Flotation Therapy: The World of Sensory Deprivation Tanks



In a bustling neighborhood in southeast Portland, situated between an e-cigarette store and a barbershop, sits a strange little business called Float On. Each day, around fifty people walk through the shop’s front door and into a brightly colored lobby full of plants and couches. They check in with a desk attendant (that’s me), walk into a short hallway, enter private rooms, shed their clothes, shower, then climb into enclosed tanks full of luke-warm, epsom salt saturated water and float on their backs in total darkness and silence for at least 90 minutes.

The clinical term for this unusual practice is R.E.S.T., Restricted Environmental Stimulation Therapy, which is also known as “Floatation Therapy,” “Isolation Therapy,” and “Sensory Deprivation Therapy.” With six tanks, Float On is the largest float tank center in the United States. As with almost every other center in the world, Float On operates as a spa rather than a clinic, and none of our employees are licensed or trained as therapists. While some of our clients are referred to us by their therapists, most come of their own accord. We offer them some tea and water, minimal instructions on what to do before, during, and after the float, and then leave them to the experience. At the shop, we usually just call the practice “floating,” the tanks “float tanks,” and the clientele “floaters.” Over the three-and-a- half years our center has been open, we have run over 30,000 floats.

Our floaters are a diverse group: young and old, male and female, high income and low income. We float artists in search of inspiration and heightened creativity as well as business men looking for stress relief and better work performance. Some floaters use it as an easy form of meditation, some for the enhancement of athletic ability, some for relief from physical or emotional pain. For all of them, it provides a relaxing break from the stress and cacophony of the modern world and a quiet, peaceful space for the mind and body to unwind.

The first float tank was invented in 1953 by neurophysiologists Dr. John C. Lillly and Dr. Jay T. Shurley at the National Institute of Mental Health in Bethesda, Maryland. Early experiments with float tanks involved fully submerging participants in a cylindrical water tank, their heads encased in a breathing apparatus resembling a windowless space helmet, with air tubes running up to the surface to supply oxygen. The purpose of the experiments was to study the psychological and physiological effects of sensory deprivation. One popular theory at the time was that the brain, viewed from a behaviorist perspective as an organ that only responds to stimulation, would simply turn off and the subject would slip into a sort of mindless coma. Lilly and his colleagues quickly found this not to be the case.

The initial conditions were not ideal for total relaxation and many of the first test subjects found the experience extremely unpleasant. Nevertheless, once Lilly and some of his colleagues and subjects became more comfortable with the process and all the various apparatuses involved, participants found that they were able to drift into a state of heightened relaxation, often accompanied by spontaneous perceptions similar to dreams or hallucinations. Also a licensed psychoanalyst, Lilly soon saw the potential therapeutic applications of sensory deprivation. He developed what can be considered the first modern float tanks in the early 70s with the help of Glenn and Lee Perry, who went on to found the first commercial float tank manufacturing company. These tanks allowed the subjects to float on their backs on the surface of the water in a simple, easy-to- enter, light and sound proof box.

The term Restricted Environmental Stimulation Therapy or Technique (REST) was coined in the early 70s by Dr. Peter Suedfeld who, simultaneously with Lilly’s tank experiments, developed dry forms of sensory deprivation, which were also found to be therapeutically beneficial. Another pioneering researcher in the field was Dr. Rod Borrie, who worked with Dr. Suedfeld on several studies and went on to set up a psychotherapeutic practice and research center in New York City with float tanks in the 80s and 90s. Using a two way intercom, Borrie was able to guide his patients through their floats with sounds, suggestions, and music. He considered the float tank to be the “ultimate couch,” and a perfect environment for inducing hypnotic states. Together, Lilly, Suedfeld, Borrie, and other researchers in the field published dozens of studies that concluded REST could be beneficial in countless ways: improving memory, increasing hand-eye coordination, even reducing spasticity in sufferers of cerebral palsy.

Float tanks are quieter and darker than any normal room is likely to be, and the water temperature is held as close to 93.5 degrees fahrenheit as possible, which is the average surface temperature of human skin.

The water feels neither hot nor cold, and it becomes impossible to tell where the body ends and water begins, or even sense the difference between the water and the air on your skin.

The water is saturated with epsom salt to over twice the buoyancy of the famous Dead Sea in Israel, allowing the client to float without any effort, providing relief from the constant physical stress of gravity on the bones, muscles, and joints, while simultaneously delivering a large transdermal dose of magnesium, a natural muscle relaxant. All felt external bodily sensation is reduced to nearly nothing. Activity in the autonomic nervous system, responsible for the “fight-or-flight” response, slows down, resulting in lower heart rate, lower blood pressure, and slower breathing. Production of adrenaline and cortisol, the “stress hormone,” decreases, while serotonin, dopamine, and oxytocin levels increase. The electrical rhythms of the brain slow from alpha frequency waves (7.5 to 12.5hz), associated with normal waking consciousness, to theta frequency waves, associated with deep meditation or light sleep (4 to 7hz).

