John Lilly pioneered research in dolphin communications and founded the Human Dolphin Foundation in California. He introduced the sophisticated structure and size of the dolphin brain, and created an extensive vocabulary of words in common with the dolphins. Additionally, he assisted in the invention of Samadhi flotation tanks for health and research purposes. Lilly began his tank work in an effort to reduce the pain he experienced from migraine headaches. He claimed that floating in a sensory deprivation tank was the only thing that helped his migraines.