Meehan Crist - Postcards From the Edge of Consciousness

A week or two ago, I posted an article on one guy's first experience of a sensory deprivation flotation tank. Strangely, here is another one, this time from Nautilus, after several years of never seeing anything written on this topic.

Are sensory deprivation tanks making a comeback?

Postcards From the Edge of Consciousness

Sensory deprivation goes from CIA torture manuals to a yoga studio near you.

By Meehan Crist | Illustration By Vivienne Flesher 
August 14, 2014

I AM FRESH from the shower, wrapped in just a towel and smelling of mild herbal soaps (both shower and soaps are required), standing at the door to the tank. It resembles a shower door—knee-high, sliding—and opens to reveal a tub bigger than a bathtub but smaller than a hot tub, with a bulge in the middle. The tub is molded from a pale blue material that reminds me of above-ground Jacuzzis from the ’70s. The walls are padded with soundproof material. Overhead, the ceiling looks low enough to touch. There are no windows. Sam Zeiger had this tank built into his Chelsea apartment nearly 30 years ago and he is currently down the hall, in the living room, which has been modestly closed off from this half of the apartment by a folding screen. I am not uncomfortable, though I am, perhaps, in a state of nervous anticipation. This is my first float.

Leaving my towel outside, I step in and slide the door shut behind me. The air is humid and close. The smell reminds me of the inside of an old sailboat—salt and weathered fiberglass. The water is loaded with more salt than the Dead Sea, and both air and water are kept at skin temperature, so that as you float it is hard to say where body ends and environment begins. Once the lights are off, the darkness is total. The tank offers a reduced sensory experience as close to nothingness as you can get.

Slowly, so as not to disturb the water into motion, I lower myself down. The water feels thick. Slippery with salt. I lie back and feel for the big round button I’ve been told will be on my left. When I press it the lights go dark, and I begin floating.

YOU'LL HEAR things that you don’t normally hear,” Zeiger had said as he prepped me in his living room. “Your heart beat, your blood flow. A lot of people report hearing a quiet, high-pitched whine, which is your nervous system.” The proprietor of Blue Light Floatation, Zeiger is neither scientist nor clinician, but for the past 29 years, he has hosted a steady stream of floaters and attained something like cult status. The flotation community leans a bit New Age, and Zeiger’s living room, which smells pleasantly herbal, features floor-to-ceiling bookshelves lined with titles such as Indestructible Truth, You Are the Eyes of the World, and The Attention Revolution. Tibetan prayer flags are draped over a lamp at one end of the brown leather couch. I have come because flotation has seen a popular resurgence in recent years, with commercial tank operators popping up across the country, and I’ve heard stories both fantastic and mundane about the reduced stimulus experience. It can cure terrible, lifelong phobias. It helps with chronic pain. It is a portal to other dimensions. It is relaxing. 

 

Into the Tank: Today, most commercial flotation tanks are stand-alone boxes with a hatch that opens at one end. But some, like the tank in Sam Zeiger’s apartment in Chelsea, are specially-designed rooms that are more like a large shower stall.David Seefelt/High-TechFloatation

Research suggests that something rather remarkable happens when sensory stimulus from the external world is reduced to nearly nothing. REST, or Restricted Environmental Stimulation Therapy, as floating and the related dry chamber methods are known to researchers, has been shown to slow the heartbeat, reduce blood pressure, and release muscle tension. It increases levels of endorphins and lowers levels of adrenaline, as well as stress hormones such as cortisol. Some of these effects can be measured across sessions. Cortisol levels, for example, tend to go down after the first session, then go down further and stay down after repeated sessions. Clinically, REST has been shown to help with tension headaches, hypertension, and chronic pain, as well as performance enhancement. Basketball players, tennis players, dart players, skiers, and pilots all perform better after REST. Scores on memory and cognition tests improve. Some subjects report powerful emotional experiences, as in a particularly intense session of psychotherapy, and nearly all subjects report greater relaxation and an elevated mood after floating.

But why? Sensory Deprivation: Fifteen Years of Research, published in 1969 and edited by John P. Zubek, was the first authoritative overview of what was then called the “sensory deprivation” literature. The book catalogues an array of promising findings, but as REST researcher and pioneer Peter Suedfeld noted in a 1994 issue of the Journal of Environmental Psychology, “researchers had generated many facts, but had failed to propose and test a theory that would explain the wide-ranging and impressive changes in functioning that were evidenced during or after REST.” Nearly a decade later, we have more facts and a growing store of anecdotal evidence, but a scientific explanation is far from complete. Beyond the tantalizing promise of clinical applications, a better understanding of how flotation affects the mind and body may offer insight into a common but poorly-understood twilight phase of consciousness that occurs between waking and sleeping, when the lines between conscious and unconscious begin to blur and the mind begins to unwind.

AT FIRST I cling to the tank, fingers splayed and pressing up against the sides. Then I let go. My mind offers this: unmoored. The saltwater makes me so buoyant that I float without any effort at all. The darkness behind my eyelids is indistinguishable from the darkness of the tank. But I am naggingly aware of a line along my skin where water meets air. I think about this line, and whether I should be thinking about it. Some say that the experience of flotation is similar to meditation, and this is certainly reminiscent of meditation—the mind twitching and fretting like a puppy tied to a lamppost.

But the sensory experience of floating is like nothing else. The only sounds come from inside the body: the whooshing rush of each breath filling then escaping the lungs, the echoing thump of the heart in the chest. At some point (has it been five minutes? 10 minutes?), I realize I can’t tell if my eyes are open or closed. When I twitch my eyelids to check, the sound of the ensuing blink is a resonant boom. A rumbling begins somewhere behind my right ear, as if a truck is coming around the curve of my head, and as it thunders past, I realize an air bubble has been loosed from my hair. There are subtler noises as well, a regular swish like the hem of a woman’s dress brushing a marble floor—my blood circulating.

Suddenly, my left foot touches the side of the tank and my whole body tenses. I use my toes to push off, followed quickly by my right foot bumping up against the other side. I have pushed too hard. Though I can’t see anything, I am acutely aware of the boundary the tub inscribes around me. After a few more bumps and gentle pushes, my body and the water make peace, and I stop fixating on the tank. Then I discover I can’t think about the tank. I can’t mentally place where the sides might be or where my body might be in relation to anything else. My brain keeps asking my body, where am I? And my body keeps saying, um, I don’t know…

This is when I begin to get dizzy. I swear my body is spinning clockwise on the surface of the water, so I prepare to bump the left side of the tank, but I don’t. This is wildly disorienting. It’s as if the tank has disappeared and I’m spinning in endless space.

BECAUSE flotation simulates the weightless conditions of space, NASA has used flotation tanks to train its astronauts.

