The overarching purpose of the current thesis was to assess the long term effects of a treatment program involving flotation-REST for the experience of pain, from the point of view of variables connected with Melzack´s neuromatrix theory, and to examine the extent of a potential attention-placebo effect in connection with flotation-REST.

The first study (Paper I) aimed to investigate long-term effects of flotation-REST four months after treatment. Seventy patients participated, diagnosed as having stress-related pain. Participants were randomly assigned to either a control group or a flotation-REST group and participated in a total of twelve flotation REST or control sessions. Results indicated that pain areas, stress, anxiety and depression decreased, while sleep quality, optimism, and prolactin increased. Positive effects generally maintained four months after treatment. The second (Paper II) examined the potential effects of attention-placebo. Thirty-two patients who were diagnosed as having stress-related muscular pain were treated for a period of six weeks. Half of the patients were also given attention for a period of 12 weeks, while the remainder received attention for 6 weeks. Participants in both groups exhibited lowered blood pressure, reduced pain, anxiety, depression, stress, and negative affectivity, as well as increased optimism, energy, and positive affectivity. The third (Paper III) investigated whether or not 33 flotation sessions were more effective for stress related ailments as compared to 12 sessions. Participants were 37 patients with stress related ailments. Analyzes for subjective pain and psychological variables typically indicated that 12 sessions were enough to get considerably improvements and no further improvements were noticed after 33 sessions. Finally, the fourth study (Paper IV) aimed to examine whether and how the combination of therapy and flotation tank could be used to treat patients with severe stress problems. Two women on long-term sick-leave participated in the study, which was carried out over a period of one year. Four overarching themes were generated: the therapeutic work model, transformation of feelings, self-insight and meaning. These together constituted a “therapeutic circle” which after a while transformed in to a “therapeutic spiral” of increased meaning and enhanced wellbeing.

It was therefore concluded that flotation tank therapy is an effective method for the treatment of stress-related pain.