful. Learned more about myself. I feel like I have my whole life. Reporter: The profound reaction is the reason that Sean stays all people coming through his door. Who wants to float? A lot of people who were working day in day out really hard and need a break. Planning the rest of your life. The day, what you are going to do, get done. What you mav to do that quiets down. You can't seep it in my face. Some way around the halfway point of my hour inside. I goechl some where. And it isn't at all like a dream. When the music comes on. Signaling the end of my float. I don't want to leave. It was my childhood. I was touring every room of my childhood home in detail. Crazy detail. I couldn't shake it. I wasn't asleep. Yet visions were crystal clear like the flashback you see in the movies. Definitely completely left my Normal life. I wasn't thinking abut work. I was thinking about, everyday stuff. It just popped in there. I don't know how much, it just popped in there. The kitchen table, right, the bedroom. Other, you know -- brother's and sister's room. The family dog. Reporter: Certainly not everyone reacts the same. But for me it may not be altered states. But a trip, far, far away from the hustle and bustle of reality. And deep inside your own mind. Nechlt il karlinski for "Nightline" in Seattle.

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