BUT BEFORE astronauts and the New-Age embrace, there were Cold War fears about brainwashing. The reduced sensory environment of REST grew out of experiments secretly funded by the CIA in the 1950s and 60s, on what was then termed “sensory deprivation.” In the early 1950s, remarkable video footage surfaced which showed American GIs taken captive in Korea denouncing capitalism and imperialism, prompting the CIA to ask: how could these extraordinary confessions have been extracted? The intelligence community suspected a powerful new mind-control technique. In a sensational and hugely popular book published in 1951, Brain-Washing in Red China, the journalist and secret CIA propagandist Edward Hunter proposed the term “brain-wash,” a literal translation of the Chinese his nao, to “wash brain.” If Communist powers had figured out powerful new mind-control techniques, then Western powers needed to catch up. It was a psychological arms race that could only be run by scientists studying the human mind.

The CIA’s interest in sensory deprivation as a potential mechanism of brainwashing was sparked by the illustrious psychologist Donald Hebb of McGill University. Hebb is best known for the famous dictum “cells that fire together wire together,” referring to a theory about neural mechanisms now foundational to modern neuroscience. Less well known is the fact that he attended a secret meeting at the Montreal Ritz-Carlton on June 1, 1951, along with high-ranking representatives from the defense departments of three countries—Britain, the United States, and Canada. At this meeting, the question of brainwashing was raised. Hebb, then chair of the Human Relations and Research Committee of the Canadian Defense Research Board, speculated that prisoners might be more malleable if placed into isolation with limited sensory input. The others were impressed. Three months later, he began research funded by Canada’s Department of National Defense (and carefully monitored by the CIA) into the effects of sensory deprivation. As Alfred McCoy reports in A Question of Torture: CIA Interrogation, From the Cold War to the War on Terror, within the intelligence community, one stated goal of the research was to prepare soldiers taken hostage and subjected to mind-control techniques. Hebb published the results in a 1954 issue of the Canadian Journal of Psychology under the guise of a study on monotonous environments such as those experienced by long-distance truck drivers.

The experimental setup Hebb designed looks very little like today’s flotation tanks. Twenty-two male student volunteers were paid $20 a day, twice the average daily wage, to lay on a bed in a chamber designed to induce “perceptual isolation.” The students wore a translucent plastic visor that emitted diffuse light to prevent “pattern vision,” as well as cotton gloves and cardboard cuffs that went from elbow to fingertips to reduce tactile stimulation (see The Early Days). A U-shaped foam rubber pillow helped dampen auditory stimuli, but an air conditioner in the ceiling remained on 24 hours a day, emitting a steady hum of white noise. The students were allowed breaks to use the bathroom and eat meals, which many ate sitting at the foot of the bed. They were invited to stay as long as they liked, but most could not make it past two or three days. 

 

The Early Days: In the 1950s and ’60s, early sensory deprivation researchers experimented with a wide array of techniques for reducing sensory stimulus. Here, one of Hebb’s volunteer subjects lies on a bed in a specially designed chamber, wearing a visor to reduce visual stimulation, padding around the ears to reduce auditory stimulation, and cuffs from the elbow past the fingertips to reduce tactile stimulation. Most subjects could not stand to remain in such conditions for more than two days.Credit Unknown

The results were startling. Subjects’ cognitive skills deteriorated rapidly and most experienced powerful hallucinations. As one of Hebb’s graduate students, Woodburn Heron, wrote in a 1956 issue of Scientific American, “Our subjects’ hallucinations usually began with simple forms… Then the visions became more complex, with abstract patterns repeated like a design on wallpaper, or recognizable figures, such as rows of little yellow men with black caps on and their mouths open. Finally, there were integrated scenes: e.g. a procession of squirrels with sacks over their shoulders marching “purposefully” across the visual field, prehistoric animals walking about in a jungle, processions of eyeglasses marching down a street.” Some subjects experienced auditory or tactile hallucinations, as well—“one had a feeling of being hit in the arm by pellets fired from a miniature rocket ship he saw.” Many participants refused to finish the experiment.

The CIA, however, was most interested in the students’ receptivity to beliefs that had previously been rejected. Before going into the chamber, participants were given various tests and questionnaires, including one gauging belief in paranormal phenomena. While the participants were in the chamber, Hebb’s team played “a recording of a talk arguing for the reality of ghosts, poltergeists, and other supernatural phenomena.” Apparently, even those who had reported not believing in such phenomena found this talk quite convincing. “Some of them reported that for several days after the experiment they were afraid they were going to see ghosts.”

Realizing the implications of his work, Hebb soon abandoned the study of sensory deprivation, but flame had been put to fire. Seven years after the McGill study was published, 230 articles on the subject had appeared in scientific journals, and behind closed doors controlling sensory environments had emerged as a way to soften prisoners before interrogation. In a confidential report to the Canadian Defense Research Board, Hebb noted that four of the students in his study “remarked spontaneously that being in the apparatus was a form of torture.” In the last interview he gave before his death, he said, “It was clear when we gave our report to the Defense Board that we were describing formidable interrogation techniques.”

This formidable potential was not lost on the CIA. During the 1950s and ’60s, multiple CIA projects funded scientific research on psychological torture and interrogation techniques, including sensory deprivation. The most expansive was the now-notorious MKUltra project, which used (sometimes unwitting) American and Canadian citizens as test subjects in a wide-ranging research program on mind control. As McCoy notes, the CIA dispensed $25 million for psychological experiments on human subjects to researchers at non-governmental organizations, including 44 universities and 12 hospitals. The chilling outcome of this research was made public only after The New York Times published an exposé on U.S. involvement in torture and assassinations in Honduras, and the CIA was forced to release the interrogation training manual known as KUBARK. Dated 1963, the last year of the MKUltra program, KUBARK details interrogation methods that include periods of both sensory overstimulation and sensory deprivation.

Researchers now recognize that many of the dramatic effects of Hebb’s research were not the result of reduced stimulus, per se, but to monotonously-repeated overstimulation: the lighted visor, the white noise, even the pressure of the bed against the back. But the study became recognized as a landmark investigation into sensory deprivation. And sensory deprivation continues to be associated with torture, obscuring the fact that dramatic negative effects such as hallucinations, intense anxiety, and mental breakdown are not merely a result of restricted sensation, but of how sensation is manipulated and under what circumstances.

I AM reluctant to admit it, but some corner of my mind was vigilant for the onset of hallucinations. For regression and psychological breakdown. For the dissolution of the self into nothing.

I try to relax. Breathe slower and deeper. I try to release the tension in my legs and arms, to let my head drop into the water as it might drop onto a pillow. This is harder than you might think. My neck stretches a tiny bit longer. My head drops a fraction of an inch. And then I am stuck. Focusing on my shoulders, I think, relax. The tension maintains a vice grip. Goddamnit, I think, relax.

