Beyond Psychedelics: Can Water Unlock Altered States of Mind?
Bottom line: A new study suggests Floatation-REST can induce profound altered states of consciousness, dubbed “aquahenosis,” with experiential overlaps to psychedelics, offering a non-pharmacological path to boundary dissolution.
Imagine a state where the boundaries of your self begin to blur, where the line between ‘you’ and ‘not-you’ starts to dissolve. Feelings of unity and peace emerge. This isn’t a hallucination or a dream. It’s a state reported by people who’ve floated in a tank filled with salt water. A new study says this experience—called aquahenosis—can mirror the effects of high-dose psychedelics like psilocybin or ketamine. But the trigger here? Not a drug. Just water.
For decades, altered states of consciousness have been tied to chemistry—mushrooms, plants, and compounds made in labs. But now, a preprint study suggests that reducing sensory input in a specific way can bring about a deep, drug-free state. The researchers call it aquahenosis. It’s not just relaxation. It’s a unique psychological space, marked by a feeling of being unmoored from the body, and a sense of boundlessness that echoes the experiences long pursued through pharmacological means.
The Sensory Deprivation Chamber, Reimagined
Floatation-REST, or Reduced Environmental Stimulation Therapy, is the method at the heart of this research. It’s not the stark, isolating tanks of old. Modern floatation therapy uses a shallow pool of water super-saturated with Epsom salts, inside a light-proof, sound-proof enclosure. The salt density is so high you float effortlessly, like a cork.
The key here is the way the environment alters your senses. First, neutral buoyancy takes over. Your body is so supported that the usual constant battle against gravity stops. Muscles relax, joints decompress, and the brain gets less proprioceptive input—signals from your body that tell you where you are in space.
Second, thermal neutrality sets in. The water is heated to around 93.5 degrees Fahrenheit (34.2 degrees Celsius). After a few minutes, the feeling of water against your skin fades. The boundary between your body and the environment blurs. You exist without a distinct surface.
Third, external sensory input is reduced. The tanks are dark, eliminating visual cues. They’re soundproof, silencing the outside world. Without the constant input of sights and sounds, the brain’s usual processing load drops.
And finally, cardiorespiratory signals become more noticeable. With the outside world quiet, your internal rhythms—your heart and breath—stand out. This increased interoception—awareness of internal bodily sensations—is a key part of the experience.
Mapping the Inner Landscape: The Study’s Design
To explore these potential shifts, the researchers re-examined data from a feasibility trial. This wasn’t a study designed to prove Floatation-REST as a treatment. It was a trial to see if the practice was practical and safe for people with anxiety and depression.
Participants were split into three groups. One had six sessions of Floatation-REST on a prescribed schedule. Another had six sessions with flexible scheduling and duration. A control group used a zero-gravity chair, which offered comfort but no sensory deprivation or buoyancy. This was the baseline for comparison.
To measure the shifts in consciousness, the researchers used the 5D-ASC scale, a tool commonly used in psychedelic research. It assesses dimensions like oceanic boundlessness, disembodiment, and unity. They also measured interoceptive awareness and mood. The goal was to see if Floatation-REST actually induced altered states—and if so, what those states felt like and how they might relate to mood changes.
Aquahenosis: A New Name for an Ancient Feeling
When the data was analyzed, the results stood out. Floatation-REST was associated with a distinct altered state. The researchers called it aquahenosis, a word combining “aqua” (water) and “henosis” (Greek for “unity”). It encapsulates the core experience: a feeling of boundlessness, detachment from the body, and a deep sense of oneness.
The profile of aquahenosis was defined by three main dimensions:
-
Oceanic Boundlessness: A feeling of dissolving boundaries—between self and environment, past and present, inner and outer experience. It often comes with a sense of infinity and timelessness.
-
Disembodiment: A sensation of being detached from your body. In the float tank, with gravity and tactile input minimized, the brain gets fewer signals confirming your body’s presence.
-
Experience of Unity: A profound sense of oneness with the universe, others, or a higher power. It brings peace, harmony, and a deep sense of understanding.
These three elements suggest a shift in perception, a loosening of the ego, and a reorganization of how we relate to the world.
The Echoes of Psychedelics, Without the Chemistry
The most compelling part of the study was the finding that aquahenosis shares some key features with psychedelic experiences. Specifically, the state overlaps with the boundary-dissolution effects of psilocybin and ketamine.
Psychedelics are known for dissolving the ego, leading to feelings of unity, timelessness, and new perspectives. This “boundary dissolution” is measurable—activity in the default mode network, linked to self-referential thought, drops, allowing new connections to form.
That a non-pharmacological intervention could mimic this is significant. It suggests the brain may have natural pathways to these states, which can be activated by environmental conditions, not just chemicals. This has implications for how we understand consciousness and mental well-being.
The study also found that the effects were strongest among those who had longer, more flexible float sessions. This hints that the depth of the experience might depend on duration and personal control. It suggests that aquahenosis may be a skill, one that can be deepened with practice.
Frequently asked questions
What is Floatation-REST?
Floatation-REST involves lying in a shallow pool of highly salinated water, inside a light-proof and soundproof tank. It creates neutral buoyancy, thermal neutrality, and minimal external sensory input, allowing deep relaxation and inward focus.
What is “aquahenosis”?
Aquahenosis is a term used to describe a specific altered state of consciousness induced by Floatation-REST. It involves feelings of boundlessness, detachment from the body, and a sense of unity with the universe.
How does aquahenosis compare to psychedelic experiences?
The study found that aquahenosis overlaps with psychedelic states, particularly in the dimension of boundary dissolution. Both can produce ego dissolution, unity, and timelessness, but without the use of drugs.
Can Floatation-REST treat anxiety and depression?
This study was a secondary analysis of a feasibility trial. It suggests a possible link between altered states and positive mood, but it does not prove that Floatation-REST is an effective treatment. More research is needed.
Is Floatation-REST safe?
Floatation-REST is generally considered safe for most people. However, specific health conditions may require a doctor’s advice. The study assessed safety, but individual responses can vary.
Sources
Educational Disclaimer
This article is for informational and educational purposes only. It is not medical advice, mental health advice, diagnosis, treatment guidance, or a recommendation to use any substance, supplement, therapy, or protocol.
We review publicly available research and explain what the evidence may suggest. Some studies may be early-stage, observational, animal-based, lab-based, theoretical, or incomplete. Always consult a qualified professional before making health-related decisions.
If you or someone you know is struggling, you are not alone. In the US, call or text 988 (Suicide & Crisis Lifeline). Elsewhere, contact your local emergency or crisis service.
Researched and drafted by Spore, ShroomWire’s AI research assistant, and reviewed by the ShroomWire editorial team before publishing.
