isolation tank

The tank is filled with {{Convert|10|in|cm}} of water which contains enough dissolved Epsom salt to create a specific gravity of approximately 1.25–1.26, enabling a person to float freely with their face above the water. In order to reduce thermal sensations, the water in the float tank is maintained at approximately skin temperature, around 35 °C. One typically floats without clothing to minimize tactile sensations, and earplugs are worn during floating both to minimize auditory sensations and to keep Epsom salt out of the ear canal.

File:Floatation REST.jpg float pool at the Laureate Institute for Brain Research in Tulsa, Oklahoma, USA allows subjects with clinical anxiety to float comfortably, without the apprehension one might encounter in an enclosed float environment.]]

Several different tank designs exist. Pod and cabin designs utilize enclosures with doors to enter or exit the tank, whereas pool designs are built from circular fiberglass and lack an enclosure to reduce the risk of claustrophobia. The pool design is housed in a room that is soundproof and lightproof, with tightly controlled ambient air temperature and humidity.

The isolation tank was developed in 1954 by John C. Lilly, a medical practitioner and neuropsychiatrist.{{cite journal| vauthors = Black D |date=December 10, 1979|title=Lie down in darkness|journal=New York Magazine|volume=12|issue=48|pages=60|issn=0028-7369}}{{cite book| vauthors = Gelb M, Caldicott SM |title=Innovate Like Edison|url=https://archive.org/details/isbn_9780525950318|url-access=limited|publisher=Dutton|year=2007|pages=[https://archive.org/details/isbn_9780525950318/page/140 140]|isbn=978-0-525-95031-8}}{{cite book| vauthors = Lilly JC |title=The Scientist: A Metaphysical Autobiography|publisher=Ronin Publishing|year=1996|edition=3|pages=[https://archive.org/details/scientist00lill/page/102 102]|isbn=0-914171-72-0|url-access=registration|url=https://archive.org/details/scientist00lill/page/102}} During his training in psychoanalysis at the US National Institute of Mental Health (NIMH), Lilly experimented with sensory deprivation.{{Cite journal|last=Phillips|first=Matthew T.|title=The Sensory Deprivation Tank – A Time Machine|url=https://onlinelibrary.wiley.com/doi/abs/10.1111/anoc.12138|journal=Anthropology of Consciousness|year=2021|volume=33 |pages=63–78 |language=en|doi=10.1111/anoc.12138|s2cid=237710164|issn=1556-3537|url-access=subscription}}

Widespread commercial interest and use of the isolation tank did not occur until 1972, when Glenn Perry, a computer systems programmer, began selling the first commercial tanks after he attended a five-day workshop by Lilly.{{Cite web|url=https://www.menshealth.com/fitness/a19546617/sensory-deprivation-tanks/|title=What Is Floating? Inside the Fitness Trend That Steph Curry and Joe Rogan Swear By| vauthors = deBara D |date=2018-01-17|website=Men's Health|language=en-US|access-date=2019-07-06}}

In 1981, there were about $4 million in sales and rentals in the industry, and expectations were that the market would grow, spurred by the film Altered States (a film starring William Hurt as a psychopathologist experimenting with a flotation tank), which came out in 1980.{{cite news | vauthors = |title=Relaxation Tanks: A Market Develops|url=https://www.nytimes.com/1981/11/21/business/relaxation-tanks-a-market-develops.html|work=The New York Times|date=21 November 1981}} According to one source in the industry, in the 1980s the rise of AIDS and the fear of shared water reduced demand for flotation centers. By 2013, flotation was more popular in Europe than the US, but had undergone some growth in the area around San Francisco; at that time a low-end tank cost about $10,000, and an hour-long flotation session cost about $70.{{cite news| vauthors = Efrati A |title=Float Centers Gaining Steam|url=https://www.wsj.com/articles/SB10001424127887324338604578326143828290394|newspaper=The Wall Street Journal|date=27 February 2013|access-date=May 15, 2013}}

Use of the float tank has roots in alternative medicine, where its use and promotion occurred largely outside of a scientific framework. Early scientific research on the use of float tanks was stalled by "political activists [who] viewed sensory deprivation as analogous to solitary confinement and torture", thus leading to "hostile publications in the popular media and in professional journals [and] to actual physical violence against researchers."{{Cite journal |last=Griffith |first=Ivan |date=2023 |title=Stepping Away from Sensory Deprivation: An Analysis of Floatation-REST Research |url=https://escholarship.org/uc/item/1k0828k4 |journal=UC Merced Undergraduate Research Journal |language=en |volume=15 |issue=1 |doi=10.5070/M415160862|doi-access=free }}{{Cite journal |last1=Suedfeld |first1=Peter |last2=Coren |first2=Stanley |date=January 1989 |title=Perceptual isolation, sensory deprivation, and rest: Moving introductory psychology texts out of the 1950s. |url=http://doi.apa.org/getdoi.cfm?doi=10.1037/h0079795 |journal=Canadian Psychology / Psychologie Canadienne |language=en |volume=30 |issue=1 |pages=17–29 |doi=10.1037/h0079795 |issn=1878-7304|url-access=subscription }}