What I did not expect: once I stopped trying so hard to relax, my attention turned inward, burrowing through bodily sensation like geological layers of sediment. I become aware of the curve and stretch of each muscle, the pull of tendon and ligament. I notice the meat of my upper arms as distinct strips of flesh around a solid core of humerus. I feel my ribs as what they are, a bone case for my organs. Cosmonaut of my own anatomy, I go deeper and become aware of stomach and gut, the spaces carved out for food and waste and fetus, all of it pulsing as the bone case yawns open, then draws shut, with every breath. How have I never noticed all this, before?

WAIT, did I fall asleep? I am suddenly aware of myself as a pinprick consciousness in a vast dark, where before I was not, which makes me wonder if I have just woken up. How long have I been in the tank?

My right shoulder twitches. My right forearm. My left calf muscle. It’s like those involuntary muscle twitches you get right before you fall asleep. Except that I’m not falling asleep, I’m waking up. Or letting go. This body doesn’t seem to belong to me. Muscles are releasing like the first raindrops of a quickening spring shower. It is both exhilarating and utterly relaxing. I’m not trying to do anything, anymore. I’m watching.

Here, beyond conscious control, is the previously unattainable physical release. My shoulders go. My neck relaxes. The muscles along my spine elongate and a subtle ache lodged in my back for months finally disappears. I can’t remember the last time I felt this good.

But how can I describe this other feeling, being utterly present while also being outside my body and outside time? Of being connected to everything and nothing?

The only way I can describe it is that floating feels like being meditated. As if the tank does it for you, from the outside in.

THE AVERAGE brain is an electrochemical organ that generates as much as 10 watts of electricity, enough to power a small light bulb. This electrical activity can be recorded in the form of brainwaves that have higher or lower frequencies and amplitudes, and the four most common—beta, alpha, theta, and delta—roughly indicate levels of arousal. Beta waves are short and fast and associated with day-to-day levels of activity, such as reading a book or navigating a busy city street. On the other end of the spectrum, delta waves are long and slow, associated with deep sleep. It’s the grey areas in the middle that seem to be at play in flotation.

EEG recordings have shown that during flotation beta and alpha waves decrease, while theta waves increase, patterns of brain activity typically associated with sleep or meditative states. While there are different distributions of brainwaves across different brain areas, decreasing beta and alpha waves are broadly associated with lowering states of arousal. And while theta waves occur throughout the brain during wakefulness, they characterize the first stage of sleep. Coupled with subjective reports about flotation, these patterns point toward a hypnogogic state, that liminal zone where conscious control of mental processes begins to loosen its grip, when you stop engaging with the outside world and turn inward, just before falling asleep.

The first flotation tank was built in the mid-1950s by a researcher who had a lifelong fascination with states of consciousness. John Lilly, a brilliant and wildly unorthodox researcher then studying sensory deprivation at the National Institute of Mental Health (NIMH), invented an upright flotation tank in which a subject could be fully submerged like a scuba diver. The suit he designed is reminiscent of scuba gear, with the addition of a rather terrifying-looking hood and blackout mask to restrict vision (see A Breath of Fresh Air).

 

A Breath of Fresh Air: The first experimental flotation tank designed by John Lilly completely immersed the subject underwater. Subjects wore a full-body suit much like scuba gear, with a special hood and black goggles to block sensory stimulation to the visual system. This setup proved far too anxiety-provoking, so Lilly redesigned the tank so subjects could float with their face out of the water, breathing freely.John Lilly/Columbia University Press

At first, Lilly experimented on himself and fellow researchers, and he quickly realized the discomfort and of the hood and the fear of drowning were aggravating distractions. He decided to ditch the suit and redesign the tank so a subject could float horizontally, with their face out of the water.

Lilly, who was friends with such luminaries as Richard Feynman and Buckminster Fuller, lost a great deal of credibility in the scientific community when he left NIMH to follow his own dubious research programs, which included taking massive amounts of LSD and Ketamine (sometimes while floating), giving LSD to dolphins, and trying to communicate with extraterrestrial life. “I took LSD for the first time, in the tank, with three dolphins under it in a sea pool. I was scared shitless,” wrote Lilly. “As I climbed over the wall into the saltwater, a memorandum, from N.I.M.H appeared before me: “Never take LSD alone.” That’s when I learned that fear can propel you in a rocketship to far out places.” And yet, Lilly may have been onto something.

Subsequent research suggests there are states of arousal that fall between conventionally categorized states such as sleep and waking, supporting his intuition that there are multiple states of human consciousness we have yet to fully explore. In the 1990s, the discovery of the Default Mode Network, an interconnected archipelago of brain areas whose activity decreases when we are focused on a task and increases when we stop focusing, complicated the notion that brain areas are either “on” or “off,” in use or on hold. And sleep, as anyone who has used the popular SleepCycle app knows, is composed of multiple levels of arousal serving many functions, which we have yet to fully understand. As veteran REST researcher Roderick Borrie puts it, “If you just look at brainwaves, it looks like the brain is asleep, but it’s not, which allows a different kind of processing to occur.”

“We had a Zen master come to my lab once,” Suedfeld told me, “and he asked us if we would let him float, so we did, of course. He came out and said, every day since I was very young, I meditate four or five hours a day, and the level of meditative depth that I experienced in the tank was such as I can only manage maybe once or twice a year.” Suedfeld, who coined the term REST with Borrie in the 1970s, has shown that restricted stimulus environments can reduce pain, ease headaches, and support behavior modification. Recently, he has used REST to help people quit smoking. He believes REST has clinical advantages over meditation. “You don’t have to learn how to do it,” he said. “You are in no danger of becoming addicted physically and you can’t overdose. If you have a bad experience all you have to do is get up and walk out.”

Highly experienced meditators show dramatic increases and synchronization in gamma waves, a type of brainwave even shorter and faster than beta waves, which have not been found in the brain during flotation. As Dr. Richard Davidson, a meditation researcher at the University of Madison-Wisconsin, put it, “Meditation is really designed to produce awakening, not sleep.” And there are many different meditation techniques. “Meditation is kind of like sports, some are more active, some are less active.” When I asked about mindfulness meditation, the practice most commonly compared to flotation, he said, “Mindfulness is classically described as paying attention non-judgmentally, and I doubt that participants in REST are given that instruction.”

Evidence for what happens during flotation remains elusive partly because after the 1960s, sensory deprivation was something of a dirty word, associated with Lilly’s less-than-scientific experimentation and the torture of political prisoners both at home and abroad. The research dissipated. “Hebb and others who were doing that kind of research were attacked as being complicit in torture,” said Suedfeld. He paused. “I know of several people doing that research who were physically attacked. One had his children threatened at school. They had their houses and automobiles vandalized, et cetera. So that drove quite a few people out of the field, not surprisingly.” Even today, the REST literature is plagued by small sample sizes, poor controls, and case studies that offer tantalizing if incomplete evidence.

