What Is ‘The Sensory Deprivation Tank Experience’?

An isolation tank, ‘float’ tank or sensory deprivation tank (or chamber) is one of the few environments on earth where a human being can experience almost complete sensory deprivation (hence the name.) It’s known holistically as the ‘sensory deprivation tank experience’ because, as you’ll see, it really is an experience — there’s no way to truly put it into words. (Despite this, I will of course do my best to do so here.)

Basically, you float in a foot of water that’s had over 800 pounds of salt dissolved into it, and is heated to exactly your body temperature, in a room where no light or sound penetrates.

After a few minutes, the sensation of the water on your skin fades, and you’re left completely alone with your thoughts. In the tank, there’s nothing to distract you from these thoughts, and so they become incredibly vivid. Basically unable to sense your body at all, you become the pure, naked sensation of the moment-to-moment mind. This can lead to tremendous insights, powerful visions, and deep meditative states.

Isolation tanks were invented by John C. Lilly in 1954, for the purpose of understanding the effects of psychedelic drugs on the human mind. Only in later decades were the tanks discovered to be an excellent environment for healing the body and the mind — what is now known as floatation therapy.

5 Things I Learned From ‘Floatation Therapy’

1) The Modern Brain Is Addicted To Stimulation

After undressing, showering, and laying down in the deprivation chamber for the first time, I was finally greeted by. . . absolutely nothing. Perfect darkness and silence settled down on my brain, and it felt awkward at first. I kept telling myself to relax, but I just couldn’t.

I had only dabbled in meditation, and foolishly assumed I would be able to achieve a thoughtless state in the isolation tank. Instead, my mind found ways to entertain itself. Strange thoughts arose, and my mind observed them in the same way it observes television, or any other entertainment.

In an environment void of stimulus, my mind was creating its own. Fragments of songs and movies kept entering my mind’s eye and ear — without my consciously willing them to do so, it should be added. It was an incredibly surreal — and frustrating — experience. My mind was so used to cycles of stimulus and reaction, that it felt starved in this stimulus free environment. Then, just as a starving man would, it began using its own energy to continue functioning in the way it was accustomed.

The chaotic thoughts continued for about half an hour, until I finally got it under control through focus on the breath. But by then, the tank had woken me up to a startling reality. My mind craved stimulus and outside entertainment in an unhealthy way. I was an addict. And my drug of choice had been my cellphone and computer screens, constantly feeding me novel and exciting information.

I realized then it was time for me to disrupt that addiction. I resolved to take my meditation practice seriously, and limit my time with electronics in a major way.

“We have been to the moon, we have charted the depths of the ocean and the heart of the atom, but we have a fear of looking inward to ourselves because we sense that is where all the contradictions flow together.”

~ Terence McKenna

2) Time Doesn’t Exist If You Can’t Measure It

In my second session of ‘floatation therapy’, the sensory deprivation tank experience was to be 90 minutes long. I was excited to see what states of mind I could achieve with so much time. But I would estimate that within twenty minutes of entering the float tank, I was wondering if I was almost done. By about forty minutes I assumed the staff members had forgotten about me.

This sounds strange at first, but it actually makes perfect sense. In an environment devoid of stimulus, there’s nothing to measure the passage of time by. I can’t refer to past events, or a clock, or the movement of the sun, or the temperature. There’s nothing in the float tank to prove that any time has passed at all — or that it even exists. Nothing decays, or gets cold, or changes in brightness. The only changing thing in the tank is you.

About an hour into the session — or ‘the float’, as I and others have come to call it — in a desperate attempt to measure the passage of time, I found myself referring to past thoughts as events. I thought, “The first thing I thought about in the tank was my car, which led me to think about the economy, and I thought about that for a while, which led me to thinking about my job, so I must have been in here about ten minutes.” This seems ridiculous, but when your mind has nothing else to grasp onto, it takes what it can get.

Here’s where it gets even weirder — after my time in the isolation tank, it felt like barely any time had passed at all. I exited the tank room feeling like I had just taken a nap. The clock showed that time had passed, but I had no other evidence to back that up. I entered the tank, and then exited it, and somehow… I was 90 minutes in the future. That experience taught me to appreciate the sun, and how it lets us intuitively track the passage of time.  