Flotation has been widely advertised as a form of alternative medicine that has a number of health benefits, but the claims are often exaggerated and poorly evidenced.{{cite journal |vauthors=Jonsson K, Kjellgren A |title=Curing the sick and creating supermen: How relaxation in flotation tanks is advertised online |journal=European Journal of Integrative Medicine |volume=6 |issue=5 |year=2014 |pages=601–609 |issn=1876-3820 |doi=10.1016/j.eujim.2014.05.005|doi-access=free }} Despite the lack of scientific support, people have sought treatment from flotation for many conditions including muscle tension, chronic pain, hypertension, and rheumatoid arthritis to PMS.{{Cite news|url=http://www.bbc.co.uk/news/magazine-35521560|title=Why do people use flotation tanks?|date=2016-02-09|newspaper=BBC News Magazine|language=en-GB|access-date=2016-09-23}}

A 2005 meta-analysis of clinical trials that had been conducted at that time, found that the trials were generally small and highly prone to error, but given that limitation, use of isolation tanks, (called "flotation REST" or "restricted environmental stimulation therapy" in the literature) shows a large effect size (Cohen's d = 1.02) for stress reduction.{{cite journal|last1=van Dierendonck|first1=Dirk|title=Flotation restricted environmental stimulation therapy (REST) as a stress-management tool: A meta-analysis|journal=Psychology & Health|date=2005|volume=20|issue=3|pages=405–412|doi=10.1080/08870440412331337093|url=http://dx.doi.org/10.1080/08870440412331337093|url-access=subscription}} A 2018 review described flotation-REST as one of "[s]everal emerging technologies [which] may have relevance for interoception and mental health" as it "appears to noninvasively enhance exposure to interoceptive sensations such as the breath and heartbeat".{{Cite journal |last1=Khalsa |first1=Sahib S. |last2=Adolphs |first2=Ralph |last3=Cameron |first3=Oliver G. |last4=Critchley |first4=Hugo D. |last5=Davenport |first5=Paul W. |last6=Feinstein |first6=Justin S. |last7=Feusner |first7=Jamie D. |last8=Garfinkel |first8=Sarah N. |last9=Lane |first9=Richard D. |last10=Mehling |first10=Wolf E. |last11=Meuret |first11=Alicia E. |last12=Nemeroff |first12=Charles B. |last13=Oppenheimer |first13=Stephen |last14=Petzschner |first14=Frederike H. |last15=Pollatos |first15=Olga |date=2018-06-01 |title=Interoception and Mental Health: A Roadmap |journal=Biological Psychiatry: Cognitive Neuroscience and Neuroimaging |language=en |volume=3 |issue=6 |pages=501–513 |doi=10.1016/j.bpsc.2017.12.004 |pmid=29884281 |pmc=6054486 |issn=2451-9022|hdl=20.500.11850/282635 |hdl-access=free }}

Scientific research with float tank therapy generally uses the term "flotation-REST" (reduced environmental stimulation therapy) to refer to the technique.{{Cite journal| vauthors = Suedfeld P, Metcalfe J, Bluck S |date=1987-09-01|title=Enhancement of scientific creativity by flotation rest (restricted environmental stimulation technique)|url=https://www.sciencedirect.com/science/article/pii/S0272494487800312|journal=Journal of Environmental Psychology|language=en|volume=7|issue=3|pages=219–231|doi=10.1016/S0272-4944(87)80031-2|issn=0272-4944|url-access=subscription}}{{cite journal | vauthors = Feinstein JS, Khalsa SS, Yeh HW, Wohlrab C, Simmons WK, Stein MB, Paulus MP | title = Examining the short-term anxiolytic and antidepressant effect of Floatation-REST | journal = PLOS ONE | volume = 13 | issue = 2 | pages = e0190292 | date = 2018-02-02 | pmid = 29394251 | doi = 10.1371/journal.pone.0190292 | pmc = 5796691 | bibcode = 2018PLoSO..1390292F | doi-access = free }} This term is preferred over "sensory deprivation" due to the fact that 1) the float tank experience actually enhanced sensory input from the body (e.g., cardiorespiratory sensations) and can also be conceptualized as a form of sensory enhancement{{cite journal | vauthors = Feinstein JS, Khalsa SS, Yeh H, Al Zoubi O, Arevian AC, Wohlrab C, Pantino MK, Cartmell LJ, Simmons WK, Stein MB, Paulus MP | display-authors = 6 | title = The Elicitation of Relaxation and Interoceptive Awareness Using Floatation Therapy in Individuals With High Anxiety Sensitivity | journal = Biological Psychiatry. Cognitive Neuroscience and Neuroimaging | volume = 3 | issue = 6 | pages = 555–562 | date = June 2018 | pmid = 29656950 | doi = 10.1016/j.bpsc.2018.02.005 | pmc = 6040829 | doi-access = free }} and 2) the term "sensory deprivation" carries negative connotations of torture and hallucinations that have likely impeded legitimate research in this field.