But research may be picking up, due partly to the recent resurgence of commercial float centers like the one I visited in Chelsea, or the one recently installed in a yoga studio just 20 blocks uptown. In Sweden, researchers such as Annette Kjellgren, Sven Bood, and Torsten Norlander have been conducting larger, well-controlled studies that show REST is clinically effective on conditions such as stress, chronic pain, and hypertension. In the U.S., Justin Feinstein, a young clinical neuropsychologist at the Laureate Institute for Brain Research, is constructing a flotation lab that will, for the first time, allow investigation into changes in brain activity during flotation. He will use the Institute’s two fMRI scanners to record brain activity while subjects are floating. Once Feinstein’s lab is up and running, it will be one of only a few flotation research labs in the country, and the only one with fMRI scanning capability. “A lot of speculation goes on in the field,” he said, “but we just don’t know. A lot of this research has yet to be done.”

One of the biggest remaining mysteries is why people tend to have a similar progression of subjective experiences in the tank. Thomas Fine at the University of Toledo’s College of Medicine, whose research has shown that REST raises endorphins and lowers stress hormones, as well as offering relief from hypertension, rheumatoid arthritis, and pain, has encountered this progression many times in his work. He notes that people will have different experiences depending on different individual characteristics, such as sensitivity to external stimuli, but says, “Even John Lilly talked about people initially being aware of their body and the effect on the body, then when people got used to the tank, it was less about their body and more about their internal experience. It could be more about emotion or what their thoughts are, or the connection between those. Then as they float further, they go to no thought, just experience. That’s the level we think is related to the deep relaxation.” 

Was I waiting for an out-of body experience? For enlightenment?

Did I expect the private present tense to be so deafening? And then so quiet? When I stopped trying so hard to relax, what came over me was a calm more profound than anything I could have imagined.

I did not expect this, either: Once I was less distracted by the physical, my attention turned toward the mental, peeling back layer after layer of thought toward some white-hot core of emotion. When I began to cry, softly, the water responded, creating tiny wavelets that rocked my body at the center of the tank.

Near the end of my float, I noticed a new sound, soft and slightly distant. Not bothersome, but a constant hum with a flickering texture. I concentrated on this sound. Listened. Tried to name it. The best I could come up with was crickets. It sounded like a chirruping field of crickets, just across a two-lane road on a summer evening. It was lovely. Mesmerizing.

Afterward, when I asked Zeiger about the crickets, he nodded and said, “That’s the sound of your consciousness at work.” Zeiger had a tall glass of spicy iced tea waiting for me in his living room. It was the best thing I have ever tasted, which I know because I wrote this in my notebook—“the best thing I have ever tasted.” He sat across from me in an expensive ergonomic desk chair, wearing a pale blue shirt that matched his jeans and steady blue eyes, and all that undifferentiated blue made looking at him like looking at the sky—my eyes didn’t quite know where to focus.

I felt raw. A little dazed. Colors were a bit overwhelming. They say your senses are heighted afterward. As I blinked at Zeiger, trying to follow what he was saying, I was reminded that the sensory reduction techniques used by the CIA were designed to make prisoners more sensitive to the overstimulation that follows. At Guantanamo Bay, they have used bright lights and blared heavy metal from loudspeakers for days.

Outside, on West 23rd Street, everything was too bright, too loud, too fast. Text screamed from all sides. Signs for “News on 23rd” and takeout from “Wrapido.” A woman with short legs ran for a bus, and I watched her watch it pull away. In its wake, an old brick building with huge white letters in each window: “Joschi Yoga.” I thought about all the people inside, stretching and sweating and trying to calm their minds. A siren shrieked into life somewhere down the avenue, wailing high and bright.


~ Meehan Crist is writer in residence in Biological Sciences at Columbia University and editor-at-large at Nautilus. Her writing has appeared in publications such as The New York Times, The Los Angeles Times, The New Republic, The Believer, Scientific American and Science.


Additional Reading

Aftanas, L.I. & Golocheikine, S.A.Human anterior and frontal midline theta and lower alpha reflect emotionally positive state and internalized attention: high-resolution EEG investigation of meditation. Neuroscience Letters 310, 57-60 (2001).

Fine, T.H., & Turner, J.W., Jr. The use of restricted environmental stimulation therapy (REST) in the treatment of essential hypertension. First International Conference on REST and Self-Regulation, 136-143 IRIS Publications, Toledo, Ohio (1983).

Fine, T.H. & Turner, J.W. REST-assisted relaxation and chronic pain. Health and Clinical Psychology 4, 511-518 (1985).

Heron, W. The pathology of boredom. Scientific American 196, 52-56 (1957).

Iwata, K., Yamamoto, M., Nakao, M., & Kimura, M. A study on polysomnographic observations and subjective experiences under sensory deprivation. Psychiatry and Clinical Neurosciences 53, 129-131 (1999).

Iwata, K., Nakao, M., Yamamoto, M., & Kimura, M. Quantitative characteristics of alpha and theta EEG activities during sensory deprivation. Psychiatry and Clinical Neurosciences 55, 191-192 (2001).

Jacobs, G.D., Heilbronner, R.L., & Stanely, J.M. The effects of short term flotation REST on relaxation: a controlled study. Health Psychology 3, 99-112 (1984).

Kjaer, T.W., Law, I., Wiltschiotz, G., Paulson, O.B., & Madsen, P.L. Regional cerebral blood flow during light sleep—a H2 15O-PET study. Journal of Sleep Research 11, 201–207 (2002).

Klein, N. The Shock Doctrine Picador, New York (2007).

Solomon, P. et al. Sensory Deprivation: A Symposium Held and Harvard Medical School Harvard University Press, Cambridge (1961).

Lilly, J.C. Mental effects of reduction of ordinary levels of physical stimuli on intact healthy persons. Psychiatric Research Reports of the American Psychiatric Association 5, 10-28 (1956).

Lilly, J.C. & Gold, E.J. Tanks for the Memories: Flotation Tank Talks Gateway Books & Tapes (1996).

Lutz, A., Greischar, L.L., Rawlings, N.B., Ricard, M., & Davidson, R.J. Long-term meditators self-induce high-amplitude gamma synchrony during mental practice. PNAS 101, 16369-16373 (2004).

McCoy, A.W. A Question of Torture Henry Holt, New York (2006).

McGrady, A.V., Turner, J.W. Jr., Fine, T.H., & Higgins, J.T. Effects of biobehaviorally-assisted relaxation training on blood pressure, plasma renin, cortisol, and aldosterone levels in borderline essential hypertension. Clinical Biofeedback & Health 10, 16-25 (1987).

Murphy, C.W., Kurlents, E., Cleghorn R.A., & Hebb, D.O. Absence of increased corticoid excretion with the stress of perceptual deprivation. Canadian Journal of Biochemistry and Physiology 33,1062-1063 (1955).

Rzewnicki, R., Wallbaum, A.B.C., Steel, H., & Suedfeld, P. REST for muscle contraction headaches: A comparison of two REST environments combined with progressive muscle relaxation training. Restricted Environmental Stimulation: Research and Commentary 245-254 (1990).

