Floatation-REST · isolation tank · salt hour
Nine channels went quiet.
Cut the nine channels and the alarm has less to ride.
I booked a tank because a reel said the field would talk in the dark, and I got still water and a quieter chest.
An eight-foot circle of salt
Tulsa. Open pool. One hour.
Feinstein and the Laureate Institute group printed the hour in PLoS ONE, 2018, 13(2):e0190292, DOI 10.1371/journal.pone.0190292, after a first sit in an open circular pool at the Float Clinic in Tulsa, Oklahoma, with staff on an intercom and a locked door. Fifty people who had never floated sat that protocol, sixteen of them men and thirty-four of them women, mean age 36.8 with a spread of 10.9 years, ages 18 to 55 on the inclusion sheet.
The pool was eight feet across and held eleven inches of reverse-osmosis water, and about 1,800 pounds of Epsom salt sat in that water at a specific gravity of 1.25 to 1.26, so a body floated on its back with the face above the line and the ears just under it. Water held 95.0 F plus or minus 0.3. Air at the rim held 93.5 F plus or minus 0.5.
The methods named nine channels they tried to quiet, from sight and sound down through smell and taste, then heat and touch, then balance plus gravity plus body position, and they asked for stillness and almost no speech. They could leave whenever they wanted. Forty-eight people stayed the hour.
Every chest dropped
All fifty STAI scores fell.
The primary outcome was the Spielberger State Anxiety Inventory, twenty items scored from 20 to 80, rated as right now about thirty minutes before the hour and again about thirty minutes after it, and they were told not to rate the hour itself on the second pass. Every chest dropped. Group test t(49) = -15.16, p < .0001, d = 2.15.
Forty-six people also carried unipolar depression. Twenty sat on an SSRI or SNRI. Eight had a benzodiazepine on the sheet, and none of them took one that day.
Twenty-six people carried generalized anxiety, and sixteen carried social anxiety. Panic sat on twelve sheets while agoraphobia sat on eight and PTSD sat on seventeen.
On the day they floated, mean OASIS sat at 9.6 and mean PHQ-9 sat at 11.4, with perceived stress at 25.7, ASI-3 at 26.6, and disability at 13.5. Net-time happiness sat at -7.3. Seventeen people still met the strict ASI-3 of 30 or more plus OASIS of 8 or more that morning, and that subgroup brought the largest moves.
Stress fell with muscle tension, and pain dropped on the same pass. Negative affect fell. Serenity rose at d = 2.11, and feeling refreshed rose at d = 2.39. The paper says muscle tension moved the most of the sixteen scales they ran.
Open-label. No anxious control arm. How long the quiet lasts after you stand up is unknown.
The light could stay on
The alarm drop held with the blue LED lit.
Twenty-four people kept the light on for most of the hour and sat in the dark for 2.1 minutes on average. Twenty-six killed the light and sat in the dark for 53.4 minutes.
The STAI drop stayed huge either way, d = 2.19 with the light and d = 2.15 without it. Serenity moved less with the light on, d = 1.79 against 2.51, while well-being sat at d = 0.78 against 1.39 and stress sat at d = -0.95 against -1.72. Negative affect sat at d = -0.65 against -1.05.
That is the one contrast I am keeping. The alarm drop does not require a black room, though the darker hour moved more of the mood scales.
A 2005 meta of 27 float studies already had a large stress drop in mostly healthy people. Feinstein says the anxious hour moved about twice as far. A later Jonsson sit randomized 50 people with generalized anxiety to 12 sessions or a waitlist and saw a benefit that held at six months. I am staying with the single Tulsa hour.
The reel promised a talk
I paid for a download. The file measured a quieter hour.
Lilly and Shurley started the isolation work in the 1950s at NIMH, and Shurley built a vertical tank with a helmet in 1957 at the Oklahoma City VA. Glenn Perry built the horizontal tank with Lilly in the 1970s so the face could sit above the water. The aisle still sells that room as a portal that talks.
I wanted the talk. The measured sit is the hour that cuts the load. You can want a download and still book the salt.