3) After All The Noisy Thoughts Fall Away, You’re Left With Bliss

After stepping out of the tank for the first time, I experienced something I hadn’t known since early childhood: thoughtlessness. No dialogue filled my head as I showered and put my clothes back on.

As my friend and I left the tank facility, we both agreed that this was the most relaxed we had ever been. This was one of the obvious, immediate benefits of floatation therapy we had been looking for. In the isolation tanks, our minds had burned through all the noise and chaos they usually produce. After exhausting all their juice in the tanks, our minds had nothing left to do but experience the present moment.

The feeling was akin to a combination of runner’s high and the complete refreshment that follows a good sleep. The effect was most noticeable right after exiting the tank, but it lasted for days afterwards. Much like meditation, an experience in a tank can be said to benefit you forever.

My second session of floatation therapy was even better. Leading up to the float, I practiced meditation daily for several weeks. After a few minutes in the tank, I thanked myself for the effort. My mind didn’t recoil and panic at the absence of stimulation. Instead, it focused. I let my thoughts drift for a while, and then eventually settle down into a state of near total relaxation.

This state only deepened as time went on. As I exited the tank room, my friend and the staff member laughed at the blissful grin that ran across my face. I hadn’t even noticed I was smiling. It just came as a natural result of the state the floatation therapy had put me in. And it’s important to note that this wasn’t a state of ecstasy or excitement. It was a state of thoughtlessness.

4) Your Body Carries A Huge Amount Of Tension

As I relaxed into the float, I started to feel my muscles unburden themselves and lengthen in a way I never had before. In basically any position, your body is stressed in some way. Not so in the tank. Not only does a single muscle not need to be tightened during floatation therapy, it’s nearly impossible to keep them from turning to butter in there.

One by one, you feel your bones, sinews, tendons, muscles and joints settle into a comfortable place (and yes, you really do become that aware of your body inside the isolation tank — at least, I did). Soon after, your entire body goes totally ‘numb’ and you’re left with only your mind. But you’re in for a whole new sensation once you exit the tank.

The first moments of standing straight after emerging from the tank are hard to describe. The spine feels long, flexible, and relaxed. The shoulders hang loose, finally free from the tension most people hold in them. The neck extends up naturally from the spine, as if your skull were held up by a string.

Of course this results in good posture, but it’s not your grandmother’s good posture. It’s posture that’s the result of relaxation, not discipline. Once you feel this, you realize how long you’ve been doing things wrong! It’s like you’ve regained something you’ve been missing your whole life, and you couldn’t imagine standing any other way, as it would just feel so ‘off’.

A friend of mine who went for floatation therapy explained to me how after exiting the tank, back pain that had plagued him for years was suddenly gone. If the Isolation tank’s effect on the mind is similar to deep mediation, then the effect on the body is similar to a full body massage. Muscles I didn’t even know I had suddenly felt flexible, at ease, back in full form. My joints felt loose and smooth. I felt like every squeaky and rusty hinge in my body had finally been oiled.

5) Everyone That Tries The Tank Loves it

After my float, I spoke to the owner of the center. I was curious to know the make up of his clientele, and what their reasons for pursuing the sensory deprivation tank experience were. What he told me came as a big surprise.

He said that his clients raged in age from 10 to 80, and that their reasons were as diverse as their ages. Some, like me, came to explore altered states of consciousness, and deepen their meditation practices. Others came to alleviate back and joint problems. Many were athletes recovering from injuries.

Even more impressive was what the owner told me about the general reaction to the tanks: everyone loves them. Young and old, spiritual and skeptic, nearly everyone that uses an isolation tank gets something valuable from it. I guess that must be good for business.

Conclusion

So again, in the end, the ‘sensory deprivation tank experience’ is just that — an experience.

Inside the float chamber, mind and body are brought together in a manner it’s impossible to describe (or avoid), because most of us spend so much of our lives experiencing them as (and believing them to be) separate. Once you’re in there, without a body, you realize the ongoing relationship between the two as the evolving bio-mechanical feedback system they really are, ever in relationship to itself and the environment, and the utter importance of your thoughts (and lack thereof), as well as the mindfulness of your body and emotions.

Floatation therapy is a true hidden gem in the world of personal development and spirituality. I’d recommend the tanks to anyone open-minded enough to learn about them.