Schacter, D.L. The hypnagogic state: a critical review of the literature. Psychological Bulletin 83, 452-481 (1976).

Suedfeld, P. The benefits of boredom: sensory deprivation reconsidered. American Scientist 63, 60-69 (1975).

Suedfeld, P. The clinical relevance of reduced sensory stimulation. Canadian Psychological Review/Psychologie canadienne 16, 88-103 (1975).

Turner, J.W. Jr. & Fine, T.H. Effects of relaxation associated with brief restricted environmental stimulation therapy (REST) on plasma cortisol, ACTH, and LH. Biofeedback and Self-Regulation 8, 115-126 (1983).

Turner, J.W. Jr., Fine, T., Ewy, G., Sershon, P., & Frelich, T. The presence or absence of light during flotation restricted environmental stimulation: Effects on plasma cortisol, blood pressure and mood. Biofeedback and Self-Regulation 14, 291-300 (1989).

Turner, J.W. Jr. & Fine, T.H. Hormonal changes associated with restricted environmental stimulation therapy. In Suedfeld, P., Turner, J., & Fine, T. (Eds.), Restricted environmental stimulation theoretical and empirical development in flotation REST Springer-Verlag, New York, N.Y. (1990).

Zubeck, J.P. Sensory Deprivation: Fifteen years of research N.Y. Appleton-Century-Crofts (1969).

Jeff Winkler - What Are the Benefits of Locking Yourself in a Tank and Floating in Room-Temperature Saltwater?

The benefits are pretty amazing in my experience, but I also had unlimited access to the tank and could float in each session for as long as I wanted. For about a year and a half of my time in grad school back in the early 1990s, I floated on average about once a week, sometimes much more, sometimes for 30 minutes up to as long as three hours, with music and without, sober and with a small dose of LSD on board.

Those experiences put me back in my body in a way nothing else ever had. It also woke me up to the depths of my own inner world and to the heights, as well. In one session I saw my death mask. In another session I was a tiny vulnerable body floating in the vastness of the Universe.

I was not a happy person at that point in my life. But after dozens of sessions in the tank I began to rediscover myself and the will to live.

THAT is the benefit (one of them, at least) of locking myself in a tank and floating in room-temperature saltwater.

What Are the Benefits of Locking Yourself in a Tank and Floating in Room-Temperature Saltwater?

By Jeff Winkler • July 29, 2014 • Pacific Standard


Isolation tank. (Photo: Wikimedia Commons)

After three sessions in an isolation tank, the answer’s still not quite clear.

•

“It’s almost better than therapy,” said the spa owner. We were sitting in the common room, which looked like a minimalist, high-class Chinese restaurant that prefers the word “cuisine.” Freshly washed and nibbling dark chocolate, I had just relayed a rather macabre vision from my first 90-minute “float.” My holistic spaman’s comment was not wholly appreciated.

Over the past few years, sensory deprivation tanks—you’re suspended in a few inches of body-temperature, epsom saltwater completely removed from light, sound, and touch—have gone quasi-mainstream. The goal is deceptively simple: Reducing external stimuli to an absolute minimum. Purposely striving for a state of purposelessness. Some say it provides a kind of natural buzz. Those who lack the dexterity for yoga and/or patience for sitting still in the lotus position say it helps them achieve a kenshō-grade meditative state. Others even suggest it has medicinal benefits.

I was skeptical. My last serious attempt at mediation did not go so well. But considering the circumstances surrounding that incident, I was confident things couldn’t get any worse this time around.

SCIENTIFIC STUDY INTO ISOLATION and sensory deprivation began in earnest in the 1950s, ground zero being McGill University in Montreal. The 1950s was a period of major laboratory efforts in the field of psychology, a shift from the couch to the IRL. This period of institutional experimentation saw the human mind being treated like silly putty, the least damaging results being incidents that sound like local emo bands: MKULtra, the Milgram Experiment, Zimbardo’s prison study. Initial isolation studies locked participants in four-star solitary confinement with amenities like complimentary white noise and comfy blindfold masks.

Dr. John C. Lilly developed the first floatation tank in 1954, its basic design still mostly unchanged today. A neuroscientist, Lilly had been working for the National Institutes of Health in areas like brain activity, cognition, and dolphin communication (he was Jane Goodall of the sea), when he created his invention. He’d come up with the idea for the tank after wondering, “What would happen to my mind if I freed myself from physical stimuli,” which is as close as there comes to a straight answer from Lilly regarding, well, anything. Lilly eventually moved to Florida, where he combined his work on the flotation tank with his studies of animal brain activity. Oh, right, and LSD.

Lilly began floating while dropping acid, claimed to conference with aliens from another dimension while in the tank, gave dolphins a “100 mcg dose” of his synthesized sacrament as part of his interspecies communication studies (Goodall = amateur), and occasionally took PCP bicycle rides (not a druggie euphemism). And as frequent drug users do, he talked about it. A lot. Of the 1960s hippie mafia that helped define the New Age stereotype, Lilly’s a top Don, and for the next 50-odd years he went exploring what he called innerspace.

I was more than ready for innerspace travel. But there were launch issues. Being inside the tank for the first time is so unnerving because it’s so unnatural. Your first time, it takes a while (15 minutes?) to adapt to floating on the saltwater like a fishing bob. There’s slight discomfort, your body knowing damn well this kind of prolonged and effortless physical suspension is not normal. Then there’s the isolation. Never mind cave divers, humans almost never experience this kind of almost complete aloneness. With absolutely no outside stimuli—even prisoners in solitary can scratch the walls—you’re confronted with the existential clown parade marching inside your own head.

How else to explain the macabre vision: floating in a void, having a disagreement with a bloodless, severed forearm that skittered over my body like a pesky spider. Annoyed, I tried to throw it into the darkness, but if came back like a magnet boomerang. This was the better-than-therapy my spaman was talking about.

PETER SUEDFELD BECAME THE TANK’s champion after Lilly. Suedfeld gave the experience a scientific name with mass appeal: Restricted Environmental Stimulation Technique. His numerous studies, as well as those of other REST enthusiasts, indicate that floatation tanks have positive effects on a plethora of issues: hypertension, child autism, smoking cessation, obesity, even PMS (so long as the woman experiences symptoms before entering the tank).

As with any cure-all, the studies are mostly inconclusive. And unlike Lilly’s alien meetings, the Suedfeld crowd has enough sense to direct most of the focus on the mental health benefits. From a psychological standpoint, REST reportedly improves concentration and creativity. More concretely, it allows people to organize their noise-filled lives, a power-nap for your senses. My spaman told me he has some weekly clients, several of whom are doctors and nurses who use the tank to clear the mental detritus after a three-day shift.

My second time in the tank, it took almost no time to get still, physically and mentally. I knocked idle thoughts away like soft pitches at batting practice. But every time I felt my “self” begin to disappear, I got excited. At those moments, I’d be pulled back into self consciousness, aware that I was lying naked in a saltwater tank that smelled a little of mildew. Clearly, I was doing something wrong. And, frankly, it was all rather stressful.