One person had a panic spike in the first twenty minutes, stayed in the water, and finished the hour with the fear gone on the checklist. Hallucinations were rare and they described colors and shapes, not a voice with a job offer. Fifteen eligible people never showed. Another fifteen rescheduled, often late.
Phone in the locker
Book a shop hour if that is what you have. The Tulsa pool was open and staffed. A closed pod can raise the chest before the salt does any work, so pick a room you can leave, then leave the phone and lie still.
The file has no second n for a notes-app streak or a script you whisper to the dark. The Library keeps the other chairs if you want them later.
Leftover questions about the hour
Does a shop tank count if Tulsa used an open pool?
Feinstein measured an open eight-foot pool with staff on an intercom. A shop pod can still cut load if the salt holds you and the phone stays out. The file does not print a second n for a closed lid.
What if I leave the blue light on?
Twenty-four people kept the light on for most of the hour. The STAI drop stayed large. Serenity and stress moved more in the dark. The alarm drop does not require a black room.
How long did they stay?
The instruction was up to 60 minutes, and forty-eight people stayed the hour. One left at 48 minutes. One left at 22 minutes after salt hit a cut.
What if salt hits a cut?
One person left at 22 minutes because salt stung cuts she had not seen. The sheet already excluded open wounds. Check your skin before you pay.
Is this a medical page?
An open-label hour in a salt pool. Literature. A panic attack that locks a month belongs to a clinician.
The Tulsa pool file
Feinstein J.S., Khalsa S.S., Yeh H-w., Wohlrab C., Simmons W.K., Stein M.B., Paulus M.P. "Examining the short-term anxiolytic and antidepressant effect of Floatation-REST." PLoS ONE 2018;13(2):e0190292. DOI 10.1371/journal.pone.0190292. PMID 29394251 · PMC 5796691 · Received 16 August 2017 · Accepted 4 December 2017 · Published 2 February 2018 · Laureate Institute for Brain Research, Tulsa · Open-label first session of NCT03051074 · n=50 anxious (16 male, 34 female), mean age 36.8 (SD 10.9), education 14.1 (2.2), BMI 29.3 (5.2) · Never floated · Ages 18-55 · ASI-3 recruitment ≥30 and OASIS ≥8, day-of ASI-3 26.6 (14.8), OASIS 9.6 (4.2), PHQ-9 11.4 (6.0), SDS 13.5 (7.8), PSS 25.7 (5.9), happiness 4.4 (2.3), net-time happiness -7.3 (31.2) · GAD n=26, social n=16, panic n=12, agoraphobia n=8, PTSD n=17, unipolar depression n=46 (92%) · SSRI/SNRI n=20, benzodiazepine n=8, none the day of · Severely anxious day-of subgroup n=17 · Open circular pool 8 ft, 11 in water, ~1,800 lb Epsom, specific gravity 1.25-1.26, water 95.0 F (±0.3), air 93.5 F (±0.5) · Up to 60 min · 48/50 full hour, early exits 48 min and 22 min (salt on a cut) · Lights on n=24, dark 2.1 min · Lights off n=26, dark 53.4 min · Duration: 24 wanted longer (48%), 15 perfect (30%), 11 ready (22%) · STAI pre/post t(49)=-15.16, p<.0001, d=2.15 · Serenity d=2.11 · Refreshed d=2.39 · Lights on vs off: STAI d=-2.19 vs -2.15, serenity 1.79 vs 2.51, well-being 0.78 vs 1.39, stress -0.95 vs -1.72, negative affect -0.65 vs -1.05 · All 50 asked to float again · 47 saw therapy potential · 37 (nearly 75%) more relaxation than any prior technique, 82% in the severe subgroup · Reference sample n=30 healthy, 90 min, lights off encouraged, no statistical comparison · van Dierendonck 2005, 27 studies, large stress effect in mostly healthy samples · Jonsson 2016, n=50 GAD, 12 sessions vs waitlist, benefit at 6 months. doi.org/10.1371/journal.pone.0190292 · pubmed.ncbi.nlm.nih.gov/29394251 · pmc.ncbi.nlm.nih.gov/articles/PMC5796691 · NCT03051074