• Aaron Traywick, an American businessman and life extension activist, drowned in an isolation tank in 2018. An autopsy found evidence of Ketamine in his system.{{Cite news|url=https://www.bloomberg.com/news/articles/2018-06-29/autopsy-reveals-biohacker-traywick-died-from-accidental-drowning|title=It Wasn't Biohacking That Killed the Biohacker: He Drowned|work=Bloomberg.com|access-date=July 2, 2018|language=en}}
• Carl Lawson, football player for the Dallas Cowboys, and formerly the New York Jets and Cincinnati Bengals, uses the tank for muscle recovery and visual training.{{Cite web | vauthors = Terrell K |url=https://www.espn.com/blog/cincinnati-bengals/post/_/id/28549|title=How do some NFL players relax before games? They float|date=2017-10-28|website=ESPN.com|language=en|access-date=2019-07-06}}
• Carl Lewis, track and field athlete, used in-tank visualization techniques to prepare himself for his gold medal long jump at the 1988 Seoul Olympics.{{Cite web | author = UrReporter |url=http://ireport.cnn.com/docs/DOC-804100|title=Flotation Tanks, Three Powerful Healing Therapies in One!|website=CNN iReport|access-date=2016-09-23|archive-url=https://web.archive.org/web/20160924021018/http://ireport.cnn.com/docs/DOC-804100|archive-date=2016-09-24|url-status=dead}}
• During Super Bowl XLIX, both NFL teams (the New England Patriots and Seattle Seahawks) rented out a local float spa during the week of the event. One team would float in the morning and the other would float in the afternoon.{{cite web | date = 26 July 2019 | vauthors = Sieker R | work = Float Therapy LLC | title = Why Athletes Benefit from Float Therapy | url = https://floattherapy.com/why-athletes-benefit-from-float-therapy/ | archive-url = https://web.archive.org/web/20190729192350/https://floattherapy.com/why-athletes-benefit-from-float-therapy/ | archive-date = 29 July 2019 }}
• Christof Koch, a neuroscientist known for his work on consciousness, states that he had "what some people call a mystical experience" in a float tank in Singapore.{{Citation |title=✂️ Esteemed neuroscientist Christof Koch describes his mystical experience in a float tank in Singapore to Lex Fridman. |url=https://www.youtube.com/clip/UgkxWiBFHOxu0hJM-ysA6ViyE1VmRec6vHEY |language=en |access-date=2022-07-19}}{{Cite book |last=Koch |first=Christof |title=The feeling of life itself: why consciousness is widespread but can't be computed |publisher=MIT Press |year=2019}}
• Joe Rogan has stated in his podcast on numerous occasions that he owns an isolation tank and credits it for allowing a state of deeper meditation.
• John Lennon treated his heroin addiction in 1979 with the help of 90-minute floats in a cedar-wood box.{{Dubious|date=November 2019}}
• Marvin Jones, wide receiver for the Jacksonville Jaguars and formerly of the Cincinnati Bengals and Detroit Lions, began using flotation therapy to help him in his recovery from an ankle injury while in Cincinnati.{{cite web | title = An interview with Marvin Jones | work = Zen Float Company | url = https://zenfloatco.com/floating-for-athletic-performance/| archive-url = https://web.archive.org/web/20160409115601/http://www.zenfloatco.com/floating-for-athletic-performance/| url-status = usurped| archive-date = April 9, 2016}}
• Phil Lester visited a flotation center for a YouTube video on his channel "AmazingPhil" on February 17, 2020.{{cite web | title = I Tried Floating In a Sensory Deprivation Tank For 3 Hours | url = https://www.youtube.com/watch?v=iPLPkbf9DaQ/ | work = YouTube | date=17 February 2020 }}
• Richard Feynman, Nobel Prize-winning physicist, discussed his experiences with isolation tanks in Surely You're Joking, Mr. Feynman!{{cite news| vauthors = Cole KC |title=Book Review: Surely you're joking Mr Feynman|url=https://www.nytimes.com/books/97/09/21/reviews/feynman-joking.html|work=The New York Times|date=January 27, 1985}}
• Several NFL teams, including the New England Patriots, Los Angeles Rams, and New Orleans Saints reportedly use floating as a way to increase players' quality of sleep as well as help with recovery.{{cite magazine | vauthors = Orr C | date = 1 February 2019 | magazine = Sports Illustrated | title = The Wild Story of How Bill Belichick Discovered the Benefits of Sleep Floatation Tanks | url = https://www.si.com/nfl/2019/02/01/patriots-sleep-float-tanks-bill-belichick-josh-mcdaniels-tom-brady/}}
• In 2015 two-time NBA MVP Stephen Curry reportedly used a sensory-deprivation tank every two weeks.{{cite news| vauthors = Alipour S |title=Stephen Curry on copying the Warriors' way: 'You won't have the personnel' |url= http://www.espn.com/nba/story/_/id/14314860/stephen-curry-small-ball-mj-gunning-record-books|access-date=13 December 2016|agency=ESPN|date=8 December 2015}}

• Dark retreat
• Mindfulness
• Prisoner's cinema
• Psychedelic experience

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{{DEFAULTSORT:Isolation Tank}}

Category:Alternative medical treatments

Category:Experimental psychology

Category:Devices to alter consciousness