A vague sense of melancholy came at the end of the session, marked by the drowsy sounds of a didgeridoo track (perhaps this partially explains the severed boomerang). Imagine how you feel being snapped back to reality when a lover’s massage finally ends. Relaxed but glum. After nibbling dark chocolate in the common room for 10 minutes, I left. Outside, the colors weren’t brighter, the sounds weren’t clearer. Just before turning the key to my engine, only one thought came to mind: I’ve got to come back. I need this to work.

WHATEVER THE SCIENCE, REST clearly has a positive effect on a lot of well-to-do people. Early next month in Portland, the fourth annual Float Conference will take place. Float centers are popping up in just about every major city. If you can’t throw down $50 to $100 per session, put that money in a piggy bank because tanks are available for purchase—new, between $10,000 and $45,000, while previous-floated tanks go for about $5,000.

Joe Rogan, the former Fear Factor host and current UFC commentator, is often credited with tanks resurgent popularity. Rogan has been talking up float tanks for years, and not on a street corner; dude has a podcast. Even my spaman volunteered that the comedian is largely responsible for the tank’s recent popularity. The vanguard of the new REST movement, Rogan takes a little from Lilly’s philosophizing and a little from Suedfeld’s science. That is, while he espouses of the tank’s mind-altering, quasi-psychological benefits for creativity and insight, Rogan’s pre-tank regime is pretty straight-forward: “I like getting really baked.”

During my third and final session, I spent some time debating what would have been worse: showing up really baked or floating sober. The former so impolite, the latter so incredibly boring. Even my subconscious was twiddling thumbs. During a theta state, I “walked” out of the tank and had an out-of-body cigarette break before grudgingly returning to my terrestrial form. Mine was clearly not the kind of experience that supposedly helps with smoking cessation.

Nor did I see much improvement in other areas. My hypertension, for which REST is a supposed alleviant, did go down. For a day. Despite all the planning, the scheduling and the billing, everyone—the literature, my spaman—made it clear: Expect nothing and nothingness you can expect. It was maddening. I even considered doing a fourth session. Just one more taste. One more meditative short-cut, perfectly compartmentalized within a 90-minute session. I would spend my time in REST contemplating the nature REST itself. I would reach distant sectors of innerspace, maybe wave (respectively) to the alien overlords.

In the end, this seemed as unwise as acid tanking. The contemplative equivalent of mirror-on-mirror infinite regress. Or Googling “Google.” Trying to figure out where I went wrong, I kept going back to the meditative encounter from years ago. I’d spent a week at a Buddhist monastery on the outskirts of Kathmandu, one day shy, in fact, of shaving my head and going full monk. An unruly night, a sort of “last hoorah,” in a back-alley cathouse put an end to that plan, but I’ll never forget the training the head honcho had me doing that week. It involved walking a straight line, putting one foot in front of the other, concentrating all the energy into every movement until a sense of stillness and calm was achieved. Obviously, it didn’t work out as planned, but I’m keen on the idea. No shortcuts, no appointments, no “break” from the real world, no nothing. Just nirvana with each step. It’s not easy, but it’s free.

Jeff Winkler works as a writer in Texas. His efforts have appeared in Texas Monthly, Oxford American, The New Republic, Vice, and elsewhere. He tweets, sporadically. More From Jeff Winkler.

Michael Bond - How Extreme Isolation Warps the Mind

Michael Bond is the author of The Power of Others: Peer Pressure, Groupthink, and How the People Around Us Shape Everything We Do (2014). This article from the BBC is adapted from his book.

If you have ever tried a sensory deprivation tank, you have a glimpse of what isolation (from everything, including vision, sound, scent, taste, and touch) can do to the mind. In my first college stint, one of my housemates in Ashland (OR) had a sensory deprivation tank she used with massage clients. I spent as much time as possible in that tank, up to 3-4 hours, and once on a low-dose of LSD (about 100 mcgs). As much as anything else I have done in my life, including meditation and therapy, getting to know my own mind without any outside input began a process of change (and curisoity) in me that continues today. If it were feasible, I'd buy a tank.

This article looks at isolation in a bigger sense, however, including prisoners in solitary confinement and those who have participated in research that removes them from circadian rhythms of light and dark.

This is a fascinating article, so take a few minutes to check it out, then go see the other cool stuff that the BBC Future has made available (finally) to web users in the States.

How Extreme Isolation Warps the Mind

When people are isolated from human contact, their mind can do some truly bizarre things, says Michael Bond. Why does this happen?

Michael Bond | 14 May 2014

(Getty Images)

Sarah Shourd’s mind began to slip after about two months into her incarceration. She heard phantom footsteps and flashing lights, and spent most of her day crouched on all fours, listening through a gap in the door.

That summer, the 32-year-old had been hiking with two friends in the mountains of Iraqi Kurdistan when they were arrested by Iranian troops after straying onto the border with Iran. Accused of spying, they were kept in solitary confinement in Evin prison in Tehran, each in their own tiny cell. She endured almost 10,000 hours with little human contact before she was freed. One of the most disturbing effects was the hallucinations.

“In the periphery of my vision, I began to see flashing lights, only to jerk my head around to find that nothing was there,” she wrote in the New York Times in 2011. “At one point, I heard someone screaming, and it wasn’t until I felt the hands of one of the friendlier guards on my face, trying to revive me, that I realised the screams were my own.”

We all want to be alone from time to time, to escape the demands of our colleagues or the hassle of crowds. But not alone alone. For most people, prolonged social isolation is all bad, particularly mentally. We know this not only from reports by people like Shourd who have experienced it first-hand, but also from psychological experiments on the effects of isolation and sensory deprivation, some of which had to be called off due to the extreme and bizarre reactions of those involved. Why does the mind unravel so spectacularly when we’re truly on our own, and is there any way to stop it?

Inside prison walls, solitude can play disturbing tricks on the mind (Flickr/Cyri)

We’ve known for a while that isolation is physically bad for us. Chronically lonely people have higher blood pressure, are more vulnerable to infection, and are also more likely to develop Alzheimer’s disease and dementia. Loneliness also interferes with a whole range of everyday functioning, such as sleep patterns, attention and logical and verbal reasoning. The mechanisms behind these effects are still unclear, though what is known is that social isolation unleashes an extreme immune response – a cascade of stress hormones and inflammation. This may have been appropriate in our early ancestors, when being isolated from the group carried big physical risks, but for us the outcome is mostly harmful.

Yet some of the most profound effects of loneliness are on the mind. For starters, isolation messes with our sense of time. One of the strangest effects is the ‘time-shifting’ reported by those who have spent long periods living underground without daylight. In 1961, French geologist Michel Siffre led a two-week expedition to study an underground glacier beneath the French Alps and ended up staying two months, fascinated by how the darkness affected human biology. He decided to abandon his watch and “live like an animal”. While conducting tests with his team on the surface, they discovered it took him five minutes to count to what he thought was 120 seconds.

