Induction of altered states of consciousness during Floatation-REST is associated with the dissolution of body boundaries and the distortion of subjective time.

Floatation-REST, which minimizes sensory input by having people float in warm, salt-saturated water in a dark, silent tank, produces stronger altered states of consciousness—specifically a dissolving sense of body boundaries and distorted time perception—than simply lying on a waterbed in a dark, quiet room. In a crossover trial with 50 healthy adults, a 60-minute float session led to greater relaxation, less anxiety, and less tiredness compared to the control condition. The loss of body boundaries during floating directly contributed to the reduction in anxiety, pointing to a previously unknown mechanism behind floatation's calming effects.

Study at a glance

Abstract

Floatation-REST (Reduced Environmental Stimulation Therapy) minimizes stimulation of the nervous system by immersing subjects in an environment without sound or light while they effortlessly float in thermoneutral water supersaturated with Epsom salt. Here we investigated the relationship between altered states of consciousness (ASC) and its association with the affective changes induced by Floatation-REST. Using a within-subject crossover design, 50 healthy subjects were randomized to 60 min of Floatation-REST or 60 min of Bed-REST (an active control condition that entailed lying supine on a warm waterbed in a dark and quiet room). Following Floatation-REST, subjects felt significantly more relaxed, less anxious, and less tired than after Bed-REST. Floatation-REST also induced significantly more pronounced ASC characterized by the dissolution of body boundaries and the distortion of subjective time. The loss of body boundaries mediated the loss of anxiety, revealing a novel mechanism by which Floatation-REST exerts its anxiolytic effect.