John C. Lilly's Isolation Tank Valve

Origin
John C. Lilly was a physician and psychoanalyst who performed experiments in psychology, biology and computer science. He invented and promoted the use of an isolation tank as a means of sensory deprivation. Afterwards, he began research into the intelligence of dolphins, whales and similar marine mammals. After his introduction to psychedelic drugs, he combined his previous researches to explore human consciousness, sometimes within an isolation tank or in the presence of dolphins.

Effects
The user develops the ability to communicate with cetacean marine mammals, usually dolphin and whale species. They can create specific tones of clicks and moans and will consciously understand the meaning of any response they garner. All of the user’s other senses besides hearing will be cut off.