A similar pattern of ‘slowing time’ was reported by Maurizio Montalbini, a sociologist and caving enthusiast. In 1993, Montalbini spent 366 days in an underground cavern near Pesaro in Italy that had been designed with Nasa to simulate space missions, breaking his own world record for time spent underground. When he emerged, he was convinced only 219 days had passed. His sleep-wake cycles had almost doubled in length. Since then, researchers have found that in darkness most people eventually adjust to a 48-hour cycle: 36 hours of activity followed by 12 hours of sleep. The reasons are still unclear.

After emerging from a nine week stint in underground darkness, Michel Siffre needed to wear a blindfold to protect his eyes (Getty Images)

As well as their time-shifts, Siffre and Montalbini reported periods of mental instability too. But these experiences were nothing compared with the extreme reactions seen in notorious sensory deprivation experiments in the mid-20th Century.

In the 1950s and 1960s, China was rumoured to be using solitary confinement to “brainwash” American prisoners captured during the Korean War, and the US and Canadian governments were all too keen to try it out. Their defence departments funded a series of research programmes that might be considered ethically dubious today.

The most extensive took place at McGill University Medical Center in Montreal, led by the psychologist Donald Hebb. The McGill researchers invited paid volunteers – mainly college students – to spend days or weeks by themselves in sound-proof cubicles, deprived of meaningful human contact. Their aim was to reduce perceptual stimulation to a minimum, to see how their subjects would behave when almost nothing was happening. They minimised what they could feel, see, hear and touch, fitting them with translucent visors, cotton gloves and cardboard cuffs extending beyond the fingertips. As Scientific American magazine reported at the time, they had them lie on U-shaped foam pillows to restrict noise, and set up a continuous hum of air-conditioning units to mask small sounds.

After only a few hours, the students became acutely restless. They started to crave stimulation, talking, singing or reciting poetry to themselves to break the monotony. Later, many of them became anxious or highly emotional. Their mental performance suffered too, struggling with arithmetic and word association tests.

Sensory deprivation can cause hallucinations - sometimes starting with geometric shapes or points of light, and then getting stranger... (Akuei/Flickr)

But the most alarming effects were the hallucinations. They would start with points of light, lines or shapes, eventually evolving into bizarre scenes, such as squirrels marching with sacks over their shoulders or processions of eyeglasses filing down a street. They had no control over what they saw: one man saw only dogs; another, babies.

Some of them experienced sound hallucinations as well: a music box or a choir, for instance. Others imagined sensations of touch: one man had the sense he had been hit in the arm by pellets fired from guns. Another, reaching out to touch a doorknob, felt an electric shock.

When they emerged from the experiment they found it hard to shake this altered sense of reality, convinced that the whole room was in motion, or that objects were constantly changing shape and size.

Distressing end

The researchers had hoped to observe their subjects over several weeks, but the trial was cut short because they became too distressed to carry on. Few lasted beyond two days, and none as long as a week. Afterwards, Hebb wrote in the journal American Psychologist that the results were “very unsettling to us… It is one thing to hear that the Chinese are brainwashing their prisoners on the other side of the world; it is another to find, in your own laboratory, that merely taking away the usual sights, sounds, and bodily contacts from a healthy university student for a few days can shake him, right down to the base.”

In 2008, clinical psychologist Ian Robbins recreated Hebb’s experiment in collaboration with the BBC, isolating six volunteers for 48 hours in sound-proofed rooms in a former nuclear bunker. The results were similar. The volunteers suffered anxiety, extreme emotions, paranoia and significant deterioration in their mental functioning. They also hallucinated: a heap of 5,000 empty oyster shells; a snake; zebras; tiny cars; the room taking off; mosquitoes; fighter planes buzzing around.

A clip from BBC Horizon’s Total Isolation experiment – read more information about the programme here.

Why does the perceptually deprived brain play such tricks? Cognitive psychologists believe that the part of the brain that deals with ongoing tasks, such as sensory perception, is accustomed to dealing with a large quantity of information, such as visual, auditory and other environmental cues. But when there is a dearth of information, says Robbins, “the various nerve systems feeding in to the brain’s central processor are still firing off, but in a way that doesn’t make sense. So after a while the brain starts to make sense of them, to make them into a pattern.” It creates whole images out of partial ones. In other words, it tries to construct a reality from the scant signals available to it, yet it ends up building a fantasy world.

Such mental failures should perhaps not surprise us. For one thing, we know that other primates do not fare well in isolation. One of the most graphic examples is psychologist Harry Harlow’s experiments on rhesus macaque monkeys at the University of Wisconsin-Madison during the 1960s, in which he deprived them of social contact after birth for months or years. They became, he observed, “enormously disturbed” even after 30 days, and after a year were “obliterated” socially, incapable of interaction of any kind. (A comparable social fracturing has been observed in humans: consider the children rescued from Romanian orphanages in the early 1990s, who after being almost entirely deprived of close social contact since birth grew up with serious behavioural and attachment issues.)

We may crave solitude occasionally, but in the long term it's not good for us physically or mentally (Getty Images)

Secondly, we derive meaning from our emotional states largely through contact with others. Biologists believe that human emotions evolved because they aided co-operation among our early ancestors who benefited from living in groups. Their primary function is social. With no one to mediate our feelings of fear, anger, anxiety and sadness and help us determine their appropriateness, before long they deliver us a distorted sense of self, a perceptual fracturing or a profound irrationality. It seems that left too much to ourselves, the very system that regulates our social living can overwhelm us.

Take the 25,000 inmates held in “super-maximum security” prisons in the US today. Without social interaction, supermax prisoners have no way to test the appropriateness of their emotions or their fantastical thinking, says Terry Kupers, a forensic psychiatrist at the Wright Institute in Berkeley, California, who has interviewed thousands of supermax prisoners. This is one of the reasons many suffer anxiety, paranoia and obsessive thoughts. Craig Haney, a psychologist at the University of California, Santa Cruz, and a leading authority on the mental health of inmates in the US, believes that some of them purposefully initiate brutal confrontations with prison staff just to reaffirm their own existence – to remember who they are.

Coping strategy

Social isolation is not always debilitating, however. Are some better than others at coping? And can you train yourself to resist the worst effects? Here scientists have fewer hard answers, but we can at least look to the lessons of individuals who thrived – or floundered – under isolation.

When Shourd was imprisoned in Iran, she was arguably among the least-equipped people to cope, because her incarceration came out of the blue. People in her circumstances have their world suddenly inverted, and there is nothing in the manner of their taking – no narrative of sacrifice, or enduring for a greater good – to help them derive meaning from it. They must somehow find meaning in their predicament – or mentally detach themselves from their day-to-day reality, which is a monumental task when alone.

