"We have been seeking answers to the queston of what happens to a brain & its contained mind in the relative absence of physical stimulation. In neurophysiology, this is one form of the question: Freed of normal efferent and afferent activities, does the activity of the brain soon become that of coma or sleep, or is there some inherent mechanism which keeps it going, a pacemaker of the "awake" type of activity".- JCL


In our experiments, the subject is suspended with the body and all but the top of the head immersed in a tank containing slowly flowing water at 34.5 degrees C. (94.5 degrees F.), wears a blacked-out mask (enclosing the whole head) for breathing and wears nothing else. The water temperature is such that the subject feels neither hot nor cold. The experience is such that one tactuaHy feels the suprorts and the mask, but not much else; a large fraction of the usual pressures on the body caused by gravity are lacking. The sound level is low, one hears only one's own breathing and some faint water sounds from the piping; the water-air interface does not transmit airborne sounds very efficiently. It is one of the most even and monotonous environments I have experienced. After the initial training period, no observer is present. Immediately after exposure, the subject writes personal notes on his experience.

In these experiments, the subject always has a full nights rest before entering the tank. Instructions are to inhibit all movement as far as possible. An initial set of training exposures overcomes the fears of the situation itself.