The benefits of floating are largely brought about by the body’s self-regulatory system. When external stimuli are neutralized, a normally functioning body reverts to a default state of relaxed well-being.

This state of intense relaxation buffers emotional reactions to internal and external events, allowing the subject to safely expose themselves to what would normally be anxiety-provoking thoughts, memories, and situations.

The overall intensity of the float experience varies from person to person. Ordinarily, floaters leave feeling a greater sense of well-being than when they came in. They are relaxed yet alert, smiling, and ready to face the world. Many report that their senses are heightened: colors look brighter, things taste and smell better. Clients often report feeling more at peace, centered, rejuvenated, present, optimistic, compassionate, and empathic. Brad, a friend and first-time floater, related the following experience to me, which serves as an excellent example of a typical float experience:

On the drive to the center, Brad was in a state of anger, stress, and agitation that was fairly typical for him whenever he got behind the wheel of an automobile. He felt nothing but contempt for the other drivers, bikers, and pedestrians, and bestowed upon them his usual barrage of epithets. He arrived at the center and the float itself seemed unremarkable, relaxing but a little boring. But after leaving the tank, he noticed that his mood was markedly different. He felt happier and more relaxed. On the drive home the rage was gone. The other drivers were now his friends and traveling companions, and he was happy to share the road with them. He arrived home to his fiancée and upon seeing her felt an upwelling of warmth and affection that was nearly overwhelming.

The peace of mind achieved in a float tank can be a valuable instructional experience to someone who has grown accustomed to living with stress and anxiety every day. It provides the floater with an opportunity to experience a state of mental tranquility they might have never experienced before, while showing them how far they really are from what should be their default state of relaxed contentment. It allows for the opportunity to achieve a greater self-awareness, to locate sources of physical and psychological pain, and observe the patterns and associations surrounding them. As the effects of a float wear off and the stress returns, little by little, the floater can perhaps have a greater chance of identifying these sources throughout his or her life (e.g. an unsatisfying job, an abusive spouse) and take action to avoid or reduce their effects.

Occasionally, a single float can be a dramatic and even life-altering experience for the floater.

These episodes may take a form similar or equivalent to the “peak experiences” described by psychologistAbraham Maslow, wherein the client undergoes an intense and euphoric feeling of loss of ego and “oneness with everything.” It may involve the healing of an old psychological wound by the revisiting and letting go of a past trauma, or it may involve a “Eureka!” realization about the nature of life and the universe. There may be an enormous emotional outpouring of tears or bouts of unstoppable laughter. These breakthrough float experiences seem to occur more prevalently in floaters who are under a great deal of stress and tension, but this isn’t always the case.

At Float On, we have created various programs allowing us to contact certain groups whom we believe could benefit from floating. We have had programs for artists, dancers, musicians, chefs, and writers. The vast majority of participants have reported that their float experience has enhanced their creative performance in some. Currently, we are in the process of developing programs to focus on specific physical and psychological afflictions, such as fibromyalgia, post-traumatic stress disorder, and insomnia. We hope that the data we collect from these programs will be useful for future scientific analysis relating to REST.

For one such program, which we call the “Floater X Project,” we select a volunteer suffering from a chronic physical or psychological difficulty and put them through six weeks of bi-weekly float-tank sessions. The participant is asked to record a journal entry after each float experience, fill out some questionnaires, and do a short pre-float and post-float video interview

For our pilot study, I asked my friend Hannah, who suffers from a severe anxiety disorder, to participate. Her symptoms at the time included muscle tension, headaches, and chronic nausea which led to vomiting multiple times a week, difficulty sleeping, stress, exhaustion, and depression. All of these symptoms decreased significantly during the course of the Twelve-Float program. At first, she had a much more difficult time growing accustomed to the tanks than was common with most floaters. She was unable to relax and had to leave the tank early during the first three floats. I was beginning to doubt whether she would be able to make it through the entire program. But her fourth float was the breakthrough:

4th Float: Sunday, February 23, 3pm

My float was different. I cried extremely hard for an hour, like no sound, just pain screaming from my soul. Then I laughed hard a bit, then back to crying hard again. Then I opened my eyes in total darkness, and I saw a lightning eagle shoot up from the darkest part of a sea with me on its back, shooting from the darkness. Then I cried more and I got out early because it was such an incredible time. But I realize I still have a lot of mental anguish deep inside me, and it’s going to be free like the lightning eagle shooting me free.

Another way we have collected float experiences is through floater-submitted testimonials we call “Tales from the Tank.” We give our clients a free float in exchange for sending us an essay about their float experience, which we then print as an advertisement in a local newspaper. As well as demonstrating the benefits of floating, the tales make for fascinating and often uplifting reading material. They show how our floaters use the tanks to aid in coping with grief and tragedy, and how floating can lead to unexpected, profound, and life-affirming experiences that last long after the floater has left our shop.

I had this sensation, like a spiritual sixth sense, that floating felt like death and that death was beautiful. The metaphor is apt. There’s your body’s struggle against weightlessness, which is like a person’s emotional and spiritual resistance to the concept of death. But, the struggle is the ugly part; the letting go and becoming nothing seemed beautiful to me. No suffering, no pain. And the idea that my existence would be no more didn’t seem horrifying to me, but made sense. I can’t tell you why it makes sense though. Death is the ultimate narcissistic blow. How can there be no me in the world? But, I had a vision of that narcissistic blow and it seemed fine and natural. I’m not a philosopher and, therefore, not up to such heavy matters. All I can say is during my float, I had the sensation that death is beautiful.

My father was diagnosed with brain cancer last month, so obviously I’ve been thinking about death a lot. Mostly, I’m scared for him because he lives with the daily knowledge that he probably won’t be alive this time next year. He is so scared and depressed. I can’t tell you why, but the float helped me. Of course, I’m still grief-stricken and don’t want to lose him. But I think he may just find that it’s beautiful at the end. 

Another fascinating and demonstrative account came to us from a floater named Emily who was participating in our Writers Program, where we give local writers free floats in exchange for a piece of poetry or prose after each float, which we then archive with the intention of publishing in a future book. It was her third float of the program, and by her account, the most amazing float that she had experienced thus far. Breakthrough floats often seem to occur during the third or fourth session.

She had received advice from a friend and seasoned floater who suggested she try a “Choose Your Own Adventure” float. She was to pick a place she would like to visit, real or fictional, and then try to travel there in her mind while in the float tank. Upon attempting to follow this advice, she suddenly found herself in her childhood home, revisiting a traumatic past experience involving her abusive alcoholic father: 

I asked myself where I would like to fly to, anywhere and anytime, and I unhesitantly chose to go back the kitchen of the house I grew up in. It was a typical evening, I was about 10, and my dad was a drunken terror, making mutters and snide comments under his breath. 

Why did I fly here, right?! Hawaii or New York City would be way more fun, but, for some reason, I wanted so badly to go here. I guess I felt like investigating, rather than laying out on a beach.

Emily later told me that while she was reliving this childhood memory in full detail, she was also fully aware that she was in the float tank. She maintained the psychological perspective of her adult self, but was viewing the scene through the eyes of a child. She said the experience was very healing, and that she found herself able to let go of some of the pain and anger she had carried since childhood.

As part of my role at Float On, it is my job to facilitate these programs, interacting with the participants and collecting, archiving, and categorizing their stories. And when I work in the shop I am often the last person to talk to a floater before his or her float, and the first person to talk to them afterward. The stories I hear and read day-to-day are often amazing and inspiring, and the change in a person before and after a float is obvious. When they get out, they have what we call the “post-float glow.” Sometimes a floater will walk up to thank me with tears in their eyes. It’s one of the most rewarding jobs imaginable. 

Float business is booming, with appointments at our center booked to capacity nearly every day, and new float centers springing up all over the country. While we’re extremely optimistic about the future of floating, we’re also aware that there is enormous room for growth and improvement. Nearly every float tank in the world right now is run at a private residence or in commercial “spas” like Float On. Only a few are currently being used for clinical therapy or medical research. We want that to change. Floatation therapy is far too effective not to be available to those who will ultimately benefit from it most.

About Stanley Siegel

Stanley Siegel, LCSW, is a psychotherapist, author, lecturer, and former Director of Education and Senior Faculty member of New York's Ackerman Institute for Family Therapy. After creating and writing the "Families" column for Newsday he went on to co-author two popular books: The Patient Who Cured His Therapist and Other Unconventional Stories Of Therapy(Penguin/Dutton 1992; Penguin/Plume, 1993; Marlowe and company, 1999) and Uncharted Lives: Understanding The Life Passages Of Gay Men (Penguin/Dutton, 1994; Penguin/Plume 1995) which have been translated into 5 languages. With nearly 45 years of experience in the field of psychology, Siegel has developed an unconventional and tradition-challenging approach to psychotherapy[4][5][6] that has led to his book Your Brain on Sex: How Smarter Sex Can Change Your Life[7] which was released in October 2011. He was a sex columnist for Psychology Today and the author of How Sex Heals and The Secret Wisdom of Ancient Parables. Siegel founded Psychology Tomorrow Magazine and Wellness Providers Network. Siegel has taught at the State University of New York at Stony Brook, Adelphi University, and the University of California, Berkeley; was the founding Director of the Family Studies Center in Huntington, New York, and has served as a consultant to hospitals and mental health centers throughout the country. Regularly quoted in the media, he has appeared on ABC's Good Morning America several times,[8] as well as many other television and radio programs, and has acted as a consultant for film and television. Siegel was invited on The Oprah Winfrey Show to discuss "How Healers Heal Themselves." He served as the Dance Editor of Show Business magazine, writing weekly dance reviews and reporting on the contemporary dance scene. His daughter, Alyssa Siegel, LPC lives in Portland, Oregon and is a contributor to Your Brain on Sex. After a lifetime in NYC, he moved to Los Angeles in 2016