Hussain Al-Shahristani managed it. He was Saddam Hussein’s chief nuclear adviser before he was tortured and shut away in Abu Ghraib prison near Baghdad after refusing on moral grounds to cooperate on the development of an atomic weapon. He kept his sanity during 10 years of solitary confinement by taking refuge in a world of abstractions, making up mathematical problems which he then tried to solve. He is now deputy energy minister of Iraq. Edith Bone, a medical academic and translator, followed a similar strategy during the seven years she spent imprisoned by the Hungarian communist government after World War Two, constructing an abacus out of stale bread and counting out an inventory of her vocabulary in the six languages she spoke fluently.

Some believe a military background may help prevent the worst effects of isolation (Thinkstock)

Such experiences may be easier to take if you belong to a military organisation. Keron Fletcher, a consultant psychiatrist who has helped debrief and treat hostages, says mock detention and interrogation exercises of the kind he himself underwent while serving with the Royal Air Force are a good preparation for the shock of capture. “They teach you the basics of coping,” he says. “Also, you know your buddies will be busting a gut to get you back in one piece. I think the military are less likely to feel helpless or hopeless. Hopelessness and helplessness are horrible things to live with and they erode morale and coping ability.”

US senator John McCain is a good example of how a military mindset bestows psychological advantages. His five-and-a-half years as a prisoner of war in Vietnam, during which he refused to yield to his interrogators, actually seemed to strengthen him. Though note what he had to say about the two years he spent in isolation: “It’s an awful thing, solitary. It crushes your spirit and weakens your resistance more effectively than any other form of mistreatment… The onset of despair is immediate, and it is a formidable foe.”

Extreme reality

Psychologists who study how people cope with isolation have learnt much from solo explorers and mountaineers. For many adventurers deprived of human company – albeit voluntarily – the landscape itself can serve as an effective surrogate, drawing them out of themselves into the beauty or grandeur of their surroundings. Norwegian psychologist Gro Sandal at the University of Bergen in Norway, who has interviewed many adventurers about how they cope in extreme environments, says that transcending the reality of their situation in this way is a common coping mechanism. “It makes them feel safer. It makes them feel less alone.”

A similar psychological mechanism could explain why shipwrecked mariners marooned on islands have been known to anthropomorphise inanimate objects, in some cases creating a cabal of imaginary companions with whom to share the solitude. It sounds like madness but is likely a foil against it. Take the way sailor Ellen MacArthur nicknamed her trimaran “Mobi”, during her record-breaking solo circumnavigation of the globe in 2005. During the voyage she signed emails to her support team “love e and mobi”, and in her published account uses “we” rather than “I”.

Sailors have been known to combat the loneliness of the ocean by anthropomorphising inanimate objects (Thinkstock)

There is no more poignant illustration of the power of solitude to sink one person while lifting up another than the stories of Bernard Moitessier and Donald Crowhurst, two of the competitors in the 1968 Sunday Times Golden Globe round-the-world yacht race. The trophy, offered to the first sailor to complete a solo non-stop circumnavigation of the globe, was won in 313 days by Robin Knox-Johnston, the only one out of nine starters to finish. He seemed to relish being alone with his boat, but not as much as Moitessier, an ascetic Frenchman who practised yoga on deck and fed cheese to the shearwater birds that shadowed him. Moitessier found the experience so fulfilling, and the idea of returning to civilisation so distasteful, that he abandoned the race despite a good chance of victory and just kept on sailing, eventually landing in Tahiti after travelling more than halfway round the world again. “I continue non-stop because I am happy at sea,” he declared, “and perhaps because I want to save my soul.”

Crowhurst, meanwhile, was in trouble from the start. He left England ill-prepared and sent fake reports about his supposed progress through the southern seas while never actually leaving the Atlantic. Drifting aimlessly for months off the coast of South America, he became increasingly depressed and lonely, eventually retreating to his cabin and consolidating his fantasies in a rambling 25,000-word philosophical treatise before jumping overboard. His body was never found.

What message can we take from these stories of endurance and despair? The obvious one is that we are, as a rule, considerably diminished when disengaged from others. Isolation may very often be the “sum total of wretchedness”, as the writer Thomas Carlyle put it. However, a more upbeat assessment seems equally valid: it is possible to connect, to find solace beyond ourselves, even when we are alone. It helps to be prepared, and to be mentally resilient. But we shouldn’t underestimate the power of our imagination to knock over prison walls, penetrate icy caves or provide make-believe companions to walk with us.

This article is based on the book The Power of Others by Michael Bond (Oneworld Publications).

io9 - Everything You Ever Wanted to Know about Sensory Deprivation Tanks

I was fortunate during my first stint in grad school to have a roommate who owned a sensory deprivation tank - we just called it the float tank. I did many sessions in that watery cave, some of them simply using breath meditations, some using holotropic breathwork techniques, and some using ethneogens.

On more than one occasion I came out of the tank feeling incoherent (in a rational sense) and dissociative. But given the chance, I would do it again in an instant - no hesitation. It's a phenomenal tool for exploring inner space. 

Everything You Ever Wanted to Know about Sensory Deprivation Tanks

By Robert T. Gonzalez
August  12, 2011
 
On Fringe, a sensory deprivation tank can activate your mental powers and even open a gateway to another universe. But what can floating in a dark warm tank do for you in real life? And why would people even want to do such a thing?

The sensory deprivation tank — a temperature-regulated, salt-water filled, soundproof, lightproof tank that can isolate its occupant from numerous forms of sensory input all at once — has gone by many names over the years, but its overall design and purpose have remained largely unchanged: to find out what your brain does when it's shoved into a box all by itself and left alone for a while. Here's the complete lowdown on sensory deprivation tanks.

Back in the old days, if you wanted to experience sensory deprivation you wore a blindfold or stuck your fingers in your ears like everybody else. But that all changed in 1954, when neuroscientist John C. Lilly dared to question what would happen if the mind was deprived of as much external stimulus as possible.



In the original deprivation tank, you were suspended in 160 gallons of water with everything but the top of your head completely submerged. A nightmarish-looking "black-out" mask, similar to the ones pictured here, supplied you with air and blocked any light from reaching your eyes. The water and air temperature were kept at the same temperature as your skin, roughly 34 degrees celsius.

The masks were eventually done away with (apparently people found having their heads wrapped in latex distracting), and the requirement of total submersion along with them; instead, the water was saturated with 800 pounds of Epsom salt, which made the water so dense that you could float with your entire body at or near its surface in spite of its shallow depth.



Inside the tank there is no light, and therefore no sense of vision. You experience the kind of quiet that allows you to hear your muscles tense, your heart beat, and your eyelids close. The extreme buoyancy of the water lends your environment an almost zero-gravity quality. The lack of a temperature differential plays with your ability to perceive where your body ends and where the water and air begin.

But then what happens? What do people experience while they're in the tank? Can an isolation chamber really transport you to a parallel universe like it does on Fringe?

Read the rest of the article.