In the 1960s, with the development of sophisticated instruments to measure minute changes in the physical functions of laboratory animals, some scientists wondered what would happen to humans who were hooked up to these measuring devices, so that they could observe the activity of their own bodies. The early experiments consisted of measuring subjects’ brain waves, and the scientists discovered that within a few minutes most subjects could exercise control over their supposedly involuntary brain waves and could generate large quantities of alpha waves. As research progressed they found that they could “feed back” a signal monitoring not only brain waves but also galvanic skin response (which measures level of arousal), muscular tension, heart rhythms, the activity of internal organs, the temperature of various specific areas of skin- virtually any physical process that could be measured. More tantalizing, they discovered that whatever physical process could be measured, and fed back, could be brought under control. Researcher, John Basmajian, demonstrated that the control we have over our bodies is so sophisticated we can learn to manipulate a single specific neuron.
All floaters know the feeling of closing the door of the tank, sinking into the black void, and suddenly being able to hear every heartbeat pounding like a pile driver, blood pulsing through veins that cover the body like an exquisite lacework- every physical sensation is magnified, and because there is no possibility of outside distraction, we are able to focus at will upon any part or system of the body. Clearly the floatation tank is, as numerous floaters have discovered, a natural biofeedback machine. The faint body signals that we would ordinarily ignore, or which are drowned out, become powerful presences when we are in the floatation tank. In fact, evidence now indicates that conscious control over physical processes is gained more easily in floatation because intense awareness of internal signals is combined with the extraordinarily deep state of relaxation provided by the tank. Researchers have consistently noted that the most important prerequisite for attaining control over any body function through biofeedback is relaxation. In the tank, deep relaxation and its accompanying intensified awareness of internal states come rapidly, easily, and reliably.