Here's an interesting article I found, definitely to try experience...
I'm will visit a domina studio in Madrid in mid November and have arranged for a session with 2 dominas, I'm really looking forward to this:
http://www.enspire.com/hypnosis_information_articles/sensory_deprivation/sensory_deprivation.html
"Partial sensory deprivation, including changes in patterns and relationships of sensory input, cause a state of relaxation conductive to an altered state. Awareness of one's surroundings remains and hypnagogic activity is likely to occur. A reduction of external stimuli allows an individual to focus inward due to the absence of attending to a sensory input. Altering sensory perception allows for a focusing of the mind which in time produces an altered state. Relaxation, time to think without distractions, vivid imagery, and feelings of love and warmth are common experiences." [Wallace and Fisher, 1991]
http://hypnagogic.org/
hypnagogic (also hypnogogic)
1.Inducing sleep; soporific
2.Of or relating to the state preceding sleep.
"The sudden de-stimulation of large areas of the nervous system triggers a spontaneous chain reaction throughout the body known as the parasympathetic response. Muscle tension, blood pressure, heart rate and oxygen consumption all drop dramatically. The whole chemistry of the body changes.
Blood vessels including capillaries dilate, improving cardiovascular efficiency and increasing the supply of oxygen and nutrients to every single cell in your body. This is called the vasodilatory effect
Stress related chemicals such as adrenaline, cortisol, ACTH and lactate are removed from the bloodstream and replaced by beneficial endorphins. High levels of cortisol and ACTH are known to weaken the body's immune system and create feelings of depression, while lower baseline levels are associated with feelings of dominance and confidence.
The endorphin - only discovered by NIMH researchers in 1976 - is literally the essence of pleasure. The body's endorphin level is what makes some people naturally happy and others less so. Sometimes called "the body's natural opiate", the endorphins released while floating create intense feelings of well-being, alleviating fatigue and chronic pain, as well as improving many of the higher brain functions such as memory and learning. Happiness is not an illusion - it is an endorphin.
These biochemical changes occur naturally and spontaneously as by-products of deep sensory relaxation. No training or techniques are required. Just lie back and let it happen.
Take care and enjoy,
Happy