REST - research on dark retreat therapies

Restricted Environmental Stimulation Therapy (REST) is a therapeutic procedure focused on reducing sensory input.
It is often divided into two related methods: Flotation REST, and Chamber REST. First of those two is a brief, usually one hour long stay in a deprivation tank. The tank is filled with a salt water solution, and the water is kept at skin temperature. Also, the tank is dark and soundproof. In turn, chamber REST means a longer, often several days long stay in a comfortable, and entirely darkened environment.
Both methods are related, but each of them has its advantages and limitations. Short duration of flotation REST can be seen as an advantage – making it easier to undergo the therapy session. But it is also a limitation – because only during longer stays it is possible to enter more deeply into the process of regeneration, self-observation, and recovery. It is also easier to integrate new insights and experiences when they develop gradually with time. Chamber REST requires more serious commitment of time – usually from 2 days up to one week. Person doing the retreat can work with processes which require time to arise. With the chamber REST there is no rush – on the contrary - there is plenty of time both for internal experiences, working with body and mind, resting, and integrating what happens during the retreat.
Both flotation and chamber REST have large therapeutic potential, which is attested by growing number of scientific publications. Some of the studies report diminished stress levels, and increased relaxation, which is reflected in lower blood pressure, pulse, and lower levels of stress hormones (cortisol). Published meta-analyses (i.e. research papers which combine results from many studies) show that this stress reduction effect is large and reliable – it can be observed in the majority of published research.
Besides stress reduction there are other documented benefits of REST. Published results show reductions of pain, hypertension, depression, fatigue and burnout. Other research suggest that REST may be effective in the treatment of addictions, anxiety, panic attacks, post-traumatic stress disorder, and anorexia. Undergoing research projects investigate REST in the treatment of sleep disorder and chronic pain.
Apart from various therapeutic effects, research results show increased levels of creativity. And as a last remark – this post was describing research on therapeutic applications of REST. However, dark retreats go far beyond treatment or therapy. This method was created much before our current era of scientific psychology, and originally it was devised as a support for meditation